Difference between revisions of "MCE Timing Diagram"

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The coadd window takes the 4 clock cycles of ADC latency into account, i.e., When the coadd window is asserted at clock cycle 40 in the diagram above, the samples are stored starting clock cycle 44.
 
The coadd window takes the 4 clock cycles of ADC latency into account, i.e., When the coadd window is asserted at clock cycle 40 in the diagram above, the samples are stored starting clock cycle 44.
  
Bias Card DACs have ~400ns settling delay (see FULL-SCALE STEP RESPONSE on page 6 [http://datasheets.maxim-ic.com/en/ds/MAX5441-MAX5444.pdf here]
+
Bias Card DACs have ~400ns settling delay (see FULL-SCALE STEP RESPONSE on page 6 [http://datasheets.maxim-ic.com/en/ds/MAX5441-MAX5444.pdf here],
 
Address Card and Readout Card DACs have a settling delay of 11 ns.
 
Address Card and Readout Card DACs have a settling delay of 11 ns.

Revision as of 14:13, 26 April 2011

The following timing diagram is generated by simulating MCE firmware using ModelsimTM, therefore, it does not include the analog circuit delays (DAC delay, RC filters, settling time, etc) into account.

Frame timing diagram.png Parameters used for this simulation:

row_len 100
num_rows 33
sample_dly 40
sample_num 10
servo_mode 3
Address Card enbl_mux 1
Bias Card enbl_mux 1
RC firmware rev. 5.1.2
BC firmware rev. 5.0.6
AC firmware rev. 5.0.3
CC firmware rev. 5.0.7

Note that Bias Card DACs (MAX5443) latch on CS’s low-to-high transition. Address Card DACs are clocked on the negative edge of the main clock.

Under Address Card section, both DAC_clk(0) and DAC_clk(32) are shown. This indicates that first, the previous row's DAC (32 in this case) is turned off and then the new DAC (0 in this case) is turned on. All Address-Card DACs are off for 2 clock cycles.

The coadd window takes the 4 clock cycles of ADC latency into account, i.e., When the coadd window is asserted at clock cycle 40 in the diagram above, the samples are stored starting clock cycle 44.

Bias Card DACs have ~400ns settling delay (see FULL-SCALE STEP RESPONSE on page 6 here, Address Card and Readout Card DACs have a settling delay of 11 ns.