Monthly Archives: February 2010

High-Brightness LED-Driver

Posted on February 26, 2010 by Elia
High-Brightness LED-Driver

This is a high-brightness LED-driver circuit. To provide a constant-voltage output we usually use DC/DC regulators. But constant-current output is the one that is needed in LED application. To provide a constant-current output, we can use this circuit. Here is … Continue reading →

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Step-Down Charge Pump Regulator for USB Powered Devices

Posted on February 26, 2010 by Rust
Step-Down Charge Pump Regulator for USB Powered Devices

this is a circuit of Step-Down Charge Pump Regulator for USB Powered Devices. The critical design parameter of this circuit is the circuit area. To solve this problem we can use Charge pump step-down circuit. This circuit only requires   the … Continue reading →

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PWM Modulator Using Op-Amp

Posted on February 26, 2010 by Rust
PWM-Modulator-Using-Op-Amp

This is a simple PWM modulator circuit. Comparing the message signal to a ramp or triangular waveform is the simplest way to produce a PWM signal. When the input is greater than the triangular waveform (the carrier), the resulting output … Continue reading →

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