Circuit Function - Renesas RL78/G1F User Manual

RL78/G1F Motor Driver Board GB01

8. Circuit Function

8.1 Inverter Control Circuit
The inverter control circuit control the motor using six Power MOS-FETs. The Power MOS-FETs use the 6-
phase timer outputs from the microcontroller via the predriver IC.
The inverter control circuit inputs the DC line voltage, U-phase voltage, V-phase voltage, W-phase voltage,
and shunt current to the A/D pins of the microcontroller. The analog values of each voltage and shunt current
can thus be measured. See sections 8.2 and 8.3 for details about how to detect the current and voltage,
respectively. The inverter control circuit also has a function to detect the overcurrent from the U-phase, V-
phase, and W-phase shunt current.
Figure 8-1 shows a schematic diagram of the inverter control circuit. Note that the inputs to the A/D pins
may actually pass through a voltage diver or an offset device. See the circuit diagram for details.
PWM input
POWER
MOS- FET
Shunt current
(MCU built-in amplifier connection)
R12UT0012EJ0100 Rev.1.00
20.10.2020
UP VP
UN VN
PGAG PGAI
OP-Amp
Figure 8-1 Schematic Diagram of Inverter Control Circuit
WP
WN
I _OPA
V
OP-Amp
I _OPA
U
OP-Amp
User's Manual
DC Bus voltage
V
BUS
Motor
Phase
voltage
V
U
V
V
Midpoint
V
W
voltage
V
N
Shunt current
(Via amplifier)
I _OPA
W
Page 13 of 32