* SPICE netlist
XU1 0 N001 V+ v- o2 N005 LT6210 ;pnba In+)In-)V+)V-)OUT)V-1
R1 N005 0 1K
v- v- 0 -15
v+ V+ 0 +15
RF o2 N001 100k
R2 N001 N004 {R}
XU2 0 N003 V+ v- o1 level1 Avol=1Meg GBW=10Meg Vos=0 En=0 Enk=0 In=0 Ink=0 Rin=500Meg ;pnba In+)In-)V+)V-)OUT
V1 N004 0 AC 1
V2 N002 0 AC 1
R3 N003 N002 100
Rf2 o1 N003 {R}
XU3 0 N006 V+ v- o level1 Avol=1Meg GBW=10Meg Vos=0 En=0 Enk=0 In=0 Ink=0 Rin=500Meg ;pnba In+)In-)V+)V-)OUT
V3 N006 0 AC 1
V4 N007 0 1
RLOAD N011 0 300m
RShunt N007 N011 0.1
Rin1 N008 N007 100k
Rin2 N010 N011 100k
XU4 N008 N010 V+ v- N009 level1 Avol=1Meg GBW=10Meg Vos=0 En=0 Enk=0 In=0 Ink=0 Rin=500Meg ;pnba In+)In-)V+)V-)OUT
C1 N008 N010 100n
M1 N008 N009 Out Out BSS145
Rout Out 0 100k
C2 Out 0 1n
.step param R list 100k 10k 1k 100
.ac dec 100 1 10Meg

* LTspice schematic (.asc)
Version 4
SHEET 1 880 672
WIRE -184 -320 -216 -320
WIRE 152 -320 56 -320
WIRE 248 -320 232 -320
WIRE 120 -256 120 -272
WIRE -232 -240 -232 -272
WIRE -392 -224 -424 -224
WIRE -296 -224 -296 -320
WIRE -296 -224 -312 -224
WIRE -264 -224 -296 -224
WIRE -40 -224 -56 -224
WIRE 56 -224 56 -320
WIRE 56 -224 40 -224
WIRE 104 -224 56 -224
WIRE -184 -208 -184 -320
WIRE -184 -208 -200 -208
WIRE -168 -208 -184 -208
WIRE -424 -192 -424 -224
WIRE -264 -192 -280 -192
WIRE 248 -192 248 -320
WIRE 248 -192 200 -192
WIRE 296 -192 248 -192
WIRE -56 -176 -56 -224
WIRE -232 -160 -232 -176
WIRE 104 -160 56 -160
WIRE -280 -144 -280 -192
WIRE 56 -128 56 -160
WIRE -424 -96 -424 -112
WIRE 120 -96 120 -128
WIRE 152 -96 152 -128
WIRE -56 -80 -56 -96
WIRE 376 -64 376 -80
WIRE 344 -48 232 -48
WIRE 440 -32 408 -32
WIRE 232 -16 232 -48
WIRE 344 -16 328 -16
WIRE -328 0 -440 0
WIRE -296 0 -328 0
WIRE -184 0 -216 0
WIRE -104 0 -184 0
WIRE 88 0 -104 0
WIRE 152 0 152 -16
WIRE 328 16 328 -16
WIRE 376 16 376 0
WIRE 88 32 88 0
WIRE -328 64 -328 0
WIRE -184 64 -184 0
WIRE -40 80 -40 48
WIRE 232 80 232 64
WIRE -104 96 -104 0
WIRE -72 96 -104 96
WIRE 40 112 -8 112
WIRE -72 128 -104 128
WIRE -440 176 -440 0
WIRE 88 176 88 128
WIRE 88 176 24 176
WIRE 120 176 88 176
WIRE -328 192 -328 144
WIRE -280 192 -328 192
WIRE -184 192 -184 128
WIRE -184 192 -200 192
WIRE -104 192 -104 128
WIRE -104 192 -184 192
WIRE -40 192 -40 144
WIRE 88 192 88 176
WIRE 24 208 24 176
WIRE -328 240 -328 192
WIRE 248 256 248 240
WIRE 376 256 376 224
WIRE 24 288 24 272
WIRE 88 288 88 272
WIRE -440 304 -440 256
WIRE -328 336 -328 320
FLAG 152 0 0
FLAG 376 336 0
FLAG 248 336 0
FLAG 248 240 V+
FLAG 376 224 v-
FLAG 296 -192 o2
FLAG -232 -160 v-
FLAG 120 -96 v-
FLAG 120 -272 V+
FLAG -232 -272 V+
FLAG -168 -208 o1
FLAG -280 -144 0
FLAG 56 -128 0
FLAG -56 -80 0
FLAG -424 -96 0
FLAG 376 16 v-
FLAG 376 -80 V+
FLAG 440 -32 o
FLAG 232 80 0
FLAG 328 16 0
FLAG -440 304 0
FLAG -328 336 0
FLAG -40 192 V+
FLAG -40 48 v-
FLAG 88 288 0
FLAG 24 288 0
FLAG 120 176 Out
SYMBOL OpAmps\\LT6210 136 -192 R0
SYMATTR InstName U1
SYMBOL res 136 -112 R0
SYMATTR InstName R1
SYMATTR Value 1K
SYMBOL voltage 376 240 R0
SYMATTR InstName v-
SYMATTR Value -15
SYMBOL voltage 248 240 R0
SYMATTR InstName v+
SYMATTR Value +15
SYMBOL res 248 -336 R90
SYMATTR InstName RF
SYMATTR Value 100k
SYMBOL res 56 -240 R90
SYMATTR InstName R2
SYMATTR Value {R}
SYMBOL OpAmps\\UniversalOpAmp1 -232 -208 R0
SYMATTR InstName U2
SYMBOL voltage -56 -192 R0
SYMATTR InstName V1
SYMATTR Value ""
SYMATTR Value2 AC 1
SYMBOL voltage -424 -208 R0
SYMATTR InstName V2
SYMATTR Value ""
SYMATTR Value2 AC 1
SYMBOL res -296 -240 R90
SYMATTR InstName R3
SYMATTR Value 100
SYMBOL res -200 -336 R90
SYMATTR InstName Rf2
SYMATTR Value {R}
SYMBOL OpAmps\\UniversalOpAmp1 376 -32 R0
SYMATTR InstName U3
SYMBOL voltage 232 -32 R0
SYMATTR InstName V3
SYMATTR Value ""
SYMATTR Value2 AC 1
SYMBOL voltage -440 160 R0
SYMATTR InstName V4
SYMATTR Value 1
SYMBOL Misc\\EuropeanResistor -344 224 R0
SYMATTR InstName LOAD
SYMATTR Value 300m
SYMBOL res -344 48 R0
SYMATTR InstName Shunt
SYMATTR Value 0.1
SYMBOL res -200 -16 R90
SYMATTR InstName Rin1
SYMATTR Value 100k
SYMBOL res -184 176 R90
SYMATTR InstName Rin2
SYMATTR Value 100k
SYMBOL OpAmps\\UniversalOpAmp1 -40 112 M180
SYMATTR InstName U4
SYMBOL cap -200 64 R0
SYMATTR InstName C1
SYMATTR Value 100n
SYMBOL nmos 40 32 R0
SYMATTR InstName M1
SYMATTR Value BSS145
SYMBOL res 72 176 R0
SYMATTR InstName Rout
SYMATTR Value 100k
SYMBOL cap 8 208 R0
SYMATTR InstName C2
SYMATTR Value 1n