This article describes how to assemble a simple but effective LED brightness control based on PWM dimming () LED lighting.

LEDs (light emitting diodes) are very sensitive components. When the supply current or voltage exceeds allowable value may lead to their failure or significantly reduce the service life.

Usually, the current is limited using a resistor connected in series with the LED, or by a circuit current regulator (). Increasing the current on the LED increases its intensity, and reducing the current reduces it. One way to control the brightness of the glow is to use a variable resistor () to dynamically change the brightness.

But this is only applicable to a single LED, since even in the same batch there may be diodes with different luminous intensity and this will affect the uneven luminescence of a group of LEDs.

Pulse width modulation. A much more efficient method of regulating the brightness of the glow by applying (PWM). With PWM, the groups of LEDs are supplied with the recommended current, while at the same time being able to dim the brightness by supplying power at a high frequency. Changing the period causes a change in brightness.

The duty cycle can be thought of as the ratio of the power on and off times supplied to the LED. For example, if we consider a cycle of one second and at the same time the LED will be 0.1 seconds off, and 0.9 seconds on, it turns out that the glow will be about 90% of the nominal value.

Description of PWM dimmer

The easiest way to achieve this high frequency switching is to use a IC, one of the most common and most versatile ICs ever made. The PWM controller circuit shown below is intended to be used as a dimmer to power LEDs (12 volts) or as a speed controller for a motor. direct current at 12 V.

In this circuit, the resistors to the LEDs need to be adjusted to provide a forward current of 25mA. As a result, the total current of the three lines of LEDs will be 75mA. The transistor must be rated for a current of at least 75 mA, but it is better to take it with a margin.

This dimmer circuit is dimmable from 5% to 95%, but by using germanium diodes instead of , the range can be extended from 1% to 99% of the nominal value.

LEDs are becoming more and more part of our daily lives. We change incandescent lamps in an apartment or house, halogen in a car to LED. In order to adjust the brightness of an Addison bulb, a dimmer is usually used - this is such a thing with which you can limit the alternating current, thereby changing the brightness of the glow to the one you need, why pay more, and even feel discomfort due to excessively bright light? The power regulator can generally be used for many consumers (soldering iron, grinder, vacuum cleaner, drill ...) from AC voltage networks, they are built, as a rule, on the basis of a triac.

The LEDs are powered by a constant and stabilized current, so it will not be possible to use a standard dimmer here. If you just change the voltage applied to it, then the brightness will change very sharply, current is important for them, but instead of a current regulator, we will do something else, namely PWM (Wide Pulse Modulator), it will turn off the power supply from the LED for a certain time, the brightness will decrease, but we will not notice the blinking, since the frequency is such that the human eye will not notice this. Microcontrollers are not used here, because their presence can become an obstacle to assembling the device, you need to have a programmer, a certain software... Therefore, this simple circuit uses only simple and public radio components.

It is possible to use such a thing for any inertial loads, that is, those that can store energy, because, for example, if you disconnect the DC motor from the power source, then it will not stop rotating immediately.

The circuit, in my opinion, can be conditionally divided into two parts, namely, this is a generator made on the mega-popular timer NE555 (analogue -KR1006VI1) and a powerful opening / closing transistor, with which power is supplied to the load (here 555 operates in the mode astable multivibrator). We use a powerful NPN bipolar transistor (I took TIP122), but it is possible to replace it with a field-effect (MOSFET) transistor. The pulse generator frequency, period, pulse duration is set by two resistors (R3, R2) and capacitors (C1, C2), and we can change it with a resistor with resistance adjustment.

Schematic Components

There are a lot of programs for calculating the analog 555 timer, you can experiment with the values ​​\u200b\u200bof the components that affect the frequency of the generator - this is all easily miscalculated using many programs such as this one. Denominations can be changed a little, everything will work and so. Pulse diodes 4148 are easily replaced by domestic KD222. Capacitors 0.1 uF and 0.01 uF disc ceramic. variable resistor set the frequency, for a good and smooth adjustment, its maximum resistance is 50 kOhm.

Everything is assembled on discrete elements, the board has dimensions of 50-25 mm.

How does the circuit work?

The device works as a switch between two modes: current is supplied to the load and current is not supplied to the load. The switching happens so quickly that our eyes do not see this blinking. So, this device regulates power by changing the interval between the time when power is on and when it is turned off. I think you understand the essence of PWM. This is what it looks like on the oscilloscope screen.

