External Power-Supply Header - Renesas RL78/G1N User Manual

RL78/G1N Fast Prototyping Board 5. User Circuits
5.11

External Power-Supply Header

When operating the RL78/G1N at a desired external input voltage, or when more current is required than the
USB is capable of supplying, use the external power-supply header (J4) to supply power. The usable voltage
range is from 2.25 V to 5.5 V.
When this header is to be used, short-circuit pins 1 and 2 of the power-supply selection header (J5) (see
Figure 5-5). In addition, short-circuit the emulator reset header (EJ2), remove SS5, and make EJ1 open-
circuit, as described in section 5.9, Emulator Reset Headers, to place the emulator in the forced reset state.
Power cannot be supplied from the USB at this time. Remove the USB cable.
Figure 5-5 shows the position of the external power-supply header (the J4 header component is not mounted).
When power is being supplied through the external power-supply header, the connection of Arduino Nano
shields for which the I/O voltage is 3.3 V is not possible.
Power-supply
selection
header (J5)
External
power-supply
header (J4)
Emulator reset
Emulator reset
headers (EJ1
header (EJ2)
and SS5)
Figure 5-5 Position of the External Power-Supply Header
R20UT4810EJ0100 Rev.1.00 Page 12 of 27
Jun.16.20