Rainbow Electronics MAX1181 User Manual

General Description

The MAX1181 is a +3V, dual 10-bit, analog-to-digital
converter (ADC) featuring fully-differential wideband
track-and-hold (T/H) inputs, driving two pipelined, nine­stage ADCs. The MAX1181 is optimized for low-power,
high-dynamic performance applications in imaging,
instrumentation, and digital communication applica­tions. The MAX1181 operates from a single +2.7V to
+3.6V supply, consuming only 246mW, while delivering
a typical signal-to-noise ratio (SNR) of 59dB at an input
frequency of 20MHz and a sampling rate of 80Msps.
The T/H driven input stages incorporate 400MHz (-3dB)
input amplifiers. The converters may also be operated
with single-ended inputs. In addition to low operating
power, the MAX1181 features a 2.8mA sleep mode, as
well as a 1µA power-down mode to conserve power
during idle periods.

An internal +2.048V precision bandgap reference sets
the full-scale range of the ADC. A flexible reference
structure allows the use of the internal or external
reference, if desired for applications requiring
increased accuracy or a different input voltage range.

The MAX1181 features parallel, CMOS-compatible
three-state outputs. The digital output format is set to
two’s complement or straight offset binary through a
single control pin. The device provides for a separate
output power supply of +1.7V to +3.6V for flexible inter­facing. The MAX1181 is available in a 7mm ✕ 7mm, 48­pin TQFP package, and is specified for the extended
industrial (-40°C to +85°C) temperature range.

Pin-compatible higher and lower speed versions of the
MAX1181 are also available. Please refer to the
MAX1180 datasheet for 105Msps, the MAX1182
datasheet for 65Msps, the MAX1183 datasheet for
40Msps, and the MAX1184 datasheet for 20Msps. In
addition to these speed grades, this family includes a
20Msps multiplexed output version (MAX1185), for
which digital data is presented time-interleaved on a
single, parallel 10-bit output port.

Applications

High Resolution Imaging

I/Q Channel Digitization

Multichannel IF Undersampling

Instrumentation

Video Application

Features

♦ Single +3V Operation

♦ Excellent Dynamic Performance:

59dB SNR at fIN= 20MHz
73dB SFDR at fIN= 20MHz

♦ Low Power:

82mA (Normal Operation)

2.8mA (Sleep Mode)
1µA (Shutdown Mode)

♦ 0.02dB Gain and 0.25° Phase Matching (typ)

♦ Wide ±1Vp-p Differential Analog Input Voltage

Range

♦ 400MHz, -3dB Input Bandwidth

♦ On-Chip +2.048V Precision Bandgap Reference

♦ User-Selectable Output Format—Two’s

Complement or Offset Binary

♦ 48-Pin TQFP Package with Exposed Pad for

Improved Thermal Dissipation

♦ Evaluation Kit Available

MAX1181

Dual 10-Bit, 80Msps, +3V, Low-Power ADC with

Internal Reference and Parallel Outputs

________________________________________________________________ Maxim Integrated Products 1

Pin Configuration

Ordering Information

19-2093; Rev 0; 7/01

For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.

Functional Diagram appears at end of data sheet.

PART TEMP. RANGE PIN-PACKAGE

MAX1181ECM -40°C to +85°C 48 TQFP-EP

REFN

REFP

REFIN

REFOUT

D9A

D8A

D7A

D6A

D5A

D4A

D3A

D2A

COM

V
GND
INA+
INA-

V
GND
INB­INB+
GND

V

CLK

4847464544434241403938

1

2

DD

3

4

5

6

DD

7

8

9

10

11

DD

12

1314151617181920212223

DD

V

GND

MAX1181

DD

T/B

V

GND

48 TQFP-EP

SLEEP

OE

PD

D9B

D8B

D7B

37

24

D6B

36

D1A
D0A

35

OGND

34

OV

33

DD

OV

32

DD

OGND

31

D0B

30

D1B

29

D2B

28

D3B

27

D4B

26

D5B

25

ELECTRICAL CHARACTERISTICS

(VDD= +3V, OVDD= +2.5V; 0.1µF and 1.0µF capacitors from REFP, REFN, and COM to GND; REFOUT connected to REFIN through
a 10kΩ resistor, V

IN

= 2V

p-p

(differential w.r.t. COM), CL= 10pF at digital outputs (Note 5), f

CLK

= 83.333MHz (50% duty cycle), TA=

T

MIN

to T

MAX

, unless otherwise noted. Typical values are at TA= +25°C.)