The first picture shows a faint glow, because during the period T the pulse length t1 takes only 20% (this is the so-called duty cycle), and the rest 80% we have a logical 0 (no voltage).

The second picture shows us a signal called a meander, then we have t1=0.5*T, that is, the duty cycle and Coef. Fills are 50%.

In the third case we have D=90%. The LED shines almost at full brightness.

Imagine that T=1 second, then in the first case

§ 1) within 0.2s, current will flow to the LED, but not 0.8s

§ 2)0.5s current applied 0.5s no

By the way, having made three PWM controllers according to the scheme and connecting them to one RGB tape, it becomes possible to set the desired gamut of the glow. Each of the boards controls its own LEDs (red, green and blue) and by mixing them in a certain sequence you achieve the desired glow.

What is the energy loss of this device?

Firstly, these are a measly few milliamps that consume a pulse generator on a microcircuit, and then there is a power transistor, on which power is dissipated approximately equal to P=0.6V*I consumptionload . The base resistor can be neglected. In general, PWM losses are minimal because the pulse width control system is very effective, since very little energy is wasted (and, therefore, little heat is released).

Outcome

As a result, we got a beautiful and simple PWM. It turned out to be very convenient for them to adjust the pleasant power of the glow for themselves. Such a device will always come in handy in everyday life.

  • Next >

If you miss the details and explanations, then the LED brightness control circuit will appear in the very simple form. This control is different from the PWM method, which we will discuss a little later.
So, the elementary regulator will include only four elements:

  • power unit;
  • stabilizer;
  • variable resistor;
  • light bulb directly.

Both the resistor and the stabilizer can be bought at any radio shop. They are connected exactly as shown in the diagram. The differences may lie in the individual parameters of each element and in the way the stabilizer and resistor are connected (by wire or by soldering directly).

Having assembled such a circuit with your own hands in a few minutes, you can make sure that by changing the resistance, that is, by turning the resistor knob, you will adjust the brightness of the lamp.

In an illustrative example, the battery is taken at 12 volts, the resistor is 1 kOhm, and the stabilizer is used on the most common Lm317 chip. The scheme is good because it helps us take the first steps in radio electronics. This is an analog way to control brightness. However, it is not suitable for devices that require finer adjustments.

The need for dimmers

Now let's take a closer look at the issue, find out why brightness control is needed, and how you can control the brightness of the LEDs in a different way.

  • The most famous case where a dimmer switch for multiple LEDs is needed is in residential lighting. We are used to controlling the brightness of light: making it softer in the evening, turning it on at full power during work, highlighting individual objects and parts of the room.
  • Adjusting the brightness is also necessary in more complex devices, such as TV and laptop monitors. Car headlights and flashlights are indispensable without it.
  • Adjusting the brightness allows us to save electricity when it comes to powerful consumers.
  • Knowing the adjustment rules, you can create an automatic or remote control light, which is very convenient.

In some devices, simply reducing the current value by increasing the resistance is not possible, as this can lead to a change in white to greenish. In addition, an increase in resistance leads to an undesirable increased heat generation.

The way out of a seemingly difficult situation was PWM control (pulse width modulation). Current is supplied to the LED in pulses. Moreover, its value is either zero or nominal - the most optimal for glow. It turns out that the LED periodically lights up, then goes out. The longer the glow time, the brighter, as it seems to us, the lamp shines. The shorter the glow time, the dimmer the bulb shines. This is the principle of PWM.

You can control bright LEDs and LED strips directly using high-power MOSFETs or, as they are also called, MOSFETs. If you want to control one or two low-power LED bulbs, then ordinary bipolar transistors are used as keys or LEDs are connected directly to the outputs of the microcircuit.

By turning the R2 rheostat knob, we will adjust the brightness of the LEDs. Here are the LED strips (3 pcs.), Which are connected to one power source.

Knowing the theory, you can assemble a PWM device circuit on your own, without resorting to ready-made stabilizers and dimmers. For example, such as is offered on the Internet.

NE555 is a pulse generator in which all timing characteristics are stable. IRFZ44N - the one powerful transistor capable of driving high power load. The capacitors set the frequency of the pulses, and the load is connected to the "output" terminals.

