IC-MQF_15 Datasheet, PDF (35/38 Pages) IC-Haus GmbH – Sin/Cos INTERPOLATION IC WITH RS422 DRIVER

iC-MQF PROGRAMMABLE 12-BIT ^preliminary
Sin/Cos INTERPOLATION IC WITH RS422 DRIVER
GENERAL APPLICATION HINTS
Rev C1, Page 35/38
Refer to the datasheet of iC-MQ.
APPLICATION NOTES: SIGNAL CONDITIONING
Regarding a description of the principle signal conditioning procedure refer to the datasheet of iC-MQ.
Signal Conditioning Example 1:
Photodiode array connected to current inputs, LED supply with constant current source
Step
1.
Operating Mode
2.
Test 5
Test 5
Calibration 2
Test 5
3.
Test 5
Test 5
Calibration 2
Test 5
4.
System Test
5.
Calibration 2
6.
System Test
Calibration and Signal
Presets
VOS12= 0x3, GF1= 0x400, VDC1= 0x200, OF1= 0x0, GF2= 0x10, VDC2= 0x200, OF2= 0x0
Example: LED current approx. 6.25 mA
ACOT(1:0)= 0x2 (constant current source), ACOR(1:0)= 0x3 (range 50 mA), ACOS(4:0)= 0x04
(value 12.5)
Calibration of Channel 1:
Parameter GR12: Adjust the diff. signal at PA vs. NA to approx. 6 Vpp amplitude
Parameter GF1: Adjust the diff. signal at PA vs. NA to exactly 6 Vpp amplitude
Parameter VDC1: Minimize the AC fraction of VDC1 at PZ (ripple < 10 mVpeak)
Parameter OR1, OF1: Minimize the DC fraction of the diff. signal PA vs. NA (< 5 mVdc)
Calibration of Channel 2:
Parameter GF2: Adjust the diff. signal at PB vs. NB to exactly 6 Vpp amplitude
Parameter VDC2: Minimize the AC fraction of VDC2 at NZ (ripple < 10 mVpeak)
Parameter OR2, OF2: Minimize the DC fraction of the diff. signal PB vs. NB (< 5 mVdc)
1. Iteration, Calibration of Channel 1 vs. Channel 2:
Parameter OF1: Adjust duty ratio of A₄ at PA to 50 %
Parameter OF2: Adjust duty ratio of B₄ at PB to 50 %
Parameter PH12: Adjust duty ratio of A₈ at NA to 50 %
Parameter GF1: Adjust duty ratio of B₈ at NB to 50 %
Repeated Adjustment of Intermediate Voltages, VDC1 and VDC2:
Parameter VDC1: Minimize the AC fraction of VDC1 at PZ
Parameter VDC2: Minimize the AC fraction of VDC2 at NZ
2. Iteration, Calibration of Channel 1 vs. Channel 2:
Parameter OF1: Adjust duty ratio of A₄ at PA to 50 %
Parameter OF2: Adjust duty ratio of B₄ at PB to 50 %
Parameter PH12: Adjust duty ratio of A₈ at NA to 50 %
Parameter GF1: Adjust duty ratio of B₈ at NB to 50 %
Table 60: Conditioning example 1