MAX1181

Dual 10-Bit, 80Msps, +3V, Low-Power ADC with
Internal Reference and Parallel Outputs

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

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

VDD, OVDDto GND ...............................................-0.3V to +3.6V

OGND to GND.......................................................-0.3V to +0.3V

INA+, INA-, INB+, INB- to GND ...............................-0.3V to V

DD

REFIN, REFOUT, REFP, REFN, CLK,

COM to GND ............................................-0.3V to (V

DD

+ 0.3V)

OE, PD, SLEEP, T/B, D9A–D0A,

D9B–D0B to OGND ................................-0.3V to (OV

DD

+ 0.3V)

Continuous Power Dissipation (T

A

= +70°C)

48-Pin TQFP (derate 12.5mW/°C above +70°C).........1000mW

Operating Temperature Range ...........................-40°C to +85°C

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

Storage Temperature Range .............................-60°C to +150°C

Lead Temperature (soldering, 10s) .................................+300°C

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

DC ACCURACY

Resolution 10 Bits

Integral Nonlinearity INL fIN = 7.47MHz ±0.6 ±2.2 LSB

Differential Nonlinearity DNL fIN = 7.47MHz, no missing codes guaranteed ±0.4 ±1.0 LSB
Offset Error < ±1 ±1.7 % FS
Gain Error 0 ±2 % FS

ANALOG INPUT

Differential Input Voltage Range V

Common-Mode Input Voltage
Range

Input Resistance R

Input Capacitance C

CONVERSION RATE

Maximum Clock Frequency f

Data Latency 5

DYNAMIC CHARACTERISTICS (f

Signal-to-Noise Ratio SNR

Signal-to-Noise And Distortion

th

(up to 5

Spurious-Free Dynamic
Range

Third-Harmonic Distortion HD3

harmonic)

DIFF

V

CLK

= 83.333MHz, 4096-point FFT)

CLK

SINAD

SFDR

Differential or single-ended inputs ±1.0 V

CM

Switched capacitor load 25 kΩ

IN

IN

f

= 7.47MHz, TA = +25°C 56.5 59.5

INA or B

f

= 20MHz, TA = +25°C5659

INA or B

= 39.9MHz (Note 1) 59

f

INA or B

f

= 7.47MHz, TA = +25°C5659

INA or B

f

= 20MHz, TA = +25°C 55.3 58.5

INA or B

f

= 39.9MHz (Note 1) 58.5

INA or B

f

= 7.47MHz, TA = +25°C6575

INA or B

f

= 20MHz, TA = +25°C6473

INA or B

fINA or B

f

f

f

= 39.9MHz, (Note 1) 71

= 7.47MHz -76

INA or B

= 20MHz -76

INA or B

= 39.9MHz (Note 1) -75

INA or B

VDD/2

± 0.5

5pF

80 MHz

V

Clock

Cycles

dB

dB

dBc

dBc

MAX1181

Dual 10-Bit, 80Msps, +3V, Low-Power ADC with

Internal Reference and Parallel Outputs

_______________________________________________________________________________________ 3

ELECTRICAL CHARACTERISTICS (continued)

(VDD= +3V, OVDD= +2.5V; 0.1µF and 1.0µF capacitors from REFP, REFN, and COM to GND; REFOUT connected to REFIN through
a 10kΩ resistor, V

IN

= 2V

p-p

(differential w.r.t. COM), CL= 10pF at digital outputs (Note 5), f

CLK

= 83.333MHz (50% duty cycle), TA=

T

MIN

to T

MAX

, unless otherwise noted. Typical values are at TA= +25°C.)

,

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Intermodulation Distortion
(first five odd-order IMDs)

Total Harmonic Distortion
(first five harmonics)

Small-Signal Bandwidth Input at -20dB FS, differential inputs 500 MHz

Full-Power Bandwidth FPBW Input at -0.5dB FS, differential inputs 400 MHz

Aperture Delay t

Aperture Jitter t

Overdrive Recovery Time For 1.5 x full-scale input 2 ns
Differential Gain ±1%
Differential Phase ±0.25 degrees

Output Noise INA+ = INA- = INB+ = INB- = COM 0.2 LSB

INTERNAL REFERENCE

Reference Output Voltage REFOUT

Reference Temperature
Coefficient

Load Regulation 1.25 mV/mA

BUFFERED EXTERNAL REFERENCE (V

REFIN Input Voltage V

Positive Reference Output
Voltage

Negative Reference Output
Voltage

Differential Reference Output
Voltage Range

REFIN Resistance R

Maximum REFP, COM Source
Current

Maximum REFP, COM Sink
Current

Maximum REFN Source Current I

Maximum REFN Sink Current I

UNBUFFERED EXTERNAL REFERENCE (V

REFP, REFN Input Resistance

= 38.1546MHz at -6.5dB FS

f

INA or B

= 41.9532MHz at -6.5dB FS

IMD

f

INA or B

(Note 2)

f

= 7.47MHz, TA = +25°C

INA or B

f

THD

AD

AJ

TC

REF

REFIN

V

REFP

V

REFN

∆V

REF

REFIN

I

SOURCE

I

SINK

SOURCE

SINK

R

REFP

R

REFN

REFIN

=+2.048V)

REFIN

= 20MHz, TA = +25°C -70 -63

INA or B

= 39.9MHz (Note 1) -70

f

INA or B

∆V

REF

= V

REFP

- V

REFN

= AGND, reference voltage applied to REFP, REFN and COM )