Since the LED has low inertia, that is, it lights up and goes out very quickly, the PWM control method is optimal for it.

Ready-to-use dimmers

The regulator, which is sold ready-made for LED lamps are called a dimmer. The frequency of the pulses, creating them, is large enough so that we do not feel flicker. Thanks to the PWM controller, a smooth adjustment is carried out, allowing you to achieve maximum brightness of the glow or the extinction of the lamp.

By embedding such a dimmer in the wall, you can use it like a conventional switch. For exceptional convenience, the LED dimmer can be controlled by a radio remote control.

The ability of lamps based on LEDs to change their brightness opens up great opportunities for conducting light shows and creating beautiful street lighting. Yes, and an ordinary flashlight becomes much more convenient to use if it is possible to adjust the intensity of its glow.

LEDs are used in almost every technology around us. True, sometimes it becomes necessary to adjust their brightness (for example, in flashlights, or monitors). by the most easy way out in this situation, it seems to change the amount of current passed through the LED. But it's not. The LED is a rather sensitive component. Permanent change the amount of current can significantly reduce its life, or even break it. It should also be borne in mind that a limiting resistor cannot be used, since excess energy will accumulate in it. This is not allowed when using batteries. Another problem with this approach is that the color of the light will change.

There are two options:

  • PWM regulation
  • analog

These methods control the current flowing through the LED, but there are certain differences between them.
Analog regulation changes the level of current that passes through the LEDs. And PWM regulates the frequency of the current supply.

PWM regulation

The way out of this situation can be the use of pulse-width modulation (PWM). With this system, the LEDs receive the required current, and the brightness is regulated by applying power at a high frequency. That is, the frequency of the feed period changes the brightness of the LEDs.
The undoubted plus of the PWM system is the preservation of the productivity of the LED. The efficiency will be about 90%.

Types of PWM regulation

  • Two-wire. Often used in the lighting system of cars. The converter power supply must have a circuit that generates a PWM signal at the DC output.
  • shunt device. To make the on/off period of the converter use a shunt component that provides a path for the output current besides the LED.

Pulse parameters for PWM

The pulse repetition rate does not change, so there are no requirements for determining the brightness of light. In this case, only the width, or time, of the positive pulse changes.

Pulse frequency

Even taking into account the fact that there are no special claims to the frequency, there are boundary indicators. They are determined by the sensitivity of the human eye to flickering. For example, if in a movie the flickering of frames must be 24 frames per second, so that our eye perceives it as one moving image.
In order for the flickering of light to be perceived as uniform light, the frequency must be at least 200 Hz. There are no restrictions on the upper indicators, but there is no way below.

How a PWM controller works

To directly control the LEDs, a transistor key stage is used. Usually they use transistors that can store large amounts of power.
This is required when using LED strips or powerful LEDs.
For a small amount or low power, the use of bipolar transistors is quite sufficient. You can also connect LEDs directly to the chips.

PWM generators

In a PWM system, a microcontroller or a circuit consisting of circuits of a small degree of integration can be used as a master oscillator.
It is also possible to create a regulator from microcircuits that are designed for switching power supplies, or K561 logic microcircuits, or an NE565 integrated timer.
Craftsmen even use an operational amplifier for this purpose. For this, a generator is assembled on it, which can be adjusted.
One of the most used circuits is based on the 555 timer. In fact, this is a regular generator rectangular pulses. The frequency is controlled by capacitor C1. at the output of the capacitor should be high voltage(this is the same with the connection to the positive power supply). And it charges when there is a low voltage at the output. This moment gives rise to pulses of different widths.
Another popular circuit is PWM based on the UC3843 chip. in this case, the switching circuit has been changed towards simplification. In order to control the pulse width, a control voltage of positive polarity is used. In this case, the desired PWM pulse signal is obtained at the output.
The control voltage acts on the output in the following way: with a decrease, the latitude increases.

Why PWM?

  • The main advantage of this system is ease. The usage patterns are very simple and easy to implement.
  • The PWM control system gives a very wide range of brightness control. If we talk about monitors, then it is possible to use CCFL backlighting, but in this case, the brightness can only be reduced by half, since CCFL backlighting is very demanding on the amount of current and voltage.
  • Using PWM, you can keep the current at a constant level, which means the LEDs will not suffer and the color temperature will not change.

