Philips Semiconductors
Product specification
TDA4555
TDA4556
Multistandard decoder
PARAMETER
SYMBOL
MIN.
TYP.
MAX. UNIT
Sandcastle pulse detector (see note 5)
Input voltage pulse levels (pin 24)
to separate vertical and horizontal blanking pulses
required pulse amplitude
V24-9
V24-9(p-p)
V24-9
V24-9(p-p)
V24-9
V24-9(p-p)
V24-9
1,2
−
−
−
−
−
−
−
−
2,0
3,0
4,0
5,0
7,7
VP
V
2,0
3,2
4,0
6,5
7,7
−
V
to separate horizontal blanking pulse
required pulse amplitude
V
V
to separate burst gating pulse
required pulse amplitude
V
V
Input voltage during horizontal scanning
Input current
1,0
100
V
−I24
−
µA
Notes
1. Value measured without influence of external circuitry.
2. Relative to phase at V17-9 = 3 V.
3. Or not connected.
4. The signal amplitude of the colour difference signals (R-Y) and (B-Y) is dependent on the characteristics of the
external tuned circuits at pins 7, 8 and 4, 5 respectively. Adjustment of the amplitude is achieved by varying the
Q-factor of these tuned circuits. The resonant frequency must be adjusted such that the demodulated output
frequency (fo) provides the same output level as the internally inserted reference voltage (achromatic value).
5. The sandcastle pulse is compared with three internal threshold levels, which are proportional to the supply voltage.
November 1984
8
NXP [ NXP ]
