Hi, I am using VSP3210 with ILX511 CCD and the circuit is not working. Does anyone have a sample circuit design? Thanks! Tom
Hi Tom,
Is it possible for you to send a block diagram or schematic of your circuit? There are a lot of reasons it could be non-functional. either schematic, timing, etc.
A good place to start is to measure the CCD output and determine if any signal is coming out. You should have something that looks roughly like the CCD output waveform on page 6 of the VSP3210 data sheet. Second, verify the sampling pulses CK1 and CK2 are approximately as shown in the same diagram.
Regards,
Werner
Hi Werner,
Thanks a lot. I have found out why: There is a one byte shift when configuring the registers and that has caused the trouble. It is now working. The CDS does not seem to offer noticable improvement over direct detection with ILX511 CCD. But it is a different matter now.
Tom
The CDS should offer improvement over direct detection of the CCD signal, reflected in less noise. The noise is reflected as a lower standard deviation when you measure a histogram of the digitized output values.
An initial test is to start in 1-channel mode, verify the CK1 and CK2 pulses have the approximate timing as shown in page 6 of the data sheet. With the input grounded, the digital data should have a standard deviation of approx 8 LSB's at a gain of 0 dB. The histogram should look like a normal (Gaussian) distribution.
Hi,
This is the first time i am working with a ccd sensor.Can anyone tell me if i can use vsp 2582 as afe for the ILX511 ccd?
I also have trouble in understanding the timing connections for the AFE. Can anyone help me by providing a schematic for the same?
Shilpa
Shilpa,
THe VSP2582 can be used in this application. It is recommneded however that the clock used for the SPI interface on the VSP2582 is less than th eMCLK. SO if th eMCLK used is 2MHz (max clock rate for the LX511), then the Serial clock, SCK, should be less than 2MHz.
hi,
Thanks for the reply.The datasheet for the VSP2582 however specifies a frequency of 20 MHz for the SCLK.I am using an input Clock frequency of 1MHz for the ILX511and a read out rate of 2.4MHz.Should i be taking a frequency lesser than 1MHz for the SCLK?
Can you explain how the procedure for testing the AFE output?
regards.
For the VSP2582 the SCLK spec is the max freqency. It can be run much slower. For a 1MHz clock frequency, Iwould recommend 100KHz or so.
For testing the AFE output, it depends on what you are trying to measure. The simplest test is to simply ground the input through a 0.1uF cap and then opearte the device with clocks, SHP, SHD etc. The output should be a gaussian centered at approx the setting of the OB register and with a width of a few LSB, reflecting the random noise of the input stage.
Werner,
Thanks for the response.I will be going ahead with the same frequency suggested.How much time will it take for the ccd output to be processed by the AFE at these frequencies?
For the AFE clock signals like the SHP,SHD,CLPDM.CLPOB etc. do i have to send the clock signals from the processor based on the timing diagrams in the datasheet?
Could you kindly suggest some resources to understand the operation of the AFE and how to build the complete circuit for the same.I don't seem to understand the datasheet very well.
I am use the VSP3210 and the CCD of ILX511,now the circuit not working ,please see the schematic of my circuit ,can you tell me whether is right?
1、now ,i can write the register correct,i can set the offset voltage and the PGA gain. while I configure the register of 8bits data ,I send a serial data from D9 to D0 of 10bits,is it right?
2、while I use the external reference of 1.25V, in the circuit can I test the voltage? what is CM pin function?
Tom Jiang