TLC5733 Datasheet, PDF (7/23 Pages) Texas Instruments – 20 MSPS 3-CHANNEL ANALOG-TO-DIGITAL CONVERTER

TLC5733A
20 MSPS 3ĆCHANNEL ANALOGĆTOĆDIGITAL CONVERTER
WITH HIGHĆPRECISION CLAMP
SLAS104B − JULY 1995 − REVISED FEBRUARY 2001
operating characteristics at QnDV_DD = 2.7 V to 5.25 V, DV_DD = 5 V, V_CC = 5 V, V_ref(RT) = 2.5 V,
V_ref(RB) = 0.5 V, f_(CLK) = 20 MHz, T_A = 25°C (unless otherwise noted)
PARAMETER
EZS Zero-scale error
EFS Full-scale error
EL
Linearity error
ED Linearity error, differential
fc
Maximum conversion rate
BW Analog input bandwidth
tpd Digital output delay time
Differential gain
Differential phase
Aperture jitter time
Sampling delay time
† _{Institute of Radio Engineers}
TEST CONDITIONS
Vref = REFT − REFB = 2 V
Vref = REFT − REFB = 2 V
f(CLK) = 20 MHz,
f(CLK) = 20 MHz,
TA = −20°C to 75°C
f(CLK) = 20 MHz,
f(CLK) = 20 MHz,
TA = −20°C to 75°C
VI = 0.5 V − 2.5 V,
At − 1 dB
VI = 0.5 V to 2.5 V
VI = 0.5 V to 2.5 V
VI = 0.5 V to 2.5 V
VI = 0.5 V to 2.5 V
fI = 1-kHz ramp waveform
CL = 10 pF
NTSC 40 IRE† modulation wave,
NTSC 40 IRE† modulation wave,
fc = 14.3 MSPS
fc = 14.3 MSPS
MIN TYP MAX UNIT
−18 −43 −68 mV
− 20
0
20 mV
± 0.4 ± 0.75
± 0.4
LSB
±1
± 0.3 ± 0.5
LSB
± 0.3 ± 0.75
20
14
18
1%
0.7
30
4
MSPS
MHz
30 ns
deg
ps
ns
detailed description
clamp function
The clamp function is optimized for a YUV video signal and has two clamp modes. The first mode uses the
COMPOSITE SYNC signal as the input to the EXTCLP terminal to generate an internal clamp pulse and the
second mode uses an externally generated clamp pulse as the input to the EXTCLP terminal.
In the first mode, the device detects false pulses in the COMPOSITE SYNC signal by monitoring the rising and
falling edges of the COMPOSITE SYNC signal pulses. This monitoring prevents faulty operation caused by
disturbances and missing pulses of the COMPOSITE SYNC signal input on EXTCLP and external spike noise.
When fault pulses are detected, the device internally generates a train of clamp pulses at the proper positions
(1H) by an internal 910-counter for NTSC and a 1136-counter for PAL. The device checks clamp pulses for 1H
time and generates clamp pulses at correct positions when COMPOSITE SYNC pulses are in error in time.
The internal counter continually produces a horizontal sync period (1H) that is NTSC or PAL compatible as
selected by the condition of the NT/PAL terminal.
clamp voltages and selection
Table 1 shows the clamping level during the clamp interval. Table 2 shows the selection of the internal or external
clamp pulse. With either NTSC or PAL, the internal clamp pulse is always used.
Table 1. Clamp Level (Internal Connection Level)
CHANNEL OF ADC
ADC A • VI(A)
ADC B • VI(B)
ADC C • VI(C)
OUTPUT CODE
00010000
10000000
10000000
APPLICATION
Y
(U, V)
(U, V)
• POST OFFICE BOX 655303 DALLAS, TEXAS 75265
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