Sense Circuits - Renesas RAJ306101 User Manual

RAJ306101 RSSK User's Manual
4.3.2

Sense Circuits

4.3.2.1 Current Sense (Internal)
This Evaluation Board is also available to detect U, V, and W phase currents by connecting U, V, and W
phase shunt resistors to the built-in differential amplifier of the smart gate driver. The differential amplifiers are
disabled in the sample program. When using the built-in differential amplifier for the motor current sense, refer
to Figure 4-7 to mount and remove 0[Ω] resistors, and change the smart gate driver register settings. The
relation between the phase current (Iin) flow to the shunt resistor (Rs) and the voltage input to the MCU (Vout)
is expressed by EQ 4-1.
Vout [ ���� ] = Iin [ ���� ] × Rs [ ���� ] × Gain [ ����/���� ] + �
EQ 4-1
R12UZ0129EJ0100 Rev.1.00
Nov 1, 2023
Iin Rs
Iin : Current flow to shunt resistor
Rs : Shunt resistor (0.05[Ω])
Gain: Differential amplifier gain
VDD : Smart Gate Driver VDD pin voltage
Vout : Voltage applied to A/D converter input port of the MCU
Figure 4-7 Current Sense Circuits (Internal)
VDD [ ���� ]
�
2
Smart
Gate
Driver
+
Diff.
Amp.
-
Vout
Chapter 4. Peripheral Circuits
VDD
I
U
I
V
I
W
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