Disadvantages of using PWM

  • Over time, image flicker can be quite noticeable, especially at low brightness or eye movement.
  • If the light is constantly bright (such as sunlight), the image may become blurry.

Chip NCP1014 is a PWM controller with a fixed conversion frequency and a built-in high-voltage switch. Additional internal blocks implemented as part of the microcircuit (see Fig. 1) allow it to meet the entire range of functional requirements for modern power supplies.

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Series controllers NCP101X were discussed in detail in an article by Konstantin Staroverov in issue 3 of the journal for 2010, therefore, in the article we will limit ourselves to considering only key features microcircuits NCP1014, and we will focus on the consideration of the calculation features and the mechanism of operation of the IP, presented in the reference design.

Features of the NCP1014 controller

  • Integrated output 700V low resistance MOSFET open channel(11ohm);
  • providing driver output current up to 450mA;
  • the ability to work at several fixed conversion frequencies - 65 and 100 kHz;
  • the conversion frequency varies within ± 3 ... 6% relative to its preset value, which allows you to "blur" the power of radiated interference within a certain frequency range and thereby reduce the EMI level;
  • the built-in high-voltage power supply system is able to ensure the operability of the microcircuit without the use of a transformer with a third auxiliary winding, which greatly simplifies the winding of the transformer. This feature is designated by the manufacturer as DSS ( Dynamic Self-Supply- autonomous dynamic power), however, its use limits the output power of the IP;
  • the ability to work with maximum efficiency at low load currents due to the PWM pulse skipping mode, which makes it possible to achieve low no-load power - no more than 100 mW when the microcircuit is powered from the third auxiliary winding of the transformer;
  • the transition to the pulse skipping mode occurs when the load current consumption drops to a value of 0.25 from the nominal value, which eliminates the problem of generating acoustic noise even when using inexpensive pulse transformers;
  • implemented soft start function (1ms);
  • conclusion feedback voltage is directly connected to the output of the optocoupler;
  • a short circuit protection system with subsequent return to normal operation after its elimination has been implemented. The function allows you to track both directly a short circuit in the load, and the situation with an open feedback circuit in case of damage to the decoupling optocoupler;
  • built-in overheating protection mechanism.

The NCP1014 controller is available in three package types - SOT-223, PDIP-7 and PDIP-7 GULLWING (see Figure 2) with the pinout shown in Figure 2. 3. The latest package is a special version of the PDIP-7 package with special pin molding, making it suitable for surface mounting.

Rice. 2.

Rice. 3.

Typical application diagram of NCP1014 controller in flyback ( flyback) converter is shown in Figure 4.

Rice. four.

IP calculation method based on NCP1014 controller

Consider the method of step-by-step calculation of a flyback converter based on NCP1014 using the example of a reference development of a power supply unit with an output power of up to 5 W to power a system of three series-connected LEDs. One-watt white LEDs with a normalization current of 350 mA and a voltage drop of 3.9 V were considered as LEDs.

first step is to determine the input, output and power characteristics of the developed IP:

  • input voltage range - Vac(min) = 85V, Vac(max) = 265V;
  • output parameters - Vout = 3x3.9V ≈ 11.75V, Iout = 350mA;
  • output power - Pout \u003d VoutxIout \u003d 11.75 Vx0.35 A ≈ 4.1 W
  • input power - Pin = Pout / h, where h is the estimated efficiency = 78%

Pin=4.1W/0.78=5.25W

  • DC input voltage range

Vdc(min) = Vdc(min) x 1.41 = 85 x 1.41 = 120V (dc)

Vdc(max) = Vdc(max) x 1.41 = 265 x 1.41 = 375V (dc)

  • average input current - Iin(avg) = Pin / Vdc(min) ≈ 5.25/120 ≈ 44mA
  • peak input current - Ipeak = 5xIin (avg) ≈ 220mA.

