NSC CLC5957MTD Datasheet

N

CLC5957
12-bit, 70MSPS Broadband Monolithic A/D Converter

October 1999

CLC5957

12-bit, 70MSPS Broadband Monolithic A/D Converter

General Description

The CLC5957 is a monolithic 12-bit, 70MSPS analog-to-digital
converter. The device has been optimized for use in IF-sampled
digital receivers and other applications where high resolution,
high sampling rate, wide dynamic range, low power dissipation,
and compact size are required. The CLC5957 features differential
analog inputs, low jitter differential universal clock inputs, a low
distortion track-and-hold with 0-300MHz input bandwidth, a band­gap voltage reference, data valid clock output, TTL compatible
CMOS (3.3V or 2.5V) programmable output logic, and a propri­etary 12-bit multi-stage quantizer. The CLC5957 is fabricated on
the ABIC-V 0.8 micron BiCMOS process.

The CLC5957 features a 74dBc spurious free dynamic range
(SFDR) and a 67dB signal to noise ratio (SNR). The wideband
track-and-hold allows sampling of IF signals to greater than
250MHz. The part produces two-tone, dithered, SFDR of 83dBFS
at 75MHz input frequency. The differential analog input provides
excellent common mode rejection, while the differential universal
clock inputs minimize jitter. The 48-pin TSSOP package provides
an extremely small footprint for applications where space is a
critical consideration. The CLC5957 operates from a single +5V
power supply. Operation over the industrial temperature range of

-40°C to +85°C is guaranteed. National Semiconductor tests
each part to verify compliance with the guaranteed specifications.

Features

• 70MSPS

• Wide dynamic range
SFDR: 74dBc
SFDR w/dither: 85dBFS
SNR: 67dB

• IF sampling capability

• Input bandwidth = 0-300MHz

• Low power dissipation: 640mW

• Very small package: 48-pin TSSOP

• Single +5V supply

• Data valid clock output

• Programmable output levels:

3.3V or 2.5V

Applications

• Cellular base-stations

• Digital communications

• Infrared/CCD imaging

• IF sampling

• Electro-optics

• Instrumentation

• Medical imaging

• High definition video

ME79TG

ME79TG

ME79TG

ME79TG

CLC5957

CL5956

CL5956

CL5956

Actual Size

MTD

IMTD

IMTD

IMTD

N

N

N

N

ADC Block Diagram

3-bit

DAV

IF

Saw

IF

Input

Q

3

12

ADC
Out

~

~

BPF

(150MHz

typ.)

SINAD dBc (BW = 216KHz)

Clock

In

A

T/H

In

© 1999 National Semiconductor Corporation http://www.national.com

Printed in the U.S.A.

3-bit

Q

Single Tone Output Spectrum w/Dither

0

-10

F

-20

-30

-40

-50

-60

-70

Output Level (dBFS)

-80

-90

-100
0

3

Bit Align/Error Correct

Fin = 25.3MHZ

= 66MHz

sample

8284

Frequency (MHz)

3-bit

Q

12 16 20 24 32

3-bit

Q

3

3

First IF Receiver

DVGA

(∆G = 42dB)

Noise

BPF

3-bit (Gain Control)

Decimation/filter = 190/0.8

Output BW = 50M/190 X 0.8 = 210KHz

Receiver SINAD vs. Input Amplitude

90
80
70
60
50
40
30
20
10

0

-125

Input (dBFS)

CLC5957

12-bit

70MSPS

ADC

-50 -25 0-75-100

12

DAV

CLC5902

Dig.

