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9
KX-UT670RU
4.2.1.
12V
→ 3.3V
IC9 starts operating under the input voltage to pin2(VIN) and "High" input level to pin1(CE).
The output voltage is adjusted to 3.3V by the following operation.
Output voltage is divided by R38,R40 and R39.
The output voltage is adjusted so that the voltage(to pin6(VFB) may become 0.8V.
The output voltage is adjusted to 3.3V by the following operation.
Output voltage is divided by R38,R40 and R39.
The output voltage is adjusted so that the voltage(to pin6(VFB) may become 0.8V.
4.2.2.
12V
→ 5V
Basically the circuit operation is the same as 4-2-1.
Only resistor for the output voltage setting is different.
Only resistor for the output voltage setting is different.
Pin1(CE) is controlled by "Power Down Detection".
This circuit is used for 5V power supply circuit to extend the hold time of 3.3V at power failure.
This circuit is used for 5V power supply circuit to extend the hold time of 3.3V at power failure.
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