S-8540 SII [Seiko Instruments Inc], S-8540 Datasheet - Page 12

• Manufacturer Part Number: S-8540
• Description: STEP-DOWN, 600 kHz PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
• Manufacturer: SII [Seiko Instruments Inc]

12
STEP-DOWN, 600 kHz PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
S-8540/8541 Series
3. ON/ OFF pin (shutdown pin)
This pin deactivates or activates the step-down operation.
When the
switching transistor to go off. All the internal circuits stop working, and substantial savings in current
consumption are thus achieved.
The
internally, please avoid operating the pin in a floating state. Also, try to refrain from applying a voltage of
0.3 to 1.8 V to the pin, lest the current consumption increase. When this
leave it coupled to the VIN pin.
ON
ON/OFF
ON
/
OFF
“H”
“L”
/
OFF
ON
Pin
/
Figure 10
pin is configured as shown in Figure 10 . Since pull-up or pull-down is not performed
OFF
CR Oscillation Circuit
pin is set to "L", the V
Deactivated
Activated
Table 7
VSS
VIN
Seiko Instruments Inc.
Output Voltage
Set value
IN
OPEN
voltage appears through the EXT pin, prodding the
ON
/
OFF
pin is not used,
Rev.3.2
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