Analog Devices AD845SQ-883B, AD845SQ, AD845SCHIPS, AD845KN, AD845JR-16-REEL7 Datasheet

a		Precision, 16 MHz
		CBFET Op Amp
		AD845

FEATURES

Replaces Hybrid Amplifiers in Many Applications

AC PERFORMANCE: Settles to 0.01% in 350 ns 100 V/ms Slew Rate

12.8 MHz min Unity-Gain Bandwidth

1.75 MHz Full-Power Bandwidth at 20 V p-p

DC PERFORMANCE:

0.25 mV max Input Offset Voltage

5 mV/8C max Offset Voltage Drift

0.5 nA Input Bias Current

250 V/mV min Open-Loop Gain

4 mV p-p max Voltage Noise, 0.1 Hz to 10 Hz

94 dB min CMRR

Available in Plastic Mini-DIP, Hermetic Cerdip and SOIC Packages. Also Available in Tape and Reel in Accordance with EIA-481A Standard

PRODUCT DESCRIPTION

The AD845 is a fast, precise, N channel JFET input, monolithic operational amplifier. It is fabricated using Analog Devices’ complementary bipolar (CB) process. Advanced laser-wafer trimming technology enables the very low input offset voltage and offset voltage drift performance to be realized. This precision, when coupled with a slew rate of 100 V/μs, a stable unity-gain bandwidth of 16 MHz, and a settling time of 350 ns 0.01%—while driving a parallel load of 100 pF and 500 Ω— represents a combination of features unmatched by any FET input IC amplifier. The AD845 can easily be used to upgrade many existing designs which use BiFET or FET input hybrid amplifiers and, in some cases, those which use bipolar input op amps.

The AD845 is ideal for use in applications such as active filters, high speed integrators, photo diode preamps, sample-and-hold amplifiers, log amplifiers, and in buffering A/D and D/A converters. The 250 μV max input offset voltage makes offset nulling unnecessary in many applications. The common-mode rejection ratio of 110 dB over a ±10 V input voltage range represents exceptional performance for a JFET input high speed op amp. This, together with a minimum open-loop gain of 250 V/mV ensures that 12-bit performance is achieved, even in unity-gain buffer circuits.

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Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices.

CONNECTION DIAGRAMS

Plastic Mini-DIP (N) Package	16-Pin SOIC
and Cerdip (Q) Package	(R-16) Package

The AD845 conforms to the standard op amp pinout except that offset nulling is to V+. The AD845J and AD845K grade devices are available specified to operate over the commercial 0°C to +70°C temperature range. AD845A and AD845B devices are specified for operation over the –40°C to +85°C industrial temperature range. The AD845S is specified to operate over the full military temperature range of –55°C to +125°C. Both the industrial and military versions are available in 8-pin cerdip packages. The commercial version is available in an 8-pin plastic mini-DIP and 16-pin SOIC; “J” and “S” grade chips are also available.

PRODUCT HIGHLIGHTS

1.The high slew rate, fast settling time, and dc precision of the AD845 make it ideal for high speed applications requiring 12-bit accuracy.

2.The performance of circuits using the LF400, HA2520/2/5, HA2620/2/5, 3550, OPA605, and LH0062 can be upgraded in most cases.

3.The AD845 is unity-gain stable and internally compensated.

4.The AD845 is specified while driving 100 pF/500 Ω loads.

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: [phone] Fax: [phone]

AD845–SPECIFICATIONS (@ +258C and 615 V dc, unless otherwise noted)

