Other Parts Discussed in Thread: DLPC3479, DLP4710, DLPA3005
Hi TI experts,
I have encountered another two minor issues when using DLP4710LC develop projector.
The first issue is that the LED will suddenly light up for little time after power on, although the DLPC3479 boot config is to turn off the LED. I measured the GATE of LED driver MOSFET waveform as below.
Figuare 1
I think whether the ture on LED signal is abnormal.
The second issue is after sending the RUNONCE(36 9E 00 00 in hex) by IIC command, the execute time is different because of different pattern time setting.
For example, I have set the pattern timing is Pre-Exposure Dark Time 500us, the Exposure Time 2500us, the Post-Exposure Dark Time 1000us. Then I measured the signal of IIC and Trig2_OUT with oscilloscope and the screenshot is as figuare 2. The yellow line is the IIC command waveform, and the blue line is the Trig2_OUT waveform. The delay time is about 4.5ms from the IIC command sending completed to the first image exposured.
Figure 2
After I changed the Post-Exposure Dark Time 6000us, the signal waveform of IIC and Trig2_OUT is as figuare 3. The delay time increased to about 9.5ms.
Figuare 3
Then I changed the Post-Exposure Dark Time 10000us, the signal waveform of IIC and Trig2_OUT is as figuare 4. The delay time increased to about 13.5ms.
Figuare 4
When I changed the Post-Exposure Dark Time 15000us, the signal waveform of IIC and Trig2_OUT is as figuare 5. The delay time increased to about 18.5ms.
Figuare 5.
The delay time increasing will affect the rate of DLP4710 projector display.
Thanks for any help.
