S1135 Datasheet, PDF (23/48 Pages) Seiko Instruments Inc – HIGH RIPPLE-REJECTION LOW DROPOUT

HIGH RIPPLE-REJECTION LOW DROPOUT MIDDLE OUTPUT CURRENT CMOS VOLTAGE REGULATOR
Rev.2.2_00
S-1135 Series
5. Overcurrent protection circuit
The S-1135 Series has an overcurrent protection circuit having the characteristics shown in “1. Output Voltage vs.
Output Current (When Load Current Increases) (Ta = 25°C)” in “ Characteristics (Typical Data)”, in order to
protect the output transistor against an excessive output current and short circuiting between the VOUT and VSS
pins. The current when the output pin is short-circuited (I_short) is internally set at approx. 100 mA (typ.), and the normal
value is restored for the output voltage, if releasing a short circuit once.
Caution
This overcurrent protection circuit does not work as for thermal protection. If this IC long keeps
short circuiting inside, pay attention to the conditions of input voltage and load current so that,
under the usage conditions including short circuit, the loss of the IC will not exceed power
dissipation of the package.
6. Pull-down / pull-up resistor (S-1135 Series A / C / E / G type)
In the S-1135 Series A / C / E / G type, the ON / OFF pin is internally pulled up to the VIN pin or 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-up / pull-down resistor of 2.2
MΩ (typ.) when; the ON / OFF pin is connected to the VIN pin in the A / C type, the ON / OFF pin is connected to the
VSS pin in the E / G type.
Seiko Instruments Inc.
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