PWM and Analog Inputs
www.ti.com
5.2
Analog Input
The following instructions are provided to use an external analog source to drive the DRV2700:
1. Disconnect the MSP430 output pin from the DRV2700 input pins by removing jumper JP1
2. Connect the DRV2700 EN signal:
(a) Use the onboard MSP430 and GUI to control the EN pin by connecting JP3 between EN and MSP
(b) EN the output all the time by connecting JP3 between PU and EN
(c) Use an external control signal by connecting source to the middle header of JP3
3. Connect the analog input signal to TP1 (INPUT). Note, the default input range is from 0–3.3 V (same
as PWM signal). Therefore, if a voltage divider is needed, R21 and R2 can be changed accordingly.
4. Enable the power supply
5. Enable the analog input signal (and EN)
Figure 11
and
Figure 12
show waveforms using an external sine wave.
V
DD
= 5 V
C
(LOAD)
= 22 nF
V
HV
= 0 to 500 V
V
DD
= 5 V
C
(LOAD)
= 22 nF
V
HV
= 0 to 500 V
Input Frequency =
10 Hz
Figure 12. 100-Hz Input Signal
Figure 11. 10-Hz Input Signal
16
DRV2700EVM-HV500 High Voltage Piezo Driver Evaluation Kit
SLOU407A – April 2015 – Revised May 2015
Submit Documentation Feedback
Copyright © 2015, Texas Instruments Incorporated