Limit Inrush Current In High-Power Applications - 02/03/11 EDN Design Idea Protect circuits from high current until a capacitor charges.
A high-power offline supply is nothing more than a half- or full-bridge dc/dc converter. Rectifying the
ac line yields a dc voltage that feeds the converter. At power-supply turn-on, the bulk capacitor of the
uncontrolled rectifier is completely discharged. It results in a huge charging current for a high
instantaneous line voltage because the discharged bulk capacitor temporarily short-circuits the diodes of
the rectifier stage.
[by JB Castro-Miguens, Cesinel, Madrid, Spain, and C Castro-Miguens, University of
Vigo, Vigo, Spain]
Limiting Amplifier is
digitally programmable - 06/05/98 EDN Design
Idea (Page contains several design ideas, please scroll to find this one) Amplitude limiters are
necessary in many systems, such as radar and FM receivers, for which the system cannot allow the
amplitude of the signal to exceed the given positive, negative, or both limits. In the circuit in Figure
1, Amplifier IC4B's maximum output is digitally programmable over ±2 to ±10V in 2n steps, where n is the
number of bits of the DAC. IC1, a precision 10V reference, provides a full-scale reference current, IREF=VREF/R1=2
mA, to IC2, a multiplying DAC.
[by V Manoharan, Naval Physical and Oceanographic Laboratory, Kochi,
Limiting Amplifier Makes Efficient A/D-Converter Drive - 09/02/96 EDN Design Idea Limiting Amplifiers are useful for protecting circuitry that
has a limited input range. A classic example is an input buffer for an A/D converter. Many A/D converters
are susceptible to damage if the input significantly exceeds
[by Mark Amarandos, Harris Semiconductor,
Costa Mesa, CA]