The first input link is a fuse and an EMI filter, and their selection is second step when designing IP. The fuse must be selected based on the value of the breaking current, and in the presented design, a fuse with a breaking current of 2 A is chosen. We will not delve into the procedure for calculating the input filter, but only note that the degree of suppression of common mode and differential noise is highly dependent on the topology printed circuit board, as well as the proximity of the filter to the power connector.

third step is the calculation of parameters and selection of the diode bridge. The key parameters here are:

  • permissible reverse (blocking) diode voltage - VR ≥ Vdc (max) = 375V;
  • forward current of the diode - IF ≥ 1.5xIin (avg) = 1.5x0.044 = 66mA;
  • allowable overload current ( surge current), which can reach five times the average current:

IFSM ≥ 5 x IF = 5 x 0.066 = 330 mA.

fourth step is the calculation of the parameters of the input capacitor installed at the output of the diode bridge. The size of the input capacitor is determined by the peak value of the rectified input voltage and the specified level of input ripple. Larger input capacitor provides more low values ripples, but increases the starting current of the IP. In general, the capacitance of a capacitor is determined by the following formula:

Cin = Pin/, where

fac - network frequency alternating current(60 Hz for the design in question);

DV- allowable level ripples (20% of Vdc(min) in our case).

Cin \u003d 5.25 / \u003d 17 uF.

In our case, we choose a 33uF aluminum electrolytic capacitor.

Fifth and main step is the calculation of the winding product - a pulse transformer. The calculation of the transformer is the most complex, important and "thin" part of the entire calculation of the power supply. The main functions of a transformer in a flyback converter are the accumulation of energy when the control key is closed and the current flows through its primary winding, and then its transfer to the secondary winding when the power to the primary part of the circuit is turned off.

Taking into account the input and output characteristics of the MT, calculated at the first step, as well as the requirements for ensuring the operation of the MT in the continuous current mode of the transformer, the maximum value of the duty cycle ( duty cycle) is equal to 48%. We will carry out all calculations of the transformer based on this value of the fill factor. Let us summarize the calculated and specified values ​​of the key parameters:

  • controller operating frequency fop = 100 kHz
  • fill factor dmax= 48%
  • minimum input voltage Vin(min) = Vdc(min) - 20% = 96V
  • output power Pout= 4.1W
  • estimated value of efficiency h = 78%
  • peak input current Ipeak= 220mA

Now we can calculate the inductance primary winding transformer:

Lpri = Vin(min) x dmax/(Ipeak x fop) = 2.09 mH

The ratio of the number of turns of the windings is determined by the equation:

Npri / Nsec \u003d Vdc (min) x dmax / (Vout + V F x (1 - dmax)) ≈ 7

It remains for us to check the ability of the transformer to “pump” the required output power through itself. You can do this with the following equation:

Pin(core) = Lpri x I 2 peak x fop/2 ≥ Pout

Pin(core) = 2.09 mH x 0.22 2 x 100 kHz/2 = 5.05 W ≥ 4.1 W.

It follows from the results that our transformer can pump the required power.

It can be seen that here we have given a far from complete calculation of the parameters of the transformer, but only determined its inductive characteristics and showed the sufficient power of the chosen solution. Many works have been written on the calculation of transformers, and the reader can find the calculation methods of interest to him, for example, in or. The coverage of these techniques is beyond the scope of this article.

The electrical circuit of the IP, corresponding to the calculations performed, is shown in Figure 5.

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Now it's time to get acquainted with the features of the above solution, the calculation of which was not given above, but which have great importance for the functioning of our IP and understanding the implementation features of the protective mechanisms implemented by the NCP1014 controller.

Features of the operation of the scheme that implements IP

The secondary part of the circuit consists of two main blocks - a block for transferring current to the load and a power supply for the feedback circuit.

When the control key is closed (direct mode), the feedback circuit power supply operates, implemented on diode D6, current-setting resistor R3, capacitor C5 and zener diode D7, which, together with diode D8, sets the required supply voltage (5.1 V) of optocoupler and shunt regulator IC3 .

During the reverse run, the energy stored in the transformer is transferred to the load through diode D10. At the same time, the storage capacitor C6 is charged, which smoothes the output ripples and provides a constant supply voltage to the load. The load current is set by resistor R6 and controlled by shunt regulator IC3.

IP has protection against load disconnection and load short circuit. Short circuit protection is provided by the TLV431 shunt regulator, the main role of which is the OS circuit regulator. A short circuit occurs under the condition of a short breakdown of all load LEDs (in the event of failure of one or two LEDs, their functions are taken over by parallel zener diodes D11 ... D13). The value of the resistor R6 is selected so that at the operating load current (350 mA in our case) the voltage drop across it is less than 1.25 V. controller NCP1014 reduce the output voltage.

