People often forget that many voltage regulator ICs have an upper limit (usually 35 V) on the input voltage they can handle. That applies primarily to types with a fixed output voltage. Adju... Read more
There are only a limited number of switching regulators designed to generate neg-ative output voltages. In many cases, it’s thus necessary to use a switching regulator that was actually desi... Read more
This circuit was developed to power an AVR microcontroller from a 12 V leadacid battery. The regulator itself draws only 14 μA. Of course, there are dedicated ICs, for example from Linear Te... Read more
This small but very effective circuit protects a lead-acid battery (12-V solar battery or car battery) against overcharging by a solar module when the incident light is too bright or lasts t... Read more
Standard three-legged voltage regulator chips like the LM317 can cope with an input voltage of up to about 30 V, a few high-voltage types can handle 60 V but if that is still not sufficient... Read more
This circuit shows that dimmers intended for use at mains voltage do not always have to contain a triac. Here, a MOSFET (BUZ41A, 500 V/4.5A) in a diode bridge is used to control the voltage... Read more
In many small battery powered apparatus it is common to have an LED act as a combined indicator for ‘power-on’ and ‘battery state’. The most commonly seen circuit for this is shown in Figure... Read more
Display driver ICs are available in several standard implementations. This circuit makes use of a GAL 22V10 to drive two 7-segment displays without multiplexing. A 4-bit binary code at input... Read more
The use of solar photovoltaic (PV) energy sources is increasing due to global warming concerns on the one hand, and cost-effectiveness on the other. Many engineers involved in power electron... Read more
Some microcontroller applications require status information or other important data to be stored to EEPROM immediately as a power to the equipment is turned off or fails. When power is resu... Read more
