XC641A Datasheet, PDF (9/20 Pages) Torex Semiconductor – CMOS Low Power Consumption

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GNotes on Use :
IC
1. Please sufficiently strengthen the GND wiring and the power supply (VDD) line, as when the power
supply line impedance is high, the voltage regulators and detectors are prone to oscillation leading
to possible instability.
2. In order to lower the power supply line impedance, we recommend that a capacitor of 10µF (Tantalum)
or more be connected at the shortest point possible between the VDD pin and the GND pin.
3. To protect the IC from surge at the input pin, an input protect diode is built-in. Therefore, do not
apply voltages that exceed the VDD pin voltage.
4. Please ensure that the sum total of the IC's power consumption does not exceed the stipulated figure
for total continuous power dissipation ( Pd ).
Pd < P1 + P2 + P3 + P4 + P5 + P6
The following equations can be used to calculate the IC's power consumption :
Regulator 1 : P1 = ( VDD - 0.6V ) x IEXT1, IEXT1 to IOUT1 / hFE
Regulator 2 : P2 = ( VDD - 0.6V ) x IEXT2, IEXT2 to IOUT2 / hFE
Regulator 3 : P3 = ( VDD - VOUT3 ) x IOUT3
Regulator 4 : P4 = ( VDD - VOUT4 ) x IOUT4
Detector 1 : P5 = VDOUT1 x IDOUT1
Detector 2 : P6 = VDOUT2 x IDOUT2
Voltage Regulator 1, 2 ( External transistor type )
1. In order to prevent regulator oscillation ( caused by power supply impedance ), we recommend
that a capacitor of 10µF (Tantalum) or more be connected between the external transistor's emitter
and the GND pin.
2. In order to prevent regulator phase compensation, we recommend that a capacitor of 10µF (Tantalum)
or more be connected between the IOUT1, IOUT2 pins and the GND pin.
3. In order to prevent oscillation we recommend that a resistor of around 200kΩ be connected between
the external transistor's base pin and emitter pin.
Voltage Regulator 3, 4 ( Built-in transistor type )
1. Please connect a capacitor of 1µF (Tantalum) or more between the voltage regulator's output pins
( OUT3, OUT4 ) and the GND pin.
2. In order to prevent regulator oscillation ( caused by power supply impedance ), we recommend that
a capacitor be connected between the VDD pin and the GND pin.
3. Since a short circuit protector is not built-in, when the OUT3 or OUT4 pin is short circuited to the
GND pin, resulting surge current may damage the IC.
Voltage Detectors
1. In order to prevent regulator oscillation ( caused by power supply impedance ), we recommend
that a capacitor be connected between the VDD pin and the GND pin.
2. Should the VDD pin voltage become excessively low, we recommend that a Schottky Diode be
connected between the CD1 pin and the VDD pin, in order to prevent voltages over the established
VDD + 0.3V being applied to the capacitor connection pin ( CD1 ).
Please use a Schottky Diode of VF = 0.3V ( IF = 10mA ). If a large reverse current, IR (max.), is used,
the delay circuit current will increase and delay time will be shortened.
3. When not using the delay circuit, please use the IC with the CD1 pin open.
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