HC-55564 Datasheet, PDF (6/9 Pages) Harris Corporation – Continuously Variable Slope Delta-Modulator (CVSD)

HC-55564
The following typical performance distortion graphs were
realized with the test configuration of Figure 7. The
measurement vehicle for Total Harmonic Distortion (THD)
was an HP-339A distortion measurement set, and for 2nd
and 3rd harmonic distortion, an HP-3582A spectrum
analyzer. All measurement conditions were at V_DD = 5V, and
2nd and 3rd harmonic distortion measurements were C-
message filtered. 0dB = 1.2V_RMS.
FUNCT.
GEN.
0.33µF
HC-55564 _0.33µF
5 _{AIN AOUT} 3
1
DEC/ 10
V_DD
11
ENC
13 ^{APT DGND 8}
FZ
2
AGND
C-MES-
SAGE
FILTER
5V
+1.0µF
HP3582A
SPECTRUM
ANALYZER
OR HP339A
DISTORTION
ANALYZER
-10
-20
THD
(dB)
-30
-40
-24
16KHz
32KHz
64KHz
30%
INPUT
FREQ. = 1kHz
10%
3%
-16
-8
INPUT SIGNAL LEVEL (dB)
1%
0
FIGURE 7. TEST AND MEASUREMENT CIRCUIT
FIGURE 8. CVSD SIGNAL LEVEL vs TOTAL HARMONIC
DISTORTION
CVSD INPUT LEVEL vs 2ND AND 3RD HARMONIC DISTORTION
C-MESSAGE WEIGHTED
-10
INPUT
-20 FREQUENCY 1kHz
3RD
16kHz CLOCK
-30
2ND
-40
-50
-24
-17
-11
-3.8
+3.0
INPUT SIGNAL LEVEL (dB)
FIGURE 9A.
CVSD SIGNAL TO 2ND AND 3RD HARMONIC DISTORTION
C-MESSAGE WEIGHTED
-10
V_IN = 0.5V_RMS
-20
16kHz CLOCK
-30
3RD
-40
-50
0
2ND
1000
2000
INPUT FREQUENCY (Hz)
3000
FIGURE 10A.
CVSD INPUT LEVEL vs 2ND AND 3RD HARMONIC DISTORTION
C-MESSAGE WEIGHTED
-10
INPUT
-20 ^{FREQUENCY 1kHz}
-30
32kHz CLOCK
3RD
-40
2ND
-50
-24
-17
-11
-3.8
INPUT SIGNAL LEVEL (dB)
+3.0
CVSD SIGNAL TO 2ND AND 3RD HARMONIC DISTORTION
C-MESSAGE WEIGHTED
-10
-20
V_IN = 0.5V_RMS
32kHz CLOCK
-30
-40
2ND
-50
-60
0
3RD
1000
2000
3000
INPUT FREQUENCY (Hz)
4000
FIGURE 9B.
FIGURE 10B.
CVSD INPUT LEVEL vs 2ND AND 3RD HARMONIC DISTORTION
C-MESSAGE WEIGHTED
-10
INPUT
-20 ^{FREQUENCY 1kHz}
64kHz CLOCK
-30
-40
-50
-24
2ND
-17
-11
-3.8
INPUT SIGNAL LEVEL (dB)
3RD
+3.0
CVSD SIGNAL TO 2ND AND 3RD HARMONIC DISTORTION
C-MESSAGE WEIGHTED
-10
-20
V_IN = 0.5V_RMS
64kHz CLOCK
-30
-40
2ND
-50
-60
0
3RD
1000
2000
3000
INPUT FREQUENCY (Hz)
4000
FIGURE 9C.
FIGURE 10C.
FIGURE 9. CVSD INPUT LEVEL vs 2ND AND 3RD HARMONIC
DISTORTION
FIGURE 10. CVSD INPUT FREQUENCY vs 2ND AND 3RD
HARMONIC DISTORTION
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