SLVUA41E
3
1.1 Overview
The DRV8308EVM makes it easy to evaluate the DRV8308 device with different BLDC motors. The kit
includes the main PCB, a BLDC motor that uses DRV5013 Hall Effect sensors, a micro USB cable, and
a downloadable Windows application that controls and monitors the DRV8308 with a graphical user
interface (GUI).
DRV8308
FG/TACH (optional)
Hall signals & power
USB
input
USB-to-serial
UART
5V
LDO
3.3V
MSP430
data
Configuration
jumpers
Socket for
EEPROM
data
External
clock
input
Bus isolation jumpers
SPI
control
signals
Hall inputs
FG
input
9
R
ISENSE
VM
FETs
Phase
inputs
BLDC
Motor
FG OUT
testpoint
Power supply
Frequency
to voltage
Flutter meter
Oscilloscope
VM
input
Figure 1. DRV8308EVM system diagram
1.2 External lab equipment
1. Power supply
– The supply should be set to a voltage between 8.5V and 32V, and a current of
at least 1A. A higher current setting is better, as that helps maintain a stable VM voltage,
speeds spin-up time, and increases the torque capability. The DRV8308 will limit peak current
to 5A on this board, since the sense resistor is sized at 0.05
Ω, and V
LIMITER
= 0.25V.
2. Flutter meter
– When the motor rotates, it generates a periodic waveform on each Hall phase,
and optionally on the FG line. The DRV8308 register “FGSEL” sets which input to use for the
speed control loop and pass to FGOUT.