Philips Semiconductors
10-bit analog-to-digital interface for
CCD cameras
Product specification
TDA8786; TDA8786A
FEATURES
• Correlated Double Sampling (CDS), AGC, soft clipper,
pre-blanking, 10-bit ADC and reference regulator
included
• Fully programmable via a 3-wire serial interface
• Sampling frequency up to 18 MHz
• AGC gain from 3.5 to 33.5 dB (in 0.1 dB steps)
• Programmable soft clipper for white compression
(starting at 40% of the input signal)
• Standby mode available for each block for power saving
applications (19 mW)
• 6 dB fixed gain analog output for analog iris control
• 8-bit and 10-bit DAC included for analog settings
• Low power consumption of only 475 mW (typ.)
• 5 V operation and 2.5 to 5 V operation for the digital
outputs
• CDS control pulse: TDA8786 = HIGH;
TDA8786A = LOW
• TTL compatible inputs, TTL and CMOS compatible
outputs.
GENERAL DESCRIPTION
The TDA8786; TDA8786A is a 10-bit analog-to-digital
interface for CCD cameras. The device includes a
correlated double sampling circuit, AGC, a soft clipper
circuit and a low power 10-bit Analog-to-Digital Converter
(ADC) together with its reference voltage regulator.
The AGC and soft clipper circuits are controlled by on-chip
DACs via a serial interface.
A 10-bit DAC controls the ADC input clamp level.
A pre-blanking function is also included.
An additional DAC is provided for additional system
controls; its output voltage range is 1.4 V (p-p) which is
available at pin OFDOUT.
APPLICATIONS
• CCD camera systems.
QUICK REFERENCE DATA
SYMBOL
VCCA
VCCD
VCCO
ICCA
ICCD
ICCO
ADCres
Vi(CDS)(p-p)
GCDS
fCLK(max)
AGCdyn
Ntot(rms)
Ptot
PARAMETER
analog supply voltage
digital supply voltage
digital outputs supply voltage
analog supply current
digital supply current
digital outputs supply current
ADC resolution
CDS input voltage (peak-to-peak value)
CDS output amplifier gain
maximum clock frequency
AGC dynamic range
total noise from CDS input to ADC
output (RMS value)
total power consumption
CONDITIONS
fCLK = 18 MHz;
CL = 20 pF; ramp input
gain = 3.5 dB
MIN.
4.5
4.5
2.5
−
−
−
TYP.
4.75
4.75
2.6
83
16
1
MAX.
5.5
5.5
5.5
−
−
−
UNIT
V
V
V
mA
mA
mA
−
10
−
bits
−
400 1200 mV
−
6
−
dB
18
−
−
MHz
−
30
−
dB
−
0.5 −
LSB
−
475 −
mW
ORDERING INFORMATION
TYPE
NUMBER
TDA8786G
TDA8786AG
NAME
LQFP48
PACKAGE
DESCRIPTION
plastic low profile quad flat package; 48 leads; body 7 × 7 × 1.4 mm
1997 Nov 17
2
VERSION
SOT313-2