* SPICE netlist
V4 Refin 0 {VREF}
C9 0 ADC_out 0.1p
C10 0 ADC_out_dsp 0.1p
V1 VOCM 0 1.5
V2 _DIS 0 3.3
V_FS1 N006 0 {fs}
V_SEL1 N008 0 {sel}
V_DEC1 N007 0 {decimation}
V6 VS+ 0 5
V7 VS- 0 -1
V14 VDD33 0 3.3
V15 CNV 0 PULSE(0 1.1 {ACQ_delay} 0.2n 0.2n {0.9*(1/fs)} {1/fs})
Vin_n N003 Vin_n SINE(0 {input_Vpp/4} {input_freq}) AC 0.5 0
Vin_cm N003 0 {input_cm} AC 0
Vin_p Vin_p N003 SINE(0 {input_Vpp/4} {input_freq}) AC 0.5 0
C1 N001 N002 {Cfb}
C2 N004 N005 {Cfb}
XU1 N001 N002 NC_01 NC_02 Vin_p Vin_n NC_03 NC_04 N004 N005 _DIS CNV ADC_out ADC_out ADC_out_dsp VS+ VS- VOCM Refin VDD33 N006 N008 N007 0 AD4880 ;pnba ))))))))))_DISABLE_FDA)))))))VOCM))))))GND
.param VREF=3
.tran 0 20u 0.1u
.meas NOISE output_noise_rms INTEG V(onoise) FROM 10 TO {Fmax_noise_integration}
.meas NOISE full_scale_sine_rms PARAM 2*VREF/(2*sqrt(2))
.meas NOISE dynamic_range PARAM 20*log10(full_scale_sine_rms/output_noise_rms)
.param Fmax_noise_integration = 1G
.meas NOISE ENOB PARAM (dynamic_range - 1.76)/6.02
.param decimation 4
.meas AC ADC_out_max MAX MAG(V(ADC_out))
.meas AC bw_3db FIND frequency WHEN mag(V(ADC_out))=(ADC_out_max/sqrt(2))
.param sel 3
.param input_Vpp={5/1.03}
.param input_freq = 250k
.param input_cm = 1.5
.param fs = 40MEG
.param ACQ_delay = 0.1u
.param Cfb = 220pF

* LTspice schematic (.asc)
Version 4.1
SHEET 1 3264 2144
WIRE 1360 -1072 1344 -1072
WIRE 1632 -1072 1616 -1072
WIRE 576 -1056 560 -1056
WIRE 800 -1056 784 -1056
WIRE 1008 -1056 992 -1056
WIRE 1344 -1024 1344 -1072
WIRE 1616 -1024 1616 -1072
WIRE 560 -1008 560 -1056
WIRE 784 -1008 784 -1056
WIRE 992 -1008 992 -1056
WIRE 1344 -912 1344 -944
WIRE 1616 -912 1616 -944
WIRE 560 -896 560 -928
WIRE 784 -896 784 -928
WIRE 992 -896 992 -928
WIRE 880 -464 784 -464
WIRE 880 -448 880 -464
WIRE 880 -352 880 -368
WIRE 1504 -320 1296 -320
WIRE 1584 -320 1504 -320
WIRE 1584 -288 1584 -320
WIRE -32 -272 -48 -272
WIRE 96 -272 80 -272
WIRE 784 -272 784 -464
WIRE 1136 -272 1088 -272
WIRE -48 -224 -48 -272
WIRE 80 -224 80 -272
WIRE 784 -224 784 -272
WIRE 1088 -224 1088 -272
WIRE 1584 -176 1584 -208
WIRE -288 -96 -368 -96
WIRE -288 -32 -368 -32
WIRE -1376 48 -1424 48
WIRE -912 48 -1376 48
WIRE -1424 80 -1424 48
WIRE 1504 96 1408 96
WIRE 1600 96 1504 96
WIRE 1504 128 1504 96
WIRE -912 160 -912 48
WIRE -288 160 -912 160
WIRE 1296 160 1296 -320
WIRE 1296 160 1136 160
WIRE -1424 208 -1424 160
WIRE -1424 208 -1632 208
WIRE 1504 224 1504 192
WIRE -1632 240 -1632 208
WIRE -1424 240 -1424 208
WIRE -288 256 -912 256
WIRE 1168 256 1136 256
WIRE 1408 256 1408 96
