TEXAS INSTRUMENTS ADS807 Technical data

A

D

S

8

0

7

E

SBAS072A – JANUARY 1999 – REVISED JULY 2002

12-Bit, 53MHz Sampling

ANALOG-TO-DIGITAL CONVERTER

ADS807

FEATURES

● SPURIOUS-FREE DYNAMIC RANGE:

82dB at 10MHz f

IN

● HIGH SNR: 67.5dB (2Vp-p), 69dB (3Vp-p)

● LOW POWER: 335mW

●

INTERNAL OR EXTERNAL REFERENCE

● LOW DNL: 0.5LSB

● FLEXIBLE INPUT RANGE: 2Vp-p to 3Vp-p

● SSOP-28 PACKAGE

APPLICATIONS

● COMMUNICATIONS IF PROCESSING

● COMMUNICATIONS BASESTATIONS

● TEST EQUIPMENT

● MEDICAL IMAGING

● VIDEO DIGITIZING

● CCD DIGITIZING

DESCRIPTION

The ADS807 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. The differential nature of this track-and-hold and A/D
converter circuitry minimizes even-order harmonics and gives
excellent common-mode noise immunity. The track-and-hold
can also be operated single-ended.

The ADS807 provides for setting the full-scale range of the
converter without any external reference circuitry. The inter­nal reference can be disabled allowing low drive, internal
references to be used for improved tracking in multichannel
systems.

The ADS807 provides an over-range indicator flag to indicate
an input signal that exceeds the full-scale input range of the
converter. This flag can be used to reduce the gain of front
end gain control circuitry. There is also an output enable pin
to allow for multiplexing and testability on a PC board.

The ADS807 employs digital error correction techniques to
provide excellent differential linearity for demanding imaging
applications.

ADS807

+3V

+2.5V

+2V
+3V

+2.5V

+2V

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.

IN

T/H

IN

(Opt.)

CM

Pipelined

A/D

Converter

Optional External

Reference

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CLK

Timing

Circuitry

Error

Correction

Logic

Internal

Reference

INT/EXT

D0

D11

•

•

•

3-State

Outputs

OE

FS

SEL

Copyright © 1999, Texas Instruments Incorporated

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

ADS807E SSOP-28 DB –40°C to +85°C ADS807E ADS807E Tube, 50

(1)

"""""ADS807E/1K Tape and Reel, 1000

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

SPECIFIED

RANGE MARKING NUMBER MEDIA, QUANTITY

PIN CONFIGURATION

Top View SSOP

GND

Bit 1 (MSB)

Bit 2
Bit 3
Bit 4
Bit 5
Bit 6
Bit 7
Bit 8

Bit 9
Bit 10
Bit 11

Bit 12 (LSB)

CLK

1
2
3
4
5
6
7

ADS807E

8

9
10
11
12
13
14

28
27
26
25
24
23
22
21
20
19
18
17
16
15

VDRV
+V

S

GND
IN
IN
CM
REFT
REFB
GND
OE
INT/EXT
OTR
FS

SEL

+V

S

PIN DESCRIPTIONS

PIN DESIGNATOR DESCRIPTION

1 GND Ground
2 Bit 1 Data Bit 1 (MSB)

3 Bit 2 Data Bit 2
4 Bit 3 Data Bit 3
5 Bit 4 Data Bit 4
6 Bit 5 Data Bit 5
7 Bit 6 Data Bit 6
8 Bit 7 Data Bit 7

9 Bit 8 Data Bit 8
10 Bit 9 Data Bit 9
11 Bit 10 Data Bit 10
12 Bit 11 Data Bit 11
13 Bit 12 Data Bit 12 (LSB)
14 CLK Convert Clock
15 +V
16 FS
17 OTR Out-of-Range Indicator
18 INT/EXT Reference Select: HIGH or Floating = Exter-

19 OE Output Enable
20 GND Ground
21 REFB Bottom Reference/Bypass
22 REFT Top Reference/Bypass
23 CM Common-Mode Voltage Output
24 IN Complementary Analog Input
25 IN Analog Input
26 GND Ground
27 +V
28 VDRV Logic Driver Supply Voltage

S

SEL

S

+5V Supply
HI = 3V, LO = 2V

nal LOW = Internal 50kΩ pull-up.

+5V Supply

2

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ADS807

SBAS072A

ELECTRICAL CHARACTERISTICS

At TA = full specified temperature range, VS = +5V, differential input range = 2V to 3V for each input, sampling rate = 50MHz, unless otherwise noted.

