Burr Brown Corporation ADS7817PB, ADS7817P, ADS7817EC-2K5, ADS7817EC-250, ADS7817EC Datasheet

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				ADS7817
			ADS7817	OPA658

For most current data sheet and other product information, visit www.burr-brown.com

ADS7817

12-Bit Differential Input Micro Power Sampling

ANALOG-TO-DIGITAL CONVERTER

FEATURES

●BIPOLAR INPUT RANGE

●TRUE DIFFERENTIAL INPUT

●200kHz SAMPLING RATE

●MICRO POWER: 2.3mW at 200kHz

●POWER DOWN: 3μA Max

●AVAILABLE IN MSOP-8 PACKAGE

●SERIAL INTERFACE

●AC COMMON-MODE REJECTION

APPLICATIONS

●TRANSDUCER INTERFACE

●BATTERY OPERATED SYSTEMS

●REMOTE DATA ACQUISITION

●ISOLATED DATA ACQUISITION

●AC MOTOR CONTROL

DESCRIPTION

The ADS7817 is a 12-bit, 200kHz sampling analog- to-digital converter (A/D) that features a high impedance fully differential analog input. The reference voltage can be varied from 100mV to 2.5V, with a corresponding input-referred resolution between 49μV and 1.22mV.

The differential input, low power, automatic power down, and small size make the ADS7817 ideal for direct connection to transducers in battery operated systems, remote data acquisition, or multi-channel applications. The ADS7817 is available in a plastic mini-DIP-8, an SOIC-8, or an MSOP-8 package.

SAR	Control
VREF
+In		DOUT
CDAC	Serial
–In	Interface	DCLOCK
S/H Amp	Comparator	CS/SHDN

International Airport Industrial Park • Mailing Address: PO Box 11400, Tucson, AZ 85734 • Street Address: 6730 S. Tucson Blvd., Tucson, AZ 85706 • Tel: [phone]

Twx: 910-952-1111 • Internet: http://www.burr-brown.com/ • Cable: BBRCORP • Telex: 066-6491 • FAX: [phone] •mmediateI			Product Info: [phone]
© 1997 Burr-	Brown Corporation	PDS-1369B	Printed in U.S.A., May, 2000

SPECIFICATIONS

At –40°C to +85°C, +VCC = +5V, VREF = +2.5V, fSAMPLE = 200kHz, fCLK = 16 • fSAMPLE, –In = +2.5V, unless otherwise specified.

ADS7817

ADS7817B

ADS7817C

PARAMETER

CONDITIONS

MIN

TYP

MAX

MIN

TYP

MAX

MIN

TYP

MAX

UNITS

ANALOG INPUT

Full-Scale Input Span

+In – (–In)

–VREF

+VREF

V

Absolute Input Voltage

+In

–0.3

VCC +0.3

V

–In

–0.3

4

V

Capacitance

15

pF

Leakage Current

±1

μA

SYSTEM PERFORMANCE

Resolution

12

Bits

No Missing Codes

11

±1

±2

12

±0.8

±2

±0.5

±1

Bits

Integral Linearity Error

LSB(1)

Differential Linearity Error

±1

±2

±0.7

±1

±0.4

±1

LSB

Offset Error

±1

±6

LSB

Gain Error

±0.5

±4

LSB

Noise

63

μVrms

Common-Mode Rejection

80

dB

Power Supply Rejection

82

dB

SAMPLING DYNAMICS

Conversion Time

12

Clk Cycles

Acquisition Time

1.5

Clk Cycles

Throughput Rate

200

kHz

DYNAMIC CHARACTERISTICS

Total Harmonic Distortion

VIN = 5.0Vp-p at 1kHz

–83

dB

VIN = 5.0Vp-p at 5kHz

–81

dB

SINAD

VIN = 5.0Vp-p at 1kHz

71

dB

Spurious Free Dynamic Range

VIN = 5.0Vp-p at 1kHz

86

dB

REFERENCE INPUT

Voltage Range

0.1

2.5

V

Resistance

5

GΩ

CS

= VCC

5

GΩ

CS

= GND, fSAMPLE = 0Hz

Current Drain

At Code FF8h

20

100

μA

fSAMPLE = 12.5kHz

1.3

20

μA

CS = VCC

0.001

3

μA

DIGITAL INPUT/OUTPUT

Logic Family

CMOS

Logic Levels:

IIH = +5μA

VIH

3

+VCC +0.3

V

VIL

IIL = +5μA

–0.3

0.8

V

VOH

IOH = –250μA

3.5

V

VOL

IOL = 250μA

0.4

V

Data Format

Binary

Two’s Complement

POWER SUPPLY REQUIREMENTS

VCC

Specified Performance

4.75

5.25

V

Quiescent Current

460

800

μA

fSAMPLE = 12.5kHz(2, 3)

40

μA

fSAMPLE = 12.5kHz(3)

330

μA

Power Down

3

μA

CS

=VCC, fSAMPLE = 0Hz

TEMPERATURE RANGE

°C

Specified Performance

–40

+85

Specifications same as ADS7817.

