DRV8770EVM User's Guide
Trademarks
eZ-FET is a trademark of Texas Instruments.
All trademarks are the property of their respective owners.
1 Introduction
The DRV8770EVM is a complete solution for evaluating the DRV8770 gate driver. This EVM can be used to evaluate all of the features of the DRV8770. The EVM includes an on-board MCU which is used to provide the necessary logic signals to the DRV8770 in order to drive the external H-bridge FETs. The logic signals (INHA, INLA, INHB, and INLB) come from the MCU can the duty cycle can be adjusted via potentiometers on the board.
The DRV8770 can drive an H-bridge with power supply up to 100 V. For voltages above 50-V, proper high voltage safety procedures should be taken.
To expand beyond the included firmware capability, the MSP430 MCU can be reprogrammed through the eZ-FET™ emulation circuit found in most MSP430 Launchpads. We recommend the MSP-EXP430FR5969. Note that a four pin angled male header is required and must be soldered to J21 of this Launchpad from V+ pin to GND pin. We recommend a pin header with pin dimensions similar to 850-10-050-20-001000 (Digikey part number). The U1 MCU must be removed from the Launchpad.
2 PCB Connectors and Headers
The DRV8770EVM top PCB view and top assembly view are shown in Figure 2-2 and Figure 2-1. The board connectors and headers are listed and described in Table 2-1.
Figure 2-1 DRV8770EVM PCB Top View
Figure 2-2 DRV8770EVM Top Assembly
View| Component | Function |
|---|---|
| J1 | PVDD supply connector |
| J7/J8 | Output connector (MOTA, MOTB, PVDD, GND) |
| J2 | Header for GVDD supply selection. If shorted between middle pin and "GVDD_INT" pin, GVDD will come from internal buck converter. If middle pin and "GVDD_EXT" is shorted, GVDD supply will come from external source connected to "GVDD_EXT" red test point. |
| J3 | Connector for programming the MCU on the board. |
| J4 | Header connected to J3 connector. Can manually place jumper wires to Spi-By-Wire pins on the LaunchPad |
| J5 | Main control signal header test poin. |
| J6 | Current sense amplifier (CSA) reference voltage selector header. Short middle pin to "AREF" to set REF voltage of CSA to 1.65-V (mainly used for bi-directional current sensing). Short middle pin to "GND" to set the CSA REF voltage to 0-V. |
| PVDD LED | PVDD LED indication |
| GVDD LED | GVDD LED indication |
| 3.3 V LED | 3.3 V LED indication |
| STATUS LED | MCU STATUS LED indicator. Will turn ON when MCU is working |
| RP1 | Potentiometer for adjusting duty cycle of INHA and INLA |
| RP2 | Potentiometer for adjusting duty cycle of INHB and INLB |
| RP3 | Unused potentiometer. |
