S-19253E12H-U5T1U Datasheet, PDF (14/30 Pages) Seiko Instruments Inc – CMOS VOLTAGE REGULATOR WITH SOFT-START FUNCTION

FOR AUTOMOTIVE 105°C OPERATION LOW DROPOUT HIGH OUTPUT CURRENT CMOS VOLTAGE REGULATOR WITH SOFT-START FUNCTION
S-19253xxxH Series
Rev.1.0_00
4. Discharge shunt function
The S-19253xxxH Series has a built-in discharge shunt circuit to discharge the output capacitance. The output
capacitance is discharged as follows so that the VOUT pin reaches the V_SS level.
(1) The ON / OFF pin is set to OFF level.
(2) The output transistor is turned off.
(3) The discharge shunt circuit is turned on.
(4) The output capacitor discharges.
The S-19253xxxH Series allows the VOUT pin to reach the V_SS level rapidly due to the discharge shunt circuit.
S-19253xxxH Series
Output transistor: OFF
*1
VIN
VOUT
ON / OFF
ON / OFF circuit
ON / OFF pin: OFF
Discharge shunt circuit
: ON
*1
Current flow
Output
capacitor
(C_L)
VSS
GND
*1. Parasitic diode
Figure 12
5. Pull-down resistor
The ON / OFF pin is internally pulled down to the VSS pin in the floating status, so the VOUT pin is set to the V_SS
level.
Note that the IC's current consumption increases as much as current flows into the pull-down resistor of
4.0 MΩ typ. when the ON / OFF pin is connected to the VIN pin.
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