The load shutdown protection mechanism is based on the inclusion of a Zener diode D9 in parallel with the load. Under conditions of opening of the load circuit and, as a result, an increase in the output voltage of the IP to 47 V, the zener diode D9 opens. This turns on the optocoupler and forces the controller to reduce the output voltage.

Interested in getting to know NCP1014 in person? - No problem!

For those who, before starting to develop their own IP based on NCP1014, want to make sure that this is a really simple, reliable and effective solution, ONSemiconductor produces several types of evaluation boards (see Table 1, Fig. 6; available for order through COMPEL) .

Table 1. Overview of evaluation boards

Order code Name Short description
NCP1014LEDGTGEVB 8W LED driver with 0.8 power factor The board is designed to demonstrate the possibility of building an LED driver with a power factor > 0.7 (Energy Star standard) without using an additional PFC chip. The output power (8 W) makes this solution ideal for powering structures like the Cree XLAMP MC-E containing four LEDs in series in one package.
NCP1014STBUCKGEVB Non-inverting buck converter The board is proof of the claim that the NCP1014 controller is enough to build a low price range power supply for harsh environments.

Rice. 6.

In addition, there are several more examples of the finished design of various IPs, in addition to those discussed in the article. This and a 5W AC/DC adapter for cell phones, and another IP option for LED, as well as a large number of articles on the use of the NCP1014 controller, which you can find on the official website of ONSemiconductor - http://www.onsemi.com/.

COMPEL is the official distributor of ONSemiconductor and therefore on our website you can always find information on the availability and cost of chips manufactured by ONS, as well as order prototypes, including the NCP1014.

Conclusion

The use of the NCP1014 controller manufactured by ONS makes it possible to develop high-performance AC/DC converters for supplying loads with a stabilized current. Proper use of the key features of the controller allows you to ensure the safety of the final power supply in the conditions of opening or short circuiting of the load with a minimum number of additional electronic components.

Literature

1. Konstantin Staroverov "The use of NCP101X / 102X controllers in the development of medium-power network power supplies", Electronics News magazine, No. 3, 2010, ss. 7-10.

4. Mac Raymond. Switching power supplies. Theoretical foundations of design and guidance on practical application / Per. from English. Pryanichnikova S.V., M.: Dodeka-XXI Publishing House, 2008, - 272 p.: ill.

5. Vdovin S.S. Design of pulse transformers, L .: Energoatomizdat, 1991, - 208 p.: ill.

6. TND329-D. "5W Cellular Phone CCCV AC-DC Adepter"/ http://www.onsemi.com/pub_link/Collateral/TND329-D.PDF.

7. TND371-D. "Offline LED Driver Intended for ENERGY STAR"/ http://www.onsemi.com/pub_link/Collateral/TND371-D.PDF.

Receipt technical information, sample order, delivery - e-mail:

NCP4589 - LDO Regulator
with automatic energy saving

NCP4589 - new 300mA CMOS LDO regulator from ON Semiconductor. The NCP4589 switches to low current mode at low current load and automatically switches back to "fast" mode as soon as the output load exceeds 3 mA.

NCP4589 can be put into permanent mode fast work by forced mode selection (control by special input).

Key Features of NCP4589:

  • Operating range of input voltages: 1.4 ... 5.25V
  • Output voltage range: 0.8…4.0V (in 0.1V increments)
  • Input current in three modes:

      • Low Power Mode - 1.0µA at V OUT< 1,85 В

      Fast Mode - 55µA

      Power saving mode - 0.1 uA

  • Minimum voltage drop: 230mV at I OUT = 300mA, V OUT = 2.8V
  • High voltage ripple rejection: 70dB at 1kHz (in fast mode).

NCP4620 Wide Range LDO Regulator

NCP4620 - This is a CMOS LDO regulator for 150mA from ON Semiconductor with an input voltage range of 2.6 to 10 V. The device has a high output accuracy - about 1% - with a low temperature coefficient of ±80 ppm/°C.

The NCP4620 has overheat protection and an Enable input, and is available with a standard output and an Auto Discharge output.

Key Features of NCP4620:

  • Operating input voltage range from 2.6 to 10V (max. 12V)
  • Output fixed voltage range from 1.2 to 6.0V (100mV steps)
  • Direct minimum voltage drop - 165mV (at 100mA)
  • Power supply ripple suppression - 70dB
  • Chip power off when overheated up to 165°C