Renesas RH850/U2A 144pin, Руководство пользователя

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RH850/U2A 144pin 3. Power Supply
R20UT5089ED0101 Rev.1.01 Page 12 of 56
July 08, 2022
3.3 Device Core Voltage (VDD) Selection
The device core voltage VDD (typ.1.12 V) can be
•
supplied from external via CN11 (voltage IN_1v12)
•
generated from the P3V3 power rail by use of the on-board voltage regulator IC16 (voltage reg_vcc_VDD)
•
generated by the on-chip Switching Voltage Regulator (SVR) in combination with device external power transistors
TR1, TR2 (voltage SVR_OUTPUT)
Note
The IN_1v12 and reg_vcc_VDD voltages have a level of typical 1.12 V, which is higher than the typical
device core voltage VDD of 1.09 V. The 30 mV difference is supposed to compensate voltage drops over the
power rails on the board, in particular over the jumpers.
Selection of the VDD source is achieved by use of the jumpers JP23 and JP16:
•
JP23[2-1]: VDD = 1.12 V (VDDs) from
−
JP16[2-1]: VDDs = reg_vcc_VDD from on-board voltage regulator IC16
−
JP16[2-3]: VDDs = IN_1v12 from external supply CN11
•
JP23[2-3]: VDD = 1.09 V (SVR_OUTPUT)
3.4 Current Measurement Bridges
The total current of the 5V0 and 3V3 power rails can be measured by replacing the jumpers
JP4 and JP5 with a current meter.
Accordingly, the total current via the A/D Converter's supply voltages A5V0 and A3V3 can be
measured via the jumpers JP30 and JP31 respectively.
The current of particular power supply pins of the device can be measured via their respective
supply selection jumpers, refer to Figure 3.1 Voltage distribution .
3.5 Power Supply LEDs
The following green LEDs indicate the presence of various voltages on the piggyback board:
•
LED11 for 5.0 V power rail P5V0
•
LED12 for 3.3 V power rail P3V3
•
LED10 for 1.12 V device core voltage VDD
CORE VOLTAGE SELECTION
reg_vcc_VDD SVR_OUTPUT
1.09V
1.12V
IN_1v12
VDDs
1.12V 1.12V
1.12V
VDD
JP23 JP16
3
2
1
3
2
1
3
2
1
3
2
1
Figure 3.2 Device core voltage (VDD) selection