WIRE 1408 256 1168 256
WIRE 1168 304 1168 256
WIRE 1168 304 1136 304
WIRE 1504 336 1136 336
WIRE 1584 336 1504 336
WIRE -1632 368 -1632 320
WIRE -1424 368 -1424 320
WIRE -1376 368 -1424 368
WIRE -912 368 -912 256
WIRE -912 368 -1376 368
WIRE 1504 368 1504 336
WIRE -288 448 -368 448
WIRE 1504 464 1504 432
WIRE -288 512 -368 512
WIRE -288 576 -336 576
WIRE -288 624 -336 624
WIRE 400 704 400 672
WIRE 784 928 784 672
WIRE 784 928 688 928
WIRE 912 928 912 672
WIRE 1008 928 912 928
WIRE 688 976 688 928
WIRE 848 976 848 672
WIRE 1008 976 1008 928
WIRE 688 1072 688 1056
WIRE 848 1072 848 1056
WIRE 1008 1072 1008 1056
FLAG 880 -352 0
FLAG 1504 224 0
FLAG 1504 464 0
FLAG 1600 96 ADC_out
FLAG 1584 336 ADC_out_dsp
FLAG 1344 -912 0
FLAG 1360 -1072 VOCM
FLAG 1616 -912 0
FLAG 1632 -1072 _DIS
FLAG 688 1072 0
FLAG 848 1072 0
FLAG 1008 1072 0
FLAG 560 -896 0
FLAG 784 -896 0
FLAG 576 -1056 VS+
FLAG 800 -1056 VS-
FLAG 992 -896 0
FLAG 1008 -1056 VDD33
FLAG 1584 -176 0
FLAG 1504 -320 CNV
FLAG 1136 -272 VDD33
FLAG 784 -272 Refin
FLAG -1632 368 0
FLAG -1376 48 Vin_p
FLAG -1376 368 Vin_n
FLAG 400 704 0
FLAG -32 -272 VS+
FLAG 96 -272 VS-
FLAG -336 624 VOCM
FLAG -336 576 _DIS
SYMBOL voltage 880 -464 R0
SYMATTR InstName V4
SYMATTR Value {VREF}
SYMBOL cap 1488 192 M180
SYMATTR InstName C9
SYMATTR Value 0.1p
SYMBOL cap 1488 432 M180
SYMATTR InstName C10
SYMATTR Value 0.1p
SYMBOL voltage 1344 -1040 R0
SYMATTR InstName V1
SYMATTR Value 1.5
SYMBOL voltage 1616 -1040 R0
SYMATTR InstName V2
SYMATTR Value 3.3
SYMBOL voltage 688 960 M0
SYMATTR InstName V_FS1
SYMATTR Value {fs}
SYMBOL voltage 848 960 M0
SYMATTR InstName V_SEL1
SYMATTR Value {sel}
SYMBOL voltage 1008 960 M0
SYMATTR InstName V_DEC1
SYMATTR Value {decimation}
SYMBOL voltage 560 -1024 R0
SYMATTR InstName V6
SYMATTR Value 5
SYMBOL voltage 784 -1024 R0
SYMATTR InstName V7
SYMATTR Value -1
SYMBOL voltage 992 -1024 R0
SYMATTR InstName V14
SYMATTR Value 3.3
SYMBOL voltage 1584 -304 R0
SYMATTR Value PULSE(0 1.1 {ACQ_delay} 0.2n 0.2n {0.9*(1/fs)} {1/fs})
SYMATTR InstName V15
SYMBOL voltage -1424 224 R0
SYMATTR Value2 AC 0.5 0
SYMATTR Value SINE(0 {input_Vpp/4} {input_freq})
SYMATTR InstName Vin_n
SYMBOL voltage -1632 224 R0
SYMATTR Value2 AC 0
SYMATTR InstName Vin_cm
SYMATTR Value {input_cm}
SYMBOL voltage -1424 64 R0
SYMATTR Value2 AC 0.5 0
SYMATTR Value SINE(0 {input_Vpp/4} {input_freq})
SYMATTR InstName Vin_p
SYMBOL cap -384 -96 R0
SYMATTR InstName C1
SYMATTR Value {Cfb}
SYMBOL cap -384 448 R0
SYMATTR InstName C2
SYMATTR Value {Cfb}
SYMBOL AD4880 112 192 R0
SYMATTR InstName U1