Circuits & Schematics

Most electronic clocks, be they analog or digital, use a crystal oscillator (XO) based on a 32.768 kHz crystal for their reference. In fact, it is same crystal that’s commonly used as a real-time clock for many microcontroller systems. These ...

Simple linear and switching voltage regulators with feedback networks of the type shown in Figure 1 are legion. Their output voltages are the reference voltage at the feedback (FB) pin multiplied by 1 + R F /R G . Recommended values of C F from 100 ...

Many applications use FPGAs, ASICs, or DSP chips, which usually require multiple voltage rails, typically two: the core voltage and the I/O voltage. The core voltage is usually lower than the I/O voltage. Guidelines for determining how to power up ...

A simple module to keep power banks from turning off, when your DIY circuit draws low currents. A simple power bank keep alive module. As the name is already suggesting, this module keeps power banks from auto turn off, when the load current is too ...

A while back, I published the Design Idea (DI) “Simple PWM interface can program regulators for V OUT V SENSE ” ( Ref. 1 )It showed some simple circuits for PWM programming of standard bucking-type regulator chips, both linear and ...

Many recent Design Ideas ( Ref, 1 ) have involved button-pushing to control power. Some may have been more resistant to contact-bounce than others but how can we really check that? This DI describes how some simple circuitry can simulate bouncy ...

Precision-matched capacitor pairs are commercially available items, but only in a limited range of values, working voltage, and dielectrics. Plus, sometimes an extra critical application with extra tight tolerances (or an extra tight budget) can ...

Applications such as turbidity measurement and densitometry require cleanly pulsed light sources with stable amplitudes. The LED driver in Figure 1 illuminates retinal neurons in a biological experiment that has similar requirements. For a given ...

I recently published a simple design ( Ref. 1 ) for a platinum resistance detector (PRTD) 4 to 20 mA transmitter circuit, illustrated in Figure 1. Figure 1. The PRTD 4 to 20 mA loop transmitter with constant current PRTD excitation that relies on ...

High accuracy, stability, and wide operating range make platinum RTDs (resistance temperature detectors) popular temperature transducers. Signal conditioning these devices requires care to utilize their desirable characteristics. Figure 1’s ...