BURR-BROWN ADS803 User Manual

SBAS074B – JANUARY 1997 – REVISED SEPTEMBER 2002

A

D

S

8

0

3

E

12-Bit, 5MHz Sampling

ANALOG-TO-DIGITAL CONVERTER

ADS803

FEATURES

● HIGH SFDR: 82dB at NYQUIST

● HIGH SNR: 69dB

● LOW POWER: 115mW

● LOW DLE: 0.25LSB

● FLEXIBLE INPUT RANGE

● OVER-RANGE INDICATOR

DESCRIPTION

The ADS803 is a high-speed, high dynamic range, 12-bit
pipelined Analog-to-Digital (A/D) converter. This converter
includes a high-bandwidth track-and-hold that gives excel­lent spurious performance up to and beyond the Nyquist rate.
This high-bandwidth, linear track-and-hold minimizes har­monics and has low jitter, leading to excellent SNR perfor­mance. The ADS803 is also pin-compatible with the 10MHz
ADS804 and the 20MHz ADS805.

The ADS803 provides an internal reference and can be
programmed for a 2Vp-p input range for the best spurious
performance and ease of driving. Alternatively, the 5Vp-p input
range can be used for the lowest input referred noise of

+V

S

APPLICATIONS

● IF AND BASEBAND DIGITIZATION

● CCD IMAGING SCANNERS

● TEST INSTRUMENTATION

0.09LSBs rms giving superior imaging performance. There is
also a capability to set the input range in between the 2Vp-p
and 5Vp-p input ranges or to use an external reference. The
ADS803 also provides an over-range indicator flag to indicate
an input range that exceeds the full-scale input range of the
converter. This flag can be used to reduce the gain of the front­end gain-ranging circuitry.

The ADS803 employs digital error-correction techniques to
provide excellent differential linearity for demanding imaging
applications. Its low distortion and high SNR give the extra
margin needed for communications, medical imaging, video,
and test instrumentation applications. The ADS803 is avail­able in an SSOP-28 package.

CLK

VDRV

ADS803

Timing Circuitry

IN

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.

INV

T & H

IN

CM

REFT

12-Bit

Pipelined

ADC

Reference Ladder

and Driver

Reference and

Mode Select

REF

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SEL REFBV

Error

Correction

Logic

3-State

Outputs

OE

Copyright © 1997, Texas Instruments Incorporated

D0

D11

•

•

•

OVR

ABSOLUTE MAXIMUM RATINGS

+VS....................................................................................................... +6V

Analog Input........................................................... (–0.3V) to (+V

Logic Input ............................................................. (–0.3V) to (+V

Case Temperature ......................................................................... +100°C

Junction Temperature .................................................................... +150°C

Storage Temperature..................................................................... +150°C

NOTE: (1) Stresses above those listed under “Absolute Maximum Ratings”
may cause permanent damage to the device. Exposure to absolute maximum
conditions for extended periods may affect device reliability.

(1)

+0.3V)

S

+0.3V)

S

This integrated circuit can be damaged by ESD. Texas Instru-

ELECTROSTATIC
DISCHARGE SENSITIVITY

ments recommends that all integrated circuits be handled with
appropriate precautions. Failure to observe proper handling
and installation procedures can cause damage.

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 its
published specifications.

PACKAGE/ORDERING INFORMATION

PRODUCT PACKAGE-LEAD DESIGNATOR

PACKAGE TEMPERATURE PACKAGE ORDERING TRANSPORT

ADS803E SSOP-28 DB –40°C to +85°C ADS803E ADS803E Rails, 48

(1)

SPECIFIED

RANGE MARKING NUMBER MEDIA, QUANTITY

" """"ADS803E/1K Tape and Reel, 1000

NOTE: (1) For the most current specifications and package information, refer to our web site at www.ti.com.

ELECTRICAL CHARACTERISTICS

At TA = full specified temperature range, VS = +5V, specified input range = 1.5V to 3.5V, single-ended input and sampling rate = 5MHz, unless otherwise specified.

