Datasheet

AD9278 Data Sheet
Rev. A | Page 4 of 44
Parameter
1
Test Conditions/Comments Min Typ Max Unit
Input-Referred Noise Voltage GAIN+ = 1.6 V, R
FB
= ∞
LNA gain = 15.6 dB 1.7 nV/√Hz
LNA gain = 17.9 dB 1.5 nV/√Hz
LNA gain = 21.3 dB 1.3 nV/√Hz
Noise Figure
GAIN+ = 1.6 V, R
S
= 50 Ω
Active Termination Matched LNA gain = 15.6 dB, R
FB
= 200 Ω 9.2 dB
LNA gain = 17.9 dB, R
FB
= 250 Ω 7.7 dB
LNA gain = 21.3 dB, R
FB
= 350 Ω 6.3 dB
Unterminated LNA gain = 15.6 dB, R
FB
= ∞ 6.7 dB
LNA gain = 17.9 dB, R
FB
= ∞ 5.7 dB
LNA gain = 21.3 dB, R
FB
= ∞ 4.9 dB
Correlated Noise Ratio No signal, correlated/uncorrelated −30 dB
Output Offset −35 +35 LSB
Signal-to-Noise Ratio (SNR) f
IN
= 5 MHz at −10 dBFS, GAIN+ = 0 V, 65 dBFS
f
IN
= 5 MHz at −1 dBFS, GAIN+ = 1.6 V 57 dBFS
Harmonic Distortion
Second Harmonic f
IN
= 5 MHz at −10 dBFS, GAIN+ = 0 V −70 dBc
f
IN
= 5 MHz at −1 dBFS, GAIN+ = 1.6 V −70 dBc
Third Harmonic f
IN
= 5 MHz at −10 dBFS, GAIN+ = 0 V −70 dBc
f
IN
= 5 MHz at −1 dBFS, GAIN+ = 1.6 V −70 dBc
Two-Tone Intermodulation (IMD3) f
RF1
= 5.015 MHz, f
RF2
= 5.020 MHz,
A
RF1
= 0 dB, A
RF2
= −20 dB, GAIN+ =
1.6 VIMD3 relative to A
RF2
−70 dBc
Channel-to-Channel Crosstalk f
IN1
= 5.0 MHz at −1 dBFS −60 dB
Overrange condition
2
−55 dB
Channel-to-Channel Delay
Variation
Full TGC path, f
IN
= 5 MHz, GAIN+ = 0 V to
1.6 V
0.3 Degrees
PGA Gain Differential input to differential output 21/24/27/30 dB
GAIN ACCURACY 25°C
Gain Law Conformance Error 0 < GAIN+ < 0.16 V 0.5 dB
0.16 V < GAIN+ < 1.44 V −1.6 +1.6 dB
1.44 V < GAIN+ < 1.6 V 0.5 dB
Linear Gain Error GAIN+ = 0.8 V, normalized for ideal AAF
loss
−1.6 +1.6 dB
Channel-to-Channel Matching 0.16 V < GAIN+ < 1.44 V 0.1 dB
GAIN CONTROL INTERFACE
Control Range Differential −0.8 +0.8 V
Single-ended 0 1.6 V
Gain Range
GAIN+ = 0 V to 1.6 V
45
dB
Scale Factor 28 dB/V
Response Time 45 dB change 750 ns
Gain+ Impedance Single-ended 10 MΩ
Gain− Impedance Single-ended 70 kΩ
CW DOPPLER MODE
LO Frequency f
LO
= f
4LO
/4 1 10 MHz
Phase Resolution Per channel 22.5 Degrees
Output DC Bias (Single-Ended) CWI+, CWI−, CWQ+, CWQ− 1.5 V
Output AC Current Range Per CWI+, CWI−, CWQ+, CWQ−, each
channel enabled
±1.25 mA
Transconductance (Differential) Demodulated I
OUT
/V
IN
, per CWI+, CWI−,
CWQ+, CWQ−
LNA gain = 15.6 dB 1.8 mA/V
LNA gain = 17.9 dB 2.4 mA/V
LNA gain = 21.3 dB 3.5 mA/V