HIGH RIPPLE-REJECTION LOW DROPOUT MIDDLE OUTPUT CURRENT CMOS VOLTAGE REGULATOR
Rev.2.2_01
S-1135 Series
3. ON / OFF pin
This pin starts and stops the regulator.
When the ON / OFF pin is set to OFF level, the entire internal circuit stops operating, and the built-in P-channel MOS
FET output transistor between the VIN and VOUT pins is turned off, reducing current consumption significantly.
Since the S-1135 Series A / B / E / F type has a built-in discharge shunt circuit to discharge the output capacitance,
the VOUT pin is forcibly set to VSS level. In the S-1135 Series C / D / G / H type, the VOUT pin is set to VSS level
through several hundred kΩ internal divided resistors between the VOUT and VSS pins. Note that the current
consumption increases when a voltage of 0.3 V to 1.0 V (Ta = 25°C) is applied to the ON / OFF pin.
The ON / OFF pin is configured as shown in Figures 21 and 22. 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 VSS level. In the S-1135 Series B / D / F / H type, the ON / OFF pin is not internally pulled up or pulled
down, so do not use the ON / OFF pin in the floating status. When not using the ON / OFF pin, connect it to the VIN
pin in the product B / D type, and connect it to the VSS pin in the F / H type.
Table 11
Product Type
A / B / C / D
A / B / C / D
E / F / G / H
E / F / G / H
ON / OFF Pin
“H”: ON
“L”: OFF
“H”: OFF
“L”: ON
Internal Circuit
Operate
Stop
VOUT Pin Voltage
Set value
Current Consumption
*1
ISS1
VSS level
VSS level
Set value
ISS2
ISS2
ISS1
Stop
Operate
*1
*1. Note that the IC’s current consumption increases as much as current flows into the pull-up / pull-down
resistor 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 (Refer to Figure 21).
(1) S-1135 Series A / C / E / G type
(2) S-1135 Series B / D / F / H type
VIN
VIN
E / G type
ON / OFF
ON / OFF
A / C type
VSS
VSS
Figure 21
Figure 22
21
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