CA3140E

Single MOSFET-Input Op-Amp DIP-8.2 circuits use this part.

Datasheet · from renesas.com

Substitutes same socket

Parts that fit the same socket: the same function, pin count and pinout. The figures are read off each part's datasheet (this one's from page 3), typical where the sheet gives a typical value, otherwise the maximum. Closest first; the last column says what differs. A different part can change the sound, and a circuit may lean on one particular figure, so read the build document's notes before you swap.

This part

Part	Input	Supply	GBW	Slew	Noise	Iq	Boards
CA3140	mosfet	4–36 V	4.5 MHz	9 V/µs	40 nV	4 mA	12

MOSFET input that reaches 0.5 V below the negative rail, internally compensated; draws about 4 mA.

Fits the same socket

Part	Input	Supply	GBW	Slew	Noise	Iq	Boards	Differs
CA3130	mosfet, RR out	5–16 V	4 MHz	10 V/µs		10 mA	54	needs a compensation capacitor across pins 1 and 8; 16 V max, not for 18 V; rail-to-rail output. Needs a 47 pF capacitor between pins 1 and 8 for unity-gain stability (15 MHz uncompensated) and is limited to 16 V total supply.
LF356	JFET	?–36 V	5 MHz	12 V/µs	12 nV	5 mA	14	JFET input. JFET single drawing about 5 mA; specified at ±15 V.
TL071	JFET	4.5–40 V	5.25 MHz	20 V/µs	37 nV	1.4 mA	178	JFET input. JFET input; this revision shows pins 1, 5 and 8 as no-connect on the DIP, so no offset trim.
TL081	JFET	4.5–40 V	5.25 MHz	20 V/µs	37 nV	1.4 mA	20	JFET input. JFET input; this revision shows no offset-null pins on the DIP.
TL051	JFET	10–30 V	4.5 MHz	17.8 V/µs	10.8 nV	2.1 mA	8	JFET input; rated from 10 V. Trimmed-offset upgrade for the TL071/TL081; pins 1, 5 and 8 are no-connect in this revision.
LF355	JFET	?–36 V	2.5 MHz	5 V/µs	20 nV	2 mA	1	JFET input. Lower-power, slower sibling of the LF356.
OPA134	JFET	5–36 V	8 MHz	20 V/µs	8 nV	4 mA	3	JFET input. FET-input audio op-amp with no offset null; leave pins 1, 5 and 8 unconnected.
LM308	bipolar	10–36 V				0.3 mA	96	bipolar input; needs a compensation capacitor across pins 1 and 8; rated from 10 V. Needs a compensation capacitor (30 pF typical) between pins 1 and 8; the cap sets slew rate and tone.
OPA604AP	JFET	9–48 V	20 MHz	25 V/µs	11 nV	5.3 mA	4	JFET input; much faster, may oscillate in a slow part's place. FET-input audio op-amp that runs to ±24 V but draws about 5.3 mA.
TL061	JFET	10–30 V	1 MHz	3.5 V/µs	30 nV	0.2 mA	34	JFET input; rated from 10 V. Low-power JFET op-amp at 200 µA; the pin table gives offset null on 1 and 5 though the drawing marks them NC.

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