ADS803E

PARAMETER CONDITIONS MIN TYP MAX UNITS
RESOLUTION 12 Tested Bits

SPECIFIED TEMPERATURE RANGE –40 +85 °C
CONVERSION CHARACTERISTICS

Sample Rate 10k 5M Samples/s
Data Latency 6 Clk Cycles

ANALOG INPUT

Single-Ended Input Range 1.5 3.5 V
Standard Optional Single-Ended Input Range 0 5 V
Common-Mode Voltage 2.5 V
Standard Optional Common-Mode Voltage 1V
Input Capacitance 20 pF
Track-Mode Input Bandwidth –3dBFS Input 270 MHz

DYNAMIC CHARACTERISTICS

Differential Linearity Error (Largest Code Error)

f = 500kHz ±0.25 ±0.75 LSB
No Missing Codes Tested
Spurious-Free Dynamic Range

f = 2.48MHz (–1dB input) 74 82 dBFS
2-Tone Intermodulation Distortion

f = 1.8M and 1.9M (–7dBFS each tone)
Signal-to-Noise Ratio (SNR)

f = 2.48MHz (–1dB input) 66.5 69 dB
Signal-to-(Noise + Distortion) (SINAD)

f = 2.48MHz (–1dB input) 65 68 dB
Effective Number of Bits at 2.48MHz
Input Referred Noise 0V to 5V Input 0.09 LSBs rms

Integral Nonlinearity Error

f = 500kHz ±1 ±2 LSB
Aperture Delay Time 1ns
Aperture Jitter 4 ps rms
Over-Voltage Recovery Time 1.5 • FS Input 2 ns
Full-Scale Step Acquisition Time 50 ns

(1)

(3)

(4)

1.5V to 3.5V Input 0.23 LSBs rms

74 dBc

11 Bits

(2)

2

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ADS803

SBAS074B

ELECTRICAL CHARACTERISTICS (Cont.)

At TA = full specified temperature range, VS = +5V, specified input range = 1.5V to 3.5V, single-ended input and sampling rate = 5MHz, unless otherwise specified.

ADS803E

PARAMETER CONDITIONS MIN TYP MAX UNITS
DIGITAL INPUTS

Logic Family CMOS Compatible
Convert Command Start Conversion Rising Edge of Convert Clock
High Level Input Current (V
Low Level Input Current (V
High Level Input Voltage +3.5 V
Low Level Input Voltage +1.0 V
Input Capacitance 5pF

DIGITAL OUTPUTS

Logic Family CMOS/TTL Compatible V
Logic Coding Straight Offset Binary
Low Output Voltage (I
Low Output Voltage (I
High Output Voltage (I
High Output Voltage (I
3-State Enable Time

3-State Disable Time
Output Capacitance 5pF

ACCURACY (5Vp-p Input Range) f
Zero Error (Referred to –FS) At 25°C 0.2 ±1.5 %FS
Zero Error Drift (Referred to –FS) ±5 ppm/°C
Gain Error
Gain Error Drift
Gain Error
Gain Error Drift

(6)

(6)

(7)

(7)

Power-Supply Rejection of Gain ∆V
Reference Input Resistance 1.6 kΩ
Internal Voltage Reference Tolerance (V
Internal Voltage Reference Tolerance (V

POWER-SUPPLY REQUIREMENTS

Supply Voltage: +V
Supply Current: +I
Power Dissipation Operating 115 135 mW
Thermal Resistance,

SSOP-28 50 °C/W

S

S

θ

JA

NOTES: (1) Spurious-Free Dynamic Range refers to the magnitude of the largest harmonic. (2) dBFS means dB relative to full-scale. (3) 2-tone intermodulation
distortion is referred to the largest fundamental tone. This number will be 6dB higher if it is referred to the magnitude of the 2-tone fundamental envelope. (4) Effective
number of bits (ENOB) is defined by (SINAD – 1.76)/6.02. (5) Internal 50kΩ pull-down resistor. (6) Includes internal reference. (7) Excludes internal reference.