NOTE: (1) LSB means Least Significant Bit, with VREF equal to +2.5V, one LSB is 1.22mV. (2) fCLK = 3.2MHz, CS = VCC for 241 clock cycles out of every 256.

(3) See the Power Dissipation section for more information regarding lower sample rates.

The information provided herein is believed to be reliable; however, BURR-BROWN assumes no responsibility for inaccuracies or omissions. BURR-BROWN assumes no responsibility for the use of this information, and all use of such information shall be entirely at the user’s own risk. Prices and specifications are subject to change without notice. No patent rights or licenses to any of the circuits described herein are implied or granted to any third party. BURR-BROWN does not authorize or warrant any BURR-BROWN product for use in life support devices and/or systems.

®

	ADS7817	2

ABSOLUTE MAXIMUM RATINGS(1)

+VCC .....................................................................................................	+6V
Analog Input ...........................................................	–0.3V to (+VCC + 0.3V)
Logic Input .............................................................	–0.3V to (+VCC + 0.3V)
Case Temperature .........................................................................	+100°C
Junction Temperature ....................................................................	+150°C
Storage Temperature .....................................................................	+125°C
External Reference Voltage ..............................................................	+5.5V

NOTE: (1) Stresses above these ratings may permanently damage the device.

PIN CONFIGURATION

VREF				+VCC
	1		8
				DCLOCK
+In	2	ADS7817	7
				DOUT
–In	3		6
GND	4		5		CS/SHDN

PDIP-8,

SOIC-8,

MSOP-8

ELECTROSTATIC DISCHARGE SENSITIVITY

Electrostatic discharge can cause damage ranging from performance degradation to complete device failure. BurrBrown Corporation recommends that all integrated circuits be handled and stored using appropriate ESD protection methods.

ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more susceptible to damage because very small parametric changes could cause the device not to meet published specifications.

PIN ASSIGNMENTS

PIN		NAME		DESCRIPTION
1		VREF		Reference Input.
2			+In	Non Inverting Input.
3			–In	Inverting Input.
4		GND		Ground.
5	CS/SHDN			Chip Select when LOW, Shutdown Mode when HIGH.
6		DOUT		The serial output data word is comprised of 12 bits of data. In operation the data is valid on the falling edge of DCLOCK. The
				second clock pulse after the falling edge of	CS	enables the serial output. After one null bit the data is valid for the next 12 edges.
7		DCLOCK		Data Clock synchronizes the serial data transfer and determines conversion speed.
8		+VCC		Power Supply.

PACKAGE/ORDERING INFORMATION

	MAXIMUM	MAXIMUM
	INTEGRAL	DIFFERENTIAL
	LINEARITY	LINEARITY		PACKAGE	SPECIFICATION
	ERROR	ERROR		DRAWING	TEMPERATURE	PACKAGE	ORDERING	TRANSPORT
PRODUCT	(LSB)	(LSB)	PACKAGE	NUMBER(1)	RANGE	MARKING(2)	NUMBER(3)	MEDIA
ADS7817P	±2	±2	MSOP-8	006	–40°C to +85°C	ADS7817P	ADS7817P	Rails
ADS7817U	±2	±2	MSOP-8	182	–40°C to +85°C	ADS7817U	ADS7817U	"
ADS7817U	"	"	"	"	"	"	ADS7817U/2K5	Tape and Reel
ADS7817E	±2	±2	MSOP-8	337	–40°C to +85°C	A17	ADS7817E	Rails
ADS7817E	"	"	"	"	"	"	ADS7817E/250	Tape and Reel
ADS7817E	"	"	"	"	"	"	ADS7817E/2K5	"
ADS7817PB	±2	±1	Plastic DIP-8	006	–40°C to +85°C	ADS7817PB	ADS7817PB	Rails
ADS7817UB	±2	±1	Plastic DIP-8	182	–40°C to +85°C	ADS7817UB	ADS7817UB	"
ADS7817UB	"	"	"	"	"	"	ADS7817UB/2K5	Tape and Reel
ADS7817EB	±2	±1	SOIC-8	337	–40°C to +85°C	A17	ADS7817EB	Rails
ADS7817EB	"	"	"	"	"	"	ADS7817EB/250	Tape and Reel
ADS7817EB	"	"	"	"	"	"	ADS7817EB/2K5	"
ADS7817PC	±1	±0.75	SOIC-8	006	–40°C to +85°C	ADS7817PC	ADS7817PC	Rails
ADS7817UC	±1	±0.75	SOIC-8	182	–40°C to +85°C	ADS7817UC	ADS7817UC	"
ADS7817UC	"	"	"	"	"	"	ADS7817UC/2K5	Tape and Reel
ADS7817EC	±1	±0.75	SOIC-8	337	–40°C to +85°C	A17	ADS7817EC	Rails
ADS7817EC	"	"	"	"	"	"	ADS7817EC/250	Tape and Reel
ADS7817EC	"	"	"	"	"	"	ADS7817EC/2K5	"

