Circuits & Schematics Supply - 5

When parts have been around as long, and in such widespread use, as the venerable LM317 and LM337 (and their siblings), you tend to think every trick that can be played with them is already in the (data)book. So, when the question arose whether ...

Whether you use them as indicators or to provide illumination, LEDs are hard to beat in efficiency, reliability, and cost. White LEDs are rapidly gaining popularity as sources of illumination, as in LCD backlights, but with forward voltages ...

The circuit in Figure 1 is similar in principle to that of a previous Design Idea ( Reference 1 ) but offers improved, more reproducible performance. The output current is almost constant over an input-voltage range of 1.2 to 1.5 V and is ...

LED drivers have lots of features and require plenty of external components. When your application requires no PWM (pulse-width-modulated) dimming or controlled frequency operation, your primary concern may be that too much current could damage or ...

The schematic in Figure 1 shows a way to increase the power available from a current-limited 5 V supply by adding power from a 5 V supply. The dc/dc converter generates a single 12 V, 150-mA (1.8 W) output from two regulated and current-limited ...

Introduction High voltage buck DC/DC controllers such as the LTC3890 (dual output) and LTC3891 (single output) are popular in automotive applications due to their extremely wide 4 V to 60 V input voltage range, eliminating the need for a snubber ...

The circuit in this Design Idea uses an intrinsic property of collector voltages in one-transformer pushpull dc/dc converters: They have a swing of twice the supply voltage. When you implement these circuits with an NPN device, the collector swings ...

This article describes an active load circuit that can be used to simulate a battery in any state of charge. The battery simulator provides a constant-voltage load for a battery-charging circuit, independent of applied charging current. The ...

It is often desirable to determine a battery’s internal resistance to evaluate its condition or suitability for an application. Accurate battery resistance determination is complicated by inherent capacitive terms which corrupt results taken ...

Some circuits need a constant-current source that does not necessarily connect to a power-supply rail or to ground. The circuit in the Figure 1 shows a simple method for achieving that configuration. Figure 1. The simple method achieves a ...