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INTEGRATED CIRCUITS
DATA SHEET
TDA8786; TDA8786A 10-bit analog-to-digital interface for CCD cameras
Product specification Supersedes data of 1997 May 20 File under Integrated Circuits, IC02 1997 Nov 17
Philips Semiconductors
Product specification
10-bit analog-to-digital interface for CCD cameras
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. 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 APPLICATIONS
TDA8786; TDA8786A
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.
• CCD camera systems.
MIN. 4.5 4.5 2.5 − − − − − − 18 − − −
TYP. 4.75 4.75 2.6 83 16 1 10 400 6 − 30 0.5 475
MAX. 5.5 5.5 5.5 − − − − 1200 − − − − −
UNIT V V V mA mA mA bits mV dB MHz dB LSB mW
fCLK = 18 MHz; CL = 20 pF; ramp input
gain = 3.5 dB
ORDERING INFORMATION TYPE NUMBER TDA8786G TDA8786AG 1997 Nov 17 PACKAGE NAME LQFP48 DESCRIPTION plastic low profile quad flat package; 48 leads; body 7 × 7 × 1.4 mm 2 VERSION SOT313-2
Philips Semiconductors
Product specification
10-bit analog-to-digital interface for CCD cameras
BLOCK DIAGRAM
TDA8786; TDA8786A
handbook, full pagewidth
VCCA3 IN2 47 IN1 46 AGND3 48 45 CDSP2 44 CDSP1 43 CLPCDS 42 CLK 41
DGND2
VCCD2 39
VCCO OE 38 37
40
36 TRACKAND-HOLD TRACKAND-HOLD TRACKAND-HOLD CLOCK GENERATOR 35
OGND
TRACKAND-HOLD 19 5 CLAMP
TRACKAND-HOLD
D9
34 CLAMP ref2 33
STGE AGND1
D8
D7
TDA8786 TDA8786A
AMPOUT PBK 4 2 10-BIT ADC AGCOUT CLPOPB 7 1 ref1 PBIN VCCA1 PBOUT ADCIN 8 6 4-BIT DAC 9 10 1 OPTICAL BLACK CLAMP 9-BIT DAC 1 SOFT CLIPPER AGC OUTPUTS BUFFER +6 dB
32
D6
31
D5
30
D4
29
D3
28
D2
27
D1
26 25 10-BIT DAC 8-BIT DAC REGULATOR SERIAL INTERFACE 3
D0 DGND1 OFDOUT
CLPADC
11
CLAMP 12 13 14 15
16
17 VRT
18
23
22
21
20
24 VCCD1
MGE361
Vref
VCCA2 DACOUT AGND2
STDBY SEN DEC1
VRB
SDATA SCLK
Fig.1 Block diagram.
1997 Nov 17
3
Philips Semiconductors
Product specification
10-bit analog-to-digital interface for CCD cameras
PINNING SYMBOL CLPOPB PBK OFDOUT AMPOUT AGND1 VCCA1 AGCOUT PBIN PBOUT ADCIN CLPADC Vref DACOUT AGND2 VCCA2 VRB VRT DEC1 STGE SDATA PIN 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 DESCRIPTION
TDA8786; TDA8786A
optical black clamp control pulse input (active HIGH for TDA8786, active LOW for TDA8786A) pre-blanking control pulse input; if PBK is HIGH (LOW) the signal is replaced by the optical black level for TDA8786 (TDA8786A) analog output of the additional 8-bit control DAC (controlled via the serial interface) CDS amplifier output (fixed gain = +6 dB) analog ground 1 analog supply voltage 1 AGC and soft clipper amplifier signal output optical black clamp and pre-blanking block signal input (from AGCOUT via a capacitor) optical black clamp and pre-blanking block signal output ADC analog signal input (from PBOUT or AGCOUT via a capacitor) clamp control input for ADC analog input signal clamp (active HIGH for TDA8786 and active LOW for TDA8786A) ADC input clamp reference voltage (normally connected to pin VRB or DACOUT) DAC output for ADC clamp level analog ground 2 analog supply voltage 2 ADC reference voltage (BOTTOM) code 0 ADC reference voltage (TOP) code 1023 decoupling 1 (decoupled to ground via a capacitor) CDS offset storage serial data input for the 4 control DACs (9-bit DAC for AGC gain, 4-bit DAC for soft clipper; additional 8-bit DAC for OFD output voltage; 1.