Tuner/

Filter
AGC

20

Ω

Ω

CLC5957 Electrical Characteristics

(V

= +5V, 66MSPS; unless specified) (T

cc

= -40°C, T

min

= +85°C)

max

PARAMETERS CONDITIONS TEMP RATINGS UNITS NOTES

MIN TYP MAX 2

RESOLUTION
DIFF. INPUT VOLTAGE RANGE
MAXIMUM CONVERSION RATE
SNR

SFDR
NO MISSING CODES

f

= 25MHz, A

in

f

= 25MHz, A

in

f

= 5MHz, A

in

= -1dBFS +25°C 63 66 dBFS 1

in

= -1dBFS +25°C 66 74 dBc 1

in

= -1dBFS +25°C Guaranteed 1

in

Full 12 Bits 1
Full 2.048 V
Full 70 75 MSPS 1

DYNAMIC PERFORMANCE

large-signal bandwidth A
overvoltage recovery time A

= -3dBFS +25°C 300 MHz

in

= 1.5FS (0.01%) +25°C 12 ns

in

effective aperture delay (Ta) +25°C -0.41 ns
aperture jitter +25°C 0.3 ps(rms)

NOISE AND DISTORTION

signal-to-noise ratio (w/o 50 harmonics)

f

= 5.0MHz A

in

= 25MHz A

f

in

f

= 75MHz A

in

f

= 150MHz A

in

f

= 250MHz A

in

= -1dBFS Full 67 dBFS

in

= -1dBFS Full 60 66 dBFS 1

in

= -3dBFS Full 65 dBFS

in

= -15dBFS Full 66 dBFS

in

= -15dBFS Full 66 dBFS

in

spurious-free dynamic range

= 5.0MHz A

f

in

f

= 25MHz A

in

f

= 75MHz A

in

f

= 150MHz A

in

f

= 250MHz A

in

= -1dBFS Full 74 dBc

in

= -1dBFS Full 60 74 dBc 1

in

= -3dBFS Full 72 dBc

in

= -15dBFS Full 69 dBc

in

= -15dBFS Full 65 dBc

in

intermodulation distortion

= 149.84MHz, f

f

in1

f

= 249.86MHz, f

in1

= 149.7MHz A

in2

= 249.69MHz A

in2

= -10dBFS +25°C 68 dBFS

in

= -10dBFS +25°C 58 dBFS

in

dithered performance

spurious-free dynamic range

= 19MHz A

f

in

= -6dBFS +25°C 85 dBFS

in

intermodulation distortion

f

= 74MHz, f

in1

= 75MHz A

in2

= -12dBFS +25°C 83 dBFS

in

DC ACCURACY AND PERFORMANCE

differential non-linearity f
integral non-linearity f
no missing codes f

= 5MHz, A

in

= 5MHz, A

in

= 5MHz, A

in

= -1dBFS Full ±0.65 LSB

in

= -1dBFS Full ±1.5 LSB

in

= -1dBFS Full Guaranteed 1

in

offset error Full -30 0 30 mV 1
gain error Full 1.2 %FS
V

ref

Full 2.2 2.37 2.6 V 1

ANALOG INPUTS

analog differential input voltage range Full 2.048 V

pp

analog input resistance (single ended) Full 500
analog input resistance (differential) Full 1000
analog input capacitance (single-ended) Full 2 pF

ENCODE INPUTS (Universal)

VIH +25°C 5 V 3
VIL +25°C 0 V 3
differential input swing +25°C 0.2 V 3

DIGITAL OUTPUTS

output voltage logic LOW +25°C 0.01 0.4 V 1

OUTLEV = 1 (open) logic HIGH +25°C 3.2 3.5 3.8 V 1
OUTLEV = 0 (GND) logic HIGH +25°C 2.4 2.7 3.0 V 1

TIMING (C load < 7pF)

maximum conversion rate Full 70 75 MSPS 1
minimum conversion rate +25°C 10 MSPS
pulse width high Full 7.2 ns
pulse width low Full 7.2 ns
pipeline latency Full 3.0 clk cycle
falling ENCODE to output change (50%) (Tod) +25°C 10 ns
rising ENCODE to DAV change (50%) (Tdv) +25°C 9.6 ns

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2

CLC5957 Electrical Characteristics (V

= +5V, 66MSPS; unless specified) (T

cc

= -40°C, T

min

= +85°C)

max

PARAMETERS CONDITIONS TEMP RATINGS UNITS NOTES

MIN TYP MAX 2

POWER REQUIREMENTS

+5V supply current Full 128 150 mA 1
Power dissipation Full 640 750 mW 1
V

power supply rejection ratio +25°C 64 dB

CC

Min/max ratings are based on product characterization and simulation. Individual parameters are tested as noted. Outgoing quality levels are
determined from tested parameters.