Model			AD845J/A			AD845K/B			AD845S
	Conditions	Min	Typ	Max	Min	Typ	Max	Min	Typ	Max	Units
INPUT OFFSET VOLTAGE1
Initial Offset			0.7	1.5		0.1	0.25		0.25	1.0	mV
	TMIN–TMAX			2.5			0.4			2.0	mV
Offset Drift				20		1.5	5.0			10	mV/°C
INPUT BIAS CURRENT2
Initial	VCM = 0 V		0.75	2		0.5	1		0.75	2	nA
	TMIN–TMAX			45/75			18/38			500	nA
INPUT OFFSET CURRENT
Initial	VCM = 0 V		25	300		15	100		25	300	pA
	TMIN–TMAX			3/6.5			1.2/2.6			20	nA
INPUT CHARACTERISTICS
Input Resistance			1011			1011			1011		kW
Input Capacitance			4.0			4.0			4.0		pF
INPUT VOLTAGE RANGE
Differential			±20			± 20			± 20		V
Common Mode		610	+10.5/–13		610	+10.5/–13		610	+10.5/–13		V
Common-Mode Rejection	VCM = ±10 V	86	110		94	113		86	110		dB
INPUT VOLTAGE NOISE	0.1 Hz to 10 Hz		4			4			4		mV p-p
	f = 10 Hz		80			80			80		nV/Ö	Hz
	f = 100 Hz		60			60			60		nV/Ö
												Hz
	f = 1 kHz		25			25			25		nV/Ö	Hz
	f = 10 kHz		18			18			18		nV/Ö
												Hz
	f = 100 kHz		12			12			12		nV/Ö
												Hz
INPUT CURRENT NOISE	f = 1 kHz		0.1			0.1			0.1		pA/Ö
												Hz
OPEN-LOOP GAIN	VO = ± 10 V
	RLOAD ³ 2 kW	200	500		250	500		200	500		V/mV
	RLOAD ³ 500 W	100	250		125	250		100	250		V/mV
	TMIN–TMAX	70			75			50			V/mV
OUTPUT CHARACTERISTICS
Voltage	RLOAD ³ 500 W	612.5			612.5			612.5			V
Current	Short Circuit		50			50			50		mA
Output Resistance	Open Loop		5			5			5		W
FREQUENCY RESPONSE
Small Signal	Unity Gain	12.8	16		13.6	16		13.6	16		MHz
Full Power Bandwidth3	VO = ± 10 V
	RLOAD = 500 W		1.75			1.75			1.75		MHz
Rise Time			20			20			20		ns
Overshoot			20			20			20		%
Slew Rate		80	100		94	100		94	100		V/ms
Settling Time	10 V Step
	CLOAD = 100 pF
	RLOAD = 500 W
	to 0.01%		350			350	500		350	500	ns
	to 0.1%		250			250			250		ns
DIFFERENTIAL GAIN	f = 4.4 MHz		0.04			0.04			0.04		%
DIFFERENTIAL PHASE	f = 4.4 MHz		0.02			0.02			0.02		Degree
POWER SUPPLY
Rated Performance			±15			± 15			± 15		V
Operating Range	VS = ±5 to ± 15 V	64.75		618	64.75		618	64.75		618	V
Rejection Ratio		88	110		95	113		88	110		dB
Quiescent Current	TMIN to TMAX		10	12		10	12		10	12	mA

NOTES

1Input offset voltage specifications are guaranteed after 5 minutes of operation at T A = +25°C.

2Bias current specifications are guaranteed maximum at either input after 5 minutes of operation at T A = +25°C. 3FPBW = slew rate/2 π V peak.

4“S” grade TMIN–TMAX are tested with automatic test equipment at TA = –55°C and TA = +125°C.

All min and max specifications are guaranteed. Specifications shown in boldface are tested on all production units at final electrical test. Results from these tests are used to calculate outgoing quality levels.

Specifications subject to change without notice.

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AD845

ABSOLUTE MAXIMUM RATINGS1

Supply Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±18 V Internal Power Dissipation2

Plastic Mini-DIP . . . . . . . . . . . . . . . . . . . . . . . . . . 1.6 Watts Cerdip . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.4 Watts 16-Pin SOIC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.5 Watts

Input Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . + VS Output Short-Circuit Duration . . . . . . . . . . . . . . . . Indefinite

Differential Input Voltage . . . . . . . . . . . . . . . . . . +VS and –VS Storage Temperature Range

Q . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .–65°C to +150°C N, R . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .–65°C to +125°C Lead Temperature Range (Soldering 60 sec) . . . . . . . . +300°C

NOTES

1Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress rating only, and functional operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability .

2Mini-DIP package: θJA = 100°C/watt; cerdip package: θJA = 110°C/watt. SOIC package: θJA = 100°C/W.

METALIZATION PHOTOGRAPH

Dimensions shown in inches and (mm). Contact factory for latest dimensions.

SUBSTRATE CONNECTED TO +VS

ORDERING GUIDE

	Temperature	Package	Package
Model	Range	Description	Option*
AD845JN	0°C to +70°C	8-Pin Plastic Mini-DIP	N-8
AD845KN	0°C to +70°C	8-Pin Plastic Mini-DIP	N-8
AD845JR-16	0°C to +70°C	16-Pin SOIC	R-16
AD845AQ	–40°C to +85°C	8-Pin Cerdip	Q-8
AD845BQ	–40°C to +85°C	8-Pin Cerdip	Q-8
AD845SQ	–55°C to +125°C	8-Pin Cerdip	Q-8
AD845SQ/883B	–55°C to +125°C	8-Pin Cerdip	Q-8
5962-8964501PA	–55°C to +125°C	8-Pin Cerdip	Q-8
AD845JCHIPS	0°C to +70°C	Die
AD845SCHIPS	–55°C to +125°C	Die
AD845JR-16-REEL	0°C to +70°C	Tape & Reel
AD845JR-16-REEL7	0°C to +70°C	Tape & Reel

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