Cpu Power Supply Select Jumper (Jp1) - Renesas M3A-HS37 User Manual

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3.2.1 CPU Power Supply Select Jumper (JP1)

Set JP1 to switch 3.3 V or 5 V supplied to the SH7137 MCU.
The jumper switches the supply voltage for the SH7137 (U1), M5M5256DFP-VP70GI (SRAM, U2), and the power supply on
the CPU side of the SN74LVC2T45DCT (U13, and U14, RCAN level shifter). The supply voltages for other components are not
changed.
Figure 3.2.2 shows the CPU power supply select jumper assignments. Table 3.2.1 lists the CPU power supply select jumper
setting.
No.
JP1
PWRSEL
indicates the default setting.
Note: Do not make any change with the jumper setting while the M3A-HS37 is operating. Ensure to turn the power OFF
before changing the setting.
Rev.1.00 Oct 09, 2008
REJ11J0021-0100
Figure 3.2.2 CPU Power Supply Select Jumper Assignments (JP1)
Table 3.2.1 CPU Power Supply Select Jumper Setting (JP1)
Setting
1-2
+5 V is supplied to CPU and SRAM
2-3
+3.3 V is supplied to CPU and SRAM
Open External power supply voltage (supplied from J5 or H9)
Do not leave the jumper open not supplying the power from an external
source.
Operational Specifications
3.2.1 CPU Power Supply Select Jumper (JP1)
Function
3-17