SM8172A Datasheet, PDF (9/17 Pages) Nippon Precision Circuits Inc – 2-output Power Supply IC

SM8172A
12-4. Supply Undervoltage Lockout Function
In addition to the reset function, when the VIN2 supply falls below 3.0V (typ), the undervoltage lockout func-
tion operates, stopping the DC/DC converter and series regulator outputs. When the VIN2 supply subsequently
rises above 3.2V (typ), the outputs start again.
VRESETNH
VRESETNL
VUVLOH
VUVLOL
VIN2
VRESETN
(Pull-up)
Reset return delay time
65msec (typ)
VDCOUT
VLDOUT
LDOUT (regulator output)
DCOUT (DC/DC output)
800µsec (typ)^*1
70µsec (typ)^*1
LDOUT (regulator output)
DCOUT (DC/DC output)
DC/DC soft start time^*2
0.6msec (typ)
LDO soft start time^*2
1msec (typ)
DC/DC, regulator output stop
by UVLO lockout
*1. A time interval example for a typical application circuit with no load. The series regulator and DC/DC converter output voltage rise times may vary with
the load current, output capacitance, and other conditions.
*2. The soft start time is the interval during which the output current is limited internally in the IC, and is different from the series regulator and DC/DC con-
verter output raise time.
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