MC44BC375U Datasheet, PDF (7/16 Pages) Freescale Semiconductor, Inc – PLL Tuned VHF (Channel 3 / 4)Audio / Video Modulator

Table 8. Audio Performance Characteristics
Parameter
Test Conditions⁽¹⁾
Min
Typ
Max
Unit
Type
Picture-to-Sound ratio
PSS pin = High
PSS pin = Low
14
16
18
dB
B
12
14
14
Picture to Sound ratio difference between PSS = HI and PSS = LO
1.5
2.0
2.5
dB
B
Audio modulation depth
Using specific pre-emphasis circuit, Audio input = 1.0 KHz @ 205 mVrms
Fs = 4.5 MHz
(100% modulation = ±25 KHz FM deviation)
75
85
95
%
B
Fs = 5.5 MHz
(100% modulation = ±50 KHz FM deviation)
75
85
95
%
B
Audio input resistance
45
55
61
KΩ
A
Audio Frequency response
Reference 0 dB at 1.0 KHz,
Measure from 50 Hz to 15 KHz
Depends on loop filter components
-2.5
—
+2.0
dB
C
Audio Distortion FM (THD only)
At 1.0 KHz, 100% modulation (±50 KHz) No video
—
0.3
1.0
%
C
Audio S/N with Sync Buzz FM
50
53
—
dB
C
1. See Performance Measurement Test Set-ups, Table 9.
Application Specific Products
Freescale Semiconductor
MC44BC375U
7