V850E2/Fx4 Application Board User's Manual
4.3 IC Voltage Rails
The Main Board provides several options for powering the board’s integrated circuits. Jumpers
are provided to select from the available voltage sources, or to completely disconnect the rail.
Indicator LEDs, D4 to D7, are provided to easily observe the state of the VDDA, VDDB, VDDIOF
and VBATF voltage rails.
Caution: See precaution 6.2 for details regarding the voltage rail indicator LEDs.
Caution: Ensure that only one voltage source is selected for each voltage rail.
Voltage Rail
Description
Jumper
Setting
Source
1 – 2
VReg output 1
3 – 4
VReg output 2
5 – 6
connector CN7
VDDA
supply voltage to microcontroller
J2
7 – 8
connector CN8
1 – 2
VReg output 1
3 – 4
VReg output 2
5 – 6
connector CN7
VDDB
supply voltage to microcontroller
J3
7 – 8
transistor Q1
VBATF
battery level supply voltage to ICs
J5
1 – 2
connector CN5 or CN6
1 – 2
VReg output 1
3 – 4
VReg output 2
5 – 6
connector CN7
VDDIOF
I/O level supply voltage to ICs
J6
7 – 8
connector CN8
1 – 2
VReg 5 volt output
3 – 4
connector CN7
VDD5F
5 volt supply to ICs
J7
5 – 6
connector CN8
Table 4.
Voltage Rail Selections
4.4 External Power Transistor
The M2 version of V850E2/Fx4 microcontrollers is capable of controlling an external power
transistor to regulate its core logic voltage. Transistor Q1 is provided for use with M2 version
microcontrollers. Jumper J4 can be used to connect the control signal and core logic voltage rail
(PT_CVDD). Jumper J3, described in Table 4, is used to connect the core logic rail to the
microcontroller.
R20UT0009EU0103 Rev.1.03
Page 12
May 21, 2012