Datasheet

AD9979
Rev. C | Page 6 of 56
ANALOG SPECIFICATIONS
AVDD = 1.8 V, f
CLI
= 65 MHz, typical timing specifications, t
MIN
to t
MAX
, unless otherwise noted.
Table 4.
Parameter Min Typ Max Unit Test Conditions/Comments
CDS
1
Allowable CCD Reset Transient 0.5 0.8 V
CDS Gain Accuracy
−3.0 dB CDS Gain –3.7 –3.2 –2.7 dB
0 dB CDS Gain (Default) –0.9 –0.4 +0.1 dB
+3 dB CDS Gain +1.9 +2.4 +2.9 dB
+6 dB CDS Gain +4.3 +4.8 +5.3 dB
Maximum Input Voltage VGA gain = 6.3 dB, Code 15 (default value)
−3 dB CDS Gain 1.4 V p-p
0 dB CDS Gain (Default) 1.0 V p-p
+3 dB CDS Gain 0.7 V p-p
+6 dB CDS Gain 0.5 V p-p
Allowable Optical Black Pixel Amplitude
0 dB CDS Gain (Default) –100 +200 mV
+6 dB CDS Gain –50 +100 mV
VARIABLE GAIN AMPLIFIER (VGA)
Gain Control Resolution 1024 Steps
Gain Monotonicity Guaranteed
Low Gain Setting 6 dB VGA Code 15 (default)
Maximum Gain Setting 42 dB VGA Code 1023
BLACK LEVEL CLAMP
Clamp Level Resolution 1024 Steps
Minimum Clamp Level (Code 0) 0 LSB Measured at ADC output
Maximum Clamp Level (Code 1023) 1023 LSB Measured at ADC output
ANALOG-TO-DIGITAL CONVERTER (ADC)
Resolution 14 Bits
Differential Nonlinearity (DNL) –1.0 ± 0.5 +1.2 LSB
No Missing Codes Guaranteed
Integral Nonlinearity (INL) 5 16 LSB
Full-Scale Input Voltage 2.0 V
VOLTAGE REFERENCE
Reference Top Voltage (REFT) 1.4 V
Reference Bottom Voltage (REFB) 0.4 V
SYSTEM PERFORMANCE Specifications include entire signal chain
VGA Gain Accuracy 0 dB CDS gain (default)
Low Gain (Code 15) 5.1 5.6 6.1 dB Gain = (0.0359 × code) + 5.1 dB
Maximum Gain (Code 1023) 41.3 41.8 42.3 dB
Peak Nonlinearity, 500 mV Input Signal 0.1 0.4 % 12 dB total gain applied
Total Output Noise 2 LSB rms AC grounded input, 6 dB gain applied
Power Supply Rejection (PSR) 45 dB Measured with step change on supply
1
Input signal characteristics are defined as shown in Figure 2.
200mV MAX
OPTICAL BLACK PIXEL
MINIMUM INPUT LIMIT
(AVSS – 0.3V)
MAXIMUM INPUT LIMIT =
LESSER OF 2.2V
OR (AVDD + 0.3V)
+1.8V TYP (AVDD)
0V (AVSS)
+1.3V TYP (AVDD – 0.5V)
DC RESTORE VOLTAGE
500mV TYP
RESET TRANSIENT
800mV
MAXIMUM
1V MAXIMUM INPUT
SIGNAL RANGE
(0dB CDS GAIN)
05957-002
Figure 2. Input Signal Characteristics