ADS807E

PARAMETER CONDITIONS MIN TYP MAX UNITS
RESOLUTION 12 Tested Bits

SPECIFIED TEMPERATURE RANGE Ambient Air –40 +85 °C
ANALOG INPUT

2V Full-Scale Input Range (Differential) 2Vp-p, INT or EXT Ref 2 3 V
2V Full-Scale Input Range (Single-Ended) 2Vp-p, INT or EXT Ref 1.5 3.5 V
3V Full-Scale Input Range (Differential) 3Vp-p, INT or EXT Ref 1.75 3.25 V
3V Full-Scale Input Range (Single-Ended) 3Vp-p, INT or EXT Ref 1 4 V
Analog Input Bias Current 1 µA
Analog Input Bandwidth 270 MHz
Input Impedance 1.25 || 3 MΩ || pF

CONVERSION CHARACTERISTICS

Sample Rate 10k 53M Samples/s
Data Latency 6 Clock Cycles

DYNAMIC CHARACTERISTICS

Differential Linearity Error (largest code error)

f = 1MHz ±0.5 ±1.0 LSB

f = 10MHz fS = 40MHz ±0.5 ±1.0 LSB
No Missing Codes f
No MIssing Codes f
Integral Nonlinearity Error, f = 1MHz ±2.0 ±4.0 LSBs
Spurious-Free Dynamic Range

(1)

f = 1MHz (–1dB input) 83 dBFS

f = 10MHz (–1dB input) 67 82 dBFS

f = 20MHz (–1dB input) 76 dBFS

f = 40MHz (undersampling) 76 dBFS

f = 1MHz to 10MHz, f
2-Tone Intermodulation Distortion

= 40MHz 2Vp-p, Single-Ended Input 62 69 dBFS

S

(3)

f = 12MHz and 13MHz (–7dB each tone) 71 dBc
Signal-to-Noise Ratio (SNR)

f = 1MHz (–1dB input) 63 68 dB

f = 10MHz (–1dB input) 63 68 dB

f = 20MHz (–dB input) 66 dB

f = 40MHz (undersampling) 67 dB

f = 1MHz to 10MHz, f

f = 1MHz to 10MHz, f

= 40MHz 63 67.5 dB

S

= 40MHz 2Vp-p, Single-Ended Input 60 67 dB

S

f = 1MHz (–1dB input) 3Vp-p 69 dB

f = 10MHz (–1dB input) 3Vp-p 69 dB
Signal-to-(Noise + Distortion) (SINAD)

(4)

f = 1MHz (–1dBFS input) 61 67 dB

f = 10MHz (–1dBFS input) 61 67 dB

f = 20MHz (–1dBFS input) 67 dB

f = 1MHz to 10MHz, f

f = 1MHz to 10MHz, f

= 40MHz 63 67 dB

S

= 40MHz 2Vp-p, Single-Ended Input 60 64 dB

S

f = 1MHz (–1dBFS input) 3Vp-p 69 dB

f = 10MHz (–dBFS Input) 3Vp-p 69 dB
Output Noise Input Grounded 0.2 LSBs rms

Aperture Delay Time 2ns
Aperture Jitter 1.2 ps rms
Over-Voltage Recovery Time 2ns

DIGITAL INPUTS

Logic Family
Convert Command Start Conversion
High Level Input Current

(5)

(VIN = 5V) +50 µA
Low Level Input Current (VIN = 0V) +10 µA
High Level Input Voltage +2.4 V
Low Level Input Voltage +1.0 V
Input Capacitance 5pF

= 50MHz,TA = +25°C Tested

S

= 40MHz, Full Temp Tested

S

CMOS

Rising Edge of Convert Clock

(2)

ADS807

SBAS072A

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3

ELECTRICAL CHARACTERISTICS (Cont.)

At TA = full specified temperature range, VS = +5V, differential input range = 2V to 3V for each input, sampling rate = 50MHz, unless otherwise noted.

