Mcu Native Pin Access; Breakout Pin Headers; Mcu Current Measurement; Figure 17. Native Pin Access J3 And J4 - Renesas RA4 Series User Manual

Renesas RA Family FPB-RA4E1 v1 – User's Manual

6. MCU Native Pin Access

Figure 17. Native Pin Access J3 and J4

6.1 Breakout Pin Headers

The FPB-RA4E1 board pin headers (not fitted), J3 and J4, provide access to all RA MCU interface signals,
and to voltages for all RA MCU power ports. Each header pin is labelled with the voltage or port connected to
that pin. Refer to the RA4E1 MCU Group User's Manual for details of each port function, and the FPB-
RA4E1 board schematic for pin header port assignments.
The placement of the breakout pin headers allows for a standard 2.54 mm (0.100") centre breadboard to be
placed on both pin headers simultaneously. This can be used for prototyping and testing of custom circuitry
for use with the RA4E1 MCU.

6.2 MCU Current Measurement

Included near the RA MCU is resistor R3 and test connector CN1 (not fitted) to measure the MCU core
current.
Resistor R3 is 0 Ω (SMD 0805) as supplied. It should be removed in order to measure the current
consumption using an ammeter connected between CN1 pins 1 and 2.
Alternatively, it could be removed and replaced with a suitable low value resistor (such as 100 mΩ), and then
a voltmeter used to measure the voltage between CN1 pins 1 and 2. The current drawn by the MCU can
then be calculated using Ohm's Law.
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Sep.07.21