(5)

= 5V)

IN

= 0V) ±10 µA

IN

= 50µA) 0.1 V

OL

= 1.6mA) 0.4 V

OL

= 50µA) +4.5 V

OH

= 0.5mA) +2.4 V

OH

= L 20 40 ns

OE

= H 2 10 ns

OE

= 2.5MHz

S

100 µA

At 25°C ±2.0 %FS

±15 ppm/°C

At 25°C ±1.5

±15 ppm/°C

= ±5% 60 82 dB

S

REF
REF

= 2.5V)
= 1.0V)

At 25°C ±35 mV
At 25°C ±14 mV

Operating +4.7 +5.0 5.3 V
Operating 23 27 mA

%FS

ADS803

SBAS074B

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3

PIN CONFIGURATION

Top View SSOP

OVR

B1
B2
B3
B4
B5
B6
B7
B8

B9
B10
B11
B12

CLK

1
2
3
4
5
6
7

ADS803

8

9
10
11
12
13
14

28

VDRV

27

+V

S

26

GND

25

IN

24

GND

23

IN

22

REFT

21

CM

20

REFB

19

VREF

18

SEL

17

GND

16

+V

S

15

OE

PIN DESCRIPTIONS

PIN DESIGNATOR DESCRIPTION

1 OVR Over-Range Indicator
2 B1 Data Bit 1 (MSB)
3 B2 Data Bit 2
4 B3 Data Bit 3
5 B4 Data Bit 4
6 B5 Data Bit 5
7 B6 Data Bit 6
8 B7 Data Bit 7

9 B8 Data Bit 8
10 B9 Data Bit 9
11 B10 Data Bit 10
12 B11 Data Bit 11
13 B12 Data Bit 12 (LSB)
14 CLK Convert Clock Input
15 OE Output Enable
16 +V

S

17 GND Ground
18 SEL Input Range Select
19 V

REF

20 REFB Bottom Reference
21 CM Common-Mode Voltage
22 REFT Top Reference
23 IN Complementary Analog Input
24 GND Analog Ground
25 IN Analog Input (+)
26 GND Analog Ground
27 +V

S

28 VDRV Output Driver Voltage

+5V Supply

Reference Voltage Select

+5V Supply

TIMING DIAGRAM

t

CONV

N + 2

N + 3

N + 4

tLt

N + 5

H

N + 6

Analog In

N + 1

N

t

D

Clock

6 Clock Cycles

Data Out

N – 6N – 5N – 4N – 3N – 2N – 1 N N + 1

Data Invalid

SYMBOL DESCRIPTION MIN TYP MAX UNITS

t

CONV

t

L

t

H

t

D

t

1

t

2

Convert Clock Period 200 1 • 105(ns) ns

Clock Pulse LOW 96 99 ns

Clock Pulse HIGH 96 99 ns

Aperture Delay 3 ns

Data Hold Time, CL = 0pF 3.9 ns

New Data Delay Time, CL = 15pF max 12 ns

t

1

N + 7

t

2

4

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ADS803

SBAS074B

TYPICAL CHARACTERISTICS

100

80

60

40

20

0

SWEPT POWER SFDR

SFDR (dBFS, dBc)

–60 –50 –40 –30 –20 –10 0

Input Amplitude (dBFS)

dBFS

dBc

fIN = 2.48MHz

At TA = full specified temperature range, VS = +5V, specified input range = 1.5V to 3.5V, and single-ended input and sampling rate = 5MHz, unless otherwise specified.

0

–20

–40

–60

Amplitude (dB)

–80

–100

–120

0 0.5 1.0 1.5 2.0 2.5

0

f1 = 1.8MHz at –7dB
f

= 1.9MHz at –7dB

2

–20

IMD (3) = –74dBc

–40

–60

–80

Magnitude (dBFSR)

–100

SPECTRAL PERFORMANCE

Frequency (MHz)

FREQUENCY SPECTRUM

fIN = 500kHz

0

fIN = 2.48MHz

–20

–40

–60

Amplitude (dB)

–80

–100

–120

0 0.5 1.0 1.5 2.0 2.5

1.0

0.5

0

DLE (LSB)

–0.5

SPECTRAL PERFORMANCE

Frequency (MHz)

DIFFERENTIAL LINEARITY ERROR

= 500kHz

f

IN

–120

0 0.5 1.0 1.5 2.0 2.5

4.0

2.0

0

ILE (LSB)

–2.0

–4.0

0 1024 2048 3072 4096

Frequency (MHz)

INTEGRAL LINEARITY ERROR

Output Code

= 500kHz

f

IN

–1.0

0 1024 2048 3072 4096

Output Code

ADS803

SBAS074B

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5