NOTE: (1) For detail drawing and dimension table, please see end of data sheet or Package Drawing File on Web. (2) Performance Grade information is marked on the reel. (3) Models with a slash(/) are available only in Tape and reel in quantities indicated (e.g. /250 indicates 250 units per reel, /2K5 indicates 2500 devices per reel). Ordering 2500 pieces of ”ADS7817E/2K5“ will get a single 2500-piece Tape and Reel. For detailed Tape and Reel mechanical information, refer to the www.burr-brown.com web site under Applications and Tape and Reel Orientation and Dimensions.

®

3	ADS7817

TYPICAL PERFORMANCE CURVES

At TA = +25°C, VCC = +5V, VREF = +2.5V, fSAMPLE = 200kHz, and fCLK = 16 • fSAMPLE, –In = +2.5V, unless otherwise specified.

CHANGE IN OFFSET vs REFERENCE VOLTAGE

		5
		4.5
	(LSB)	4
		3.5
	Offset
		2.5
		3
	in	2
	Change
		1.5
		1
		0.5
		0

1.0	1.25	1.5	1.75	2.0	2.25	2.5
		Reference Voltage (V)

CHANGE IN GAIN vs REFERENCE VOLTAGE

		4
		3.5
	(LSB)	3
		2.5
	Gain
		2
	in
		1
	Change
		1.5

0.5

0

1.0	1.25	1.5	1.75	2.0	2.25	2.5
		Reference Voltage (V)

EFFECTIVE NUMBER OF BITS vs REFERENCE VOLTAGE

	12.0
of Bits	11.5
	11.0
Number	10.5
Effective	10.0
	9.5
	9.0

0.1

1

10

Reference Voltage

CHANGE IN OFFSET vs TEMPERATURE

		1.2
		0.8
	(LSB)	0.4
	25°C	0.0
	from
		–0.4
	Delta
		–0.8
		–1.2

–50	–25	0	25	50	75	100
			Temperature (°C)

CHANGE IN GAIN vs TEMPERATURE

	0.15
(LSB)	0.1
	0.05
25°C	0
from
	–0.05
Delta
	–0.1
	–0.15
	–50		–25		0		25		50		75		100
							Temperature (°C)

PEAK-TO-PEAK NOISE vs REFERENCE VOLTAGE

		18
	(LSB)	15
		12
	Noise
		9
	-to-Peak
		6
	Peak	3
		0

0.1

1

10

Reference Voltage

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	ADS7817	4

TYPICAL PERFORMANCE CURVES (Cont.)

At TA = +25°C, VCC = +5V, VREF = +2.5V, fSAMPLE = 200kHz, and fCLK = 16 • fSAMPLE, –In = +2.5V, unless otherwise specified.

POWER SUPPLY REJECTION vs RIPPLE FREQUENCY

		0
	(dB)	–10
		–20
	Rejection	–30
	Supply	–40
		–50
	Power	–60
		–70
		–80
		–90

1	10	100	1000	10000
		Ripple Frequency (kHz)

SIGNAL-TO-NOISE RATIO AND SIGNAL-TO-(NOISE+DISTORTION) vs INPUT FREQUENCY

	73
	72	SNR
(dB)
	71
SINAD
	70
and		SINAD
	69
SNR
	68
	67
	1	10	100

Input Frequency (kHz)

SIGNAL-TO-(NOISE+DISTORTION) vs INPUT LEVEL

	80
	70
	60
(dB)	50
SINAD	40
	30
	20
	10

–60

–50

–40

–30

–20

–10

0

Input Level (dB)

FREQUENCY SPECTRUM (4096 Point FFT; fIN = 9.9kHz, –0.5dB)

	0
	–20
(dB)	–40
Amplitude	–60
	–80
	–100
	–120
	0	25	50	75	100

Frequency (kHz)

SPURIOUS FREE DYNAMIC RANGE AND TOTAL HARMONIC DISTORTION

vs INPUT FREQUENCY

95		–95
90		–90
		SFDR
85		–85
80		–80	THD (dB)
SFDR(dB)		–75
75
		THD
70		–70
65		–65
1	10	100

Input Frequency (kHz)

CHANGE IN INTEGRAL LINEARITY and DIFFERENTIAL

LINEARITY vs SAMPLE RATE

	1.5
(LSB)	1.0
= 200kHz				Change in Integral
				Linearity (LSB)
	0.5
SAMPLE
from f	0			Change in Differential
Delta
					Linearity (LSB)
	–0.5
	0	80	160	240	320	400

Sample Rate (kHz)

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5	ADS7817