ADS807E

PARAMETER CONDITIONS MIN TYP MAX UNITS
DIGITAL OUTPUTS

Logic Family
Logic Coding
Low Output Voltage (I
Low Output Voltage, (I
High Output Voltage, (I
High Output Voltage, (IOH = 0.5mA) VDRV = 5V +4.8 V
Low Output Voltage, (I
High Output Voltage, (I
3-State Enable Time OE = L
3-State Disable Time OE = H

= 50µA) VDRV = 5V +0.1 V

OL

= 1.6mA) VDRV = 5V +0.2 V

OL

= 50µA) VDRV = 5V +4.9 V

OH

= 50µA) VDRV = 3V +0.1 V

OL

= 50µA) VDRV = 3V +2.8 V

OH

(5)
(5)

Output Capacitance 5pF

ACCURACY (Internal Reference, 2Vp-p, Unless Otherwise Noted)

Zero Error (Referred to –FS) at 25°C ±1.0 ±2.0 %FS
Zero Error Drift (Referred to –FS) 16 ppm/°C
Gain Error
Gain Error Drift
Gain Error
Gain Error Drift

(6)

(6)

(7)

(7)

at 25°C ±1.5 ±2.5 %FS

at 25°C ±1.0 ±1.5 %FS

Power-Supply Rejection of Gain ∆VS = ±5% 50 70 dB
REFT Tolerance

2V Full-Scale Deviation From Ideal 3.0V ±10 ±65 mV
3V Full-Scale Deviation From Ideal 3.25V ±20 ±100 mV

REFB Tolerance

2V Full-Scale Deviation From Ideal 2.0V ±10 ±65 mV

3V Full-Scale Deviation From Ideal 1.75V ±20 ±100 mV
External REFT Voltage Range REFB + 0.4 3 V
External REFB Voltage Range 1.70 2 REFT – 0.4 V
Reference Input Resistance 1kΩ

POWER-SUPPLY REQUIREMENTS

Supply Voltage: +V
Supply Current: +I
Power Dissipation: VDRV = 5V External Reference 305 360 mW

S

S

Operating +4.75 +5.0 +5.25 V
Operating 60 mA

VDRV = 3V External Reference 290 350 mW
VDRV = 5V Internal Reference 350 390 mW
VDRV = 3V Internal Reference 335 380 mW

Thermal Resistance,

θ

JA

SSOP-28 50 °C/W

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 as (SINAD – 1.76)/6.02. (5) A 50kΩ pull-down resistor is inserted internally on OE pin. (6) Includes internal reference.
(7) Excludes internal reference.

CMOS

Straight Offset Binary

20 40 ns

210ns

66 ppm/°C

23 ppm/°C

– 1.70 V

S

4

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ADS807

SBAS072A

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

(1)

t

1

(1)

t

2

NOTE: (1) t1 and t2 times are valid for VDRV voltages of +2.7V to +5V.

Convert Clock Period 18.87 100µsns

Clock Pulse LOW 9.4 t

Clock Pulse HIGH 9.4 t

Aperture Delay 2 ns

Data Hold Time, CL = 0pF 2.7 ns

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

/2 ns

CONV

/2 ns

CONV

t

1

N + 7

t

2

ADS807

SBAS072A

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5

TYPICAL CHARACTERISTICS

At TA = full specified temperature range, differential input range = 2V to 3V, sampling rate = 50MHz, and internal reference, unless otherwise noted.

0

–10
–20
–30
–40
–50
–60

Magnitude (dBFS)

–70
–80
–90

–100

0 5 10 15 20 25

0

SNR = 68dBFS

–20

SFDR = 77dBFS

–40

SPECTRAL PERFORMANCE

SNR = 68dBFS

SFDR = 83dBFS

Frequency (MHz)

SPECTRAL PERFORMANCE

fIN = 21MHz

fIN = 1MHz

0

–10
–20
–30
–40
–50
–60

Magnitude (dBFS)

–70
–80
–90

–100

0 5 10 15 20 25

0

–20

–40

SPECTRAL PERFORMANCE

SFDR = 82dBFS

Frequency (MHz)

2-TONE INTERMODULATION DISTORTION

IMD(3) = –71dBc

fIN = 10MHz

SNR = 68dBFS

f1 = 12MHz
f

= 13MHz

2

–60

Magnitude (dBFS)

–80

–100

0 5 10 15 20 25

Frequency (MHz)

SPECTRAL PERFORMANCE

(Sampling Frequency = 27MHz)

0

–20

–40

–60

Magnitude (dBFS)

–80

–100

fIN = 10MHz

SNR = 68dBFS

SFDR = 81dBFS

0 4.5 9.0 13.5

Frequency (MHz)

–60

Magnitude (dBc)

–80

–100

0 5 10 15 20 25

Frequency (MHz)

SPECTRAL PERFORMANCE

(Single-Ended, 2Vp-p)

0

fIN = 10MHz

–20

–40

–60

Magnitude (dBFS)

–80

–100

SNR = 68dBFS

SFDR = 62dBFS

0 4.5 9.0 13.5

Frequency (MHz)

6

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ADS807

SBAS072A