Renesas 38K0, Instruction Manual

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RENESAS USB F
38K0/38K2 Group M3A-8K02
ull-Speed Microcomputers
8
1.5 Power Supply
M3A-8K02 can run on either self-power (external supply of 5V) or bus-power (VBUS power from USB
up-port).
* Self-Power
To run M3A-8K02 on self-power, connect the external supply through TP1 (1) or the DC jack (2), as shown in
Figure 1.5. The polarity of the DC jack is “GND” internally and “+” externally.
The SELF-POWER switch (S2 in 3) turns the self-power ON/OFF. When switched to ON, the SELF-POWER
lamp (LED1 in 4) goes on, and voltage is supplied to the board from the external source
(Note 1)
. In addition, by
connecting Jumper PowerINT (JP1 in 5), ON/OFF events can be assigned to the INT0 pin.
Note 1: This board is not protected against counter power supply
.
* Bus-Power
If there is no external power supply, the board goes to the bus-power mode and receives power from the USB.
If the board is connected to a PC without external power supply, the USB-POWER lamp (LED4 in 6) will go on
and power will be supplied via the USB VBUS.
* Receiving power from self-power and bus-power ports:
If power is supplied from both self-power and bus-power ports, the board will automatically connect to the
self-power supply.
+
GND
3. Self-Power Switch
ON/OFF switch for external
power supply
5. Connection to INT0
Assigns external power
ON/OFF event to INTO
interrupt.
6. BUS-POWER Lamp
Turns on when bus power is in use.
4. SELF-POWER Lamp
Turns on when external power
is ON.
2. DC Jack
Jack for external power
supply connection
GND +
1. 5V input port for
electrical clips
Pin for external power
supply connection
Figure 1.5 Power Supply Areas