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CM431L
LOW VOLTAGE ADJUSTABLE SHUNT REGULATOR
APPLICATION CIRCUIT
Notes for Application Circuit:
1) Set VOUT according to the following equation:
VOUT =VREF ( 1 + R1/R2 ) +IREF R1
2) Choose the value for R as follows:
• The maximum limit for R should be such that the
cathode current, Iz, is greater than the minimum
operating current(80
μA)at VIN(min).
• The minimum limit for R should be such that Iz
does not exceed 100mA under all load conditions,
and the instantaneous turn-on value for Iz does not
exceed 150mA. Both of the following conditions
must be met:
Rmin ≥
(
to limit instantaneous turn-on Iz)
VIN(max)
150mA
2006/02/10 Rev. 5
Champion Microelectronic Corporation
Page 9
Rmin ≥
(
to limit Iz under normal operating conditions)
VIN(max)–VOUT
IOUT(min)+ 100mA