S-8365AAABA-M5T1Y2 Datasheet, PDF (15/63 Pages) Seiko Instruments Inc – PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER

STEP-UP, SUPER-SMALL PACKAGE, 1.2 MHz PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
Rev.2.1_01
S-8365/8366 Series
3. Shutdown pin
This pin stops or starts step-up operations.
3.1 Without ON/OFF pin pull-down
When this pin is set to the low level, the voltage of the EXT pin is fixed to 0 V, and the external transistor and all
internal circuits stop, substantially reducing the current consumption.
Do not use the ON/OFF pin in a floating state because it is set up as shown in Figure 11 and is not internally
pulled up or down. Do not apply a voltage of between 0.3 V and 0.75 V to the ON/OFF pin because applying
such a voltage increases the current consumption. If the ON/OFF pin is not used, connect it to the VDD pin.
Table 11
ON/OFF pin
CR Oscillation
Circuit
Output Voltage
“H”
Operates
Set value
“L”
Stops
≅VIN^*1
*1. Voltage obtained by subtracting the voltage drop due to the DC resistance of the inductor and the diode
forward voltage from VIN.
VDD
ON/OFF
VSS
Figure 11
3.2 With ON/OFF pin pull-down
When the ON/OFF pin is set to the low level, the voltage of the EXT pin is fixed to 0 V, and the external
transistor and all internal circuits stop substantially reducing the current consumption.
The ON/OFF pin is set up as shown in Figure 12 and is internally pulled down by using the depression
transistor, so all circuits stop even if this pin is floating. Do not apply a voltage of between 0.3 V and 0.75 V to
the ON/OFF pin because applying such a voltage increases the current consumption. If the ON/OFF pin is not
used, connect it to the VDD pin.
Table 12
ON/OFF Pin
CR Oscillation
Circuit
Output Voltage
“H”
Operates
Set value
“L”
High-Z
Stops
Stops
≅VIN^*1
≅VIN^*1
*1. Voltage obtained by subtracting the voltage drop due to the DC resistance of the inductor and the diode
forward voltage from VIN.
VDD
ON/OFF
VSS
Figure 12
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