TDA3843 Datasheet, PDF (6/10 Pages) NXP Semiconductors – Sound-IF circuit for TV AM-sound standard L and L’

Philips Semiconductors
Sound-IF circuit for TV AM-sound
standard L and L’
Product specification
TDA3843
PARAMETER
CONDITIONS
SYMBOL MIN. TYP. MAX. UNIT
Ripple rejection
AF signal output
IF filter
V_ripple < 200 mV
(peak-to-peak),
50 to 100 Hz,
measured at 70 Hz
αRR = V_ripple
on V_P/V_{ripple on}
V_O
αRR
30
40
−
dB
Proposal for sound carrier
filter for L-standard
Fig.5
Notes to the characteristics
1. Using the power supply voltage range V_P1 = 5 to 8 V, the performance will not essentially change. Using the power
supply voltage range, V_P2 = 12 V, the performance will be comparable with the performance at V_P1 = 5 to 8 V. The
unused power supply pin must not be connected.
2. Start of gain control (low IF input signal) at −3 dB AF signal reduction at pin 6.
3. End of gain control (high IF input signal) at +1 dB AF signal expansion at pin 6.
4. Sound carrier = 32.4 MHz modulated with f = 1 kHz and a modulation depth m = 80%.
IF input signal V_1-16 = 10 mV (RMS value).
5. A maximum value of 100 kHz is guaranteed, but, typically a maximum value of 700 kHz is found.
6. The capacitor at pin 4 may be omitted, but then the S+W/W figure will be degraded by up to 8 dB in the IF voltage
range 1 mV up to 100 mV.
7. If a higher AC output current is required, an external resistor must be connected from the output to ground. This is
to increase the bias current of the emitter follower (note, the maximum allowable DC output current).
March 1991
6