HC-55564 Datasheet, PDF (5/9 Pages) Harris Corporation – Continuously Variable Slope Delta-Modulator (CVSD)

HC-55564
Figures 4, 5, and 6 illustrate the typical frequency
response of the HC-55564 for varying input levels and for
varying sampling rates. To prevent slope overload (slew
limiting), the 0dB boundary should not be exceeded. The
frequency response is directly proportional to the sampling
clock rate. The flat bandwidth at 0dB doubles for every
doubling in sampling rate. The output levels were mea-
sured in the encode mode, without filtering, from A_IN to
A_OUT, at V_DD = 5V. 0dB = 1.2V_RMS.
A_OUT
0dB = INPUT SIGNAL LEVEL
A_IN
-6dB
-10
-12dB
-20
-18dB
-24dB
-30
-30dB
-36dB
-40
100
1000
10000
INPUT FREQUENCY AT A_IN (Hz)
FIGURE 4. 16kbps
A_OUT
A_IN
0dB = INPUT SIGNAL LEVEL
-6dB
-12dB
-18dB
-24dB
-30dB
-36dB
100
1000
INPUT FREQUENCY AT A_IN (Hz)
FIGURE 5. 32kbps
-10
-20
-30
-40
10000
A_OUT
A_IN
0dB = INPUT SIGNAL LEVEL
-6dB
-12dB
-18dB
-24dB
-30dB
-36dB
100
1000
INPUT FREQUENCY AT A_IN (Hz)
FIGURE 6. 64kbps
5
-10
-20
-30
-40
10000