The circuit below will trickle charge a four cell pack of AA or AAA NiMH batteries. The circuit draws current from the +5 v available a USB connection and pumps about 70 mA of current into the battery. This should be enough current to fully charge ...
I designed and built this thing many years ago. I published the hobby circuit in the now defunct “Radio Elecronics” magazine back in 1992. The electronic circuit injects a precise 1 Amp of current into any unknown resistor, up to about ...
An inverter provides power backup for mains-based appliances in the event of a power failure. Most of the inverters available in the market have complicated circuit designs and are not very economical. Some of them produce a square-wave output, ...
Recently (5/21/25), I published a Design Idea (DI) describing a bidirectional current mirror using just two transistors and a diode, “A two-way mirror current mirror that is” ( Ref. 1 ). That circuit works well in some applications, ...
Designing an analog circuit can be a frustrating experience, as noted by Nick Cornford in his Design Idea (DI), “DIY RTD for a DMM” ( Ref. 1 ). With a fortnight’s struggle, I completed the design of 4 mA to 20 mA, two-wire ...
At its invention roughly four decades ago, STM (scanning tunneling microscopy) created a sensation because it was the first technology to make atomic-scale-resolution imaging a routine procedure. An essential requirement for the practical ...
The typical regulator output network Many voltage regulator chips, both linear and switching, use the same basic two-resistor network for output voltage programming. Figure 1 illustrates this feature in a typical switching (buck type) regulator, ...
3.8-V to 30-V, 3-A, 200-kHz to 2.2-MHz, low-IQ synchronous buck converter in SOT-583 package The TPS6293x is a high-efficiency, easy-to-use synchronous buck converter with a wide input voltage range of 3.8 V to 30 V, and supports up to 2-A ...
3.8-V to 30-V, 3-A, 200-kHz to 2.2-MHz, low-IQ synchronous buck converter in SOT-583 package The TPS6293x is a high-efficiency, easy-to-use synchronous buck converter with a wide input voltage range of 3.8 V to 30 V, and supports up to 2-A ...
Semiconductor laser diodes (SLDs) are often packaged with a photodiode. The output current from this photodiode can be monitored to regulate the output power intensity of the laser diode. SLDs, however, are prone to pathological drifts, such as ...