Notes

1) These parameters are 100% tested at 25°C. Sample tested at full
temperature range.

2) Typical specifications are based on the mean test values of
deliverable converters from the first three diffusion lots.

Absolute Maximum Ratings

positive supply voltage (V
differential voltage between any two grounds <100mV

analog input voltage range GND to V
digital input voltage range -0.5V to +V
output short circuit duration (one-pin to ground) infinite

junction temperature 175°C
storage temperature range -65°C to 150°C
lead solder duration (+300°C) 10sec

Note: Absolute maximum ratings are limiting values , to be applied individually, and
beyond which the serviceability of the circuit may be impaired. Functional
operability under any of these conditions is not necessarily implied. Exposure to
maximum ratings for extended periods may affect device reliability.

) -0.5V to +6V

cc

3) See page 7, Figure 3 for ENCODE Inputs circuit.

Recommended Operating Conditions

positive supply voltage (V
analog input voltage range 2.048V
operating temperature range -40°C to +85°C

cc
cc

) +5V ±5%

cc

Pac kage Thermal Resistance

Package

48-pin TSSOP 56°C/W 16°C/W

θ

JA

Reliability Information

Transistor count 5000

diff.

pp

θ

JC

Ordering Information

Model Temperature Range Description

CLC5957MTD -40°C to +85°C 48-pin TSSOP
CLC5957PCASM Fully loaded evaluation board with CLC5957 … ready for test.

ANALOG

INPUT

Ta = -410ps

ENCODE

CLOCK

DAV

CLOCK

DATA

OUTPUT

N

N

Tdv = 9.6ns

N+1

N+1 N+2

Tod = 10ns

N-3 N-2 N-1

N+2

CLC5957 Timing Diagram

3

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CLC5957 Typical Performance Characteristics (V

= +5V)

cc

SNR and SFDR vs. Input Frequency

85
80
75
70
65
60

SFDR

SNR

55
50
45

SNR (dBFS) and SFDR (dBc)

40

0

100

Fs = 66MSPS
A

in

Input Frequency (MHz)

SNR and SFDR vs. Input Frequency

85
80
75
70

SNR

65

SFDR

60
55
50

100

Fs = 40.96MSPS

A

in

45

SNR (dBFS) and SFDR (dBc)

40

0

Input Frequency (MHz)

= -3dBFS

200

= -3dBFS

200

300

300

SNR and SFDR vs. Input Frequency

85
80
75
70
65

SNR

SFDR

60
55
50
45

SNR (dBFS) and SFDR (dBc)

40

0

100

Fs = 52MSPS

= -3dBFS

A

in

200

Input Frequency (MHz)

SNR and SFDR vs. Sample Rate

90

Fin = 24.5MHz

85
80

SFDR

75
70
65

SNR

60
55

SNR (dBc) and SFDR (dBc)

50

40 50 60 70 80

Sample Rate (MSPS)

300

Single Tone Output Spectrum

0

-10

-20

-30

-40

-50

-60

-70

Output Level (dBFS)

-80

-90

-100

Fs = 66MSPS

= -1dBFS

A

in

F

= 24.5MHz

in

0 5 10 15 35

20

25

Frequency (MHz)

Differential Non-Linearity

1.0

0.5

0

Fs = 66MSPS

F

= 5MHz

in

DNL (LSBs)

-0.5

-1.0
0 512 1024 1536 3584

2048

2560

Output Code

3072

Single Tone Output Spectrum (w/Dither)

0

-10

-20

-30

-40

-50

-60

-70

Output Level (dBFS)

-80

-90

-100

30

Fs = 66MSPS

= - 6dBFS

A

in

F

= 24.5MHz

in

Dither Signal = 500kHz @ - 28dBFS

0 5 10 15 35

20

30

25

Frequency (MHz)

Integral Non-Linearity

4096

2.0

1.5

1.0

0.5
0

-0.5

INL (LSBs)

-1.0

-1.5

-2.0

Fs = 66MSPS

F

= 5MHz

in

0 512 1024 1536 3584

2048

2560

3072

4096

Output Code

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