Measured between REFP and COM and
REFN and COM

-73.5 dBc

-73 -64

1ns

2ps

2.048

±3%

60 ppm/°C

2.048 V

2.012 V

0.988 V

0.98 1.024 1.07 V

>50 MΩ

>5 mA

250 µA

250 µA

>5 mA

4kΩ

dBc

RMS

RMS

V

MAX1181

Dual 10-Bit, 80Msps, +3V, Low-Power ADC with
Internal Reference and Parallel Outputs

4 _______________________________________________________________________________________

ELECTRICAL CHARACTERISTICS (continued)

(VDD= +3V, OVDD= +2.5V; 0.1µF and 1.0µF capacitors from REFP, REFN, and COM to GND; REFOUT connected to REFIN through
a 10kΩ resistor, V

IN

= 2V

p-p

(differential w.r.t. COM), CL= 10pF at digital outputs (Note 5), f

CLK

= 83.333MHz (50% duty cycle), TA=

T

MIN

to T

MAX

, unless otherwise noted. Typical values are at TA= +25°C.)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Differential Reference Input
Voltage

COM Input Voltage V

REFP Input Voltage V

REFN Input Voltage V

DIGITAL INPUTS (CLK, PD, OE, SLEEP, T/B)

Input High Threshold V

Input Low Threshold V

Input Hysteresis V

Input Leakage

Input Capacitance C

DIGITAL OUTPUTS (D9A–D0A, D9B–D0B)

Output Voltage Low V

Output Voltage High V

Three-State Leakage Current I

Three-State Output Capacitance C

POWER REQUIREMENTS

Analog Supply Voltage Range V

Output Supply Voltage Range OV

Analog Supply Current I

Output Supply Current I

∆V

REFN

REF

COM

REFP

REF

= V

REFP

- V

REFN

∆V

CLK

IH

PD, OE, SLEEP, T/B

CLK

IL

PD, OE, SLEEP, T/B

HYST

I

I

LEAK

OUT

VDD

V

IH

IL

IN

OL

OH

= OV

IH

VIL = 0 ±5

I

SINK

I

SOURCE

OE = OV
OE = OV

DD

DD

Operating, f

or V

DD

(CLK) ±5

DD

= 200µA 0.2 V

= 200µA

DD

DD

= 20MHz at -0.5dB FS 82 97

INA or B

Sleep mode 2.8
Shutdown, clock idle, PD = OE = OV

Operating, CL = 15pF , f

-0.5dB FS

OVDD

Sleep mode 100 µA
Shutdown, clock idle, PD = OE = OV

INA or B

DD

= 20MHz at

DD

1.024

± 10%

VDD/2
± 10%

V

COM

+ ∆V

V

- ∆V

REF

COM

REF

/2

/2

0.8 x
V

DD

0.8 x

OV

DD

0.2 x
V

DD

0.2 x

OV

DD

0.1 V

5pF

OV

DD

- 0.2

±10 µA

5pF

2.7 3.0 3.6 V

1.7 2.5 3.6 V

115µA

13 mA

210µA

V

V

V

V

V

V

µA

V

mA

MAX1181

Dual 10-Bit, 80Msps, +3V, Low-Power ADC with

Internal Reference and Parallel Outputs

_______________________________________________________________________________________ 5

Typical Operating Characteristics

(VDD= +3V, OVDD= +2.5V, internal reference, differential input at -0.5dB FS, f

CLK

= 80.0005678MHz, CL≈ 10pF. TA= +25°C,

unless otherwise noted.)

ELECTRICAL CHARACTERISTICS (continued)

(VDD= +3V, OVDD= +2.5V; 0.1µF and 1.0µF capacitors from REFP, REFN, and COM to GND; REFOUT connected to REFIN through
a 10kΩ resistor, V

IN

= 2V

p-p

(differential w.r.t. COM), CL= 10pF at digital outputs (Note 5), f

CLK

= 83.333MHz (50% duty cycle), TA=

T

MIN

to T

MAX

, unless otherwise noted. Typical values are at TA= +25°C.)

Note 1: SNR, SINAD, THD, SFDR, and HD3 are based on an analog input voltage of -0.5dB FS, referenced to a +1.024V full-scale

input voltage range.

Note 2: Intermodulation distortion is the total power of the intermodulation products relative to the individual carrier. This number is

6dB or better, if referenced to the two-tone envelope.

Note 3: Digital outputs settle to V

IH

, VIL. Parameter guaranteed by design.

Note 4: With REFIN driven externally, REFP, COM, and REFN are left floating while powered down.
Note 5: Equivalent dynamic performance is obtainable over full OV

DD

range with reduced CL.

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Power Supply Rejection PSRR

TIMING CHARACTERISTICS

CLK Rise to Output Data Valid t

Output Enable Time t

Output Disable Time t

CLK Pulse Width High t

CLK Pulse Width Low t

Wake-Up Time t

CHANNEL-TO-CHANNEL MATCHING

Crosstalk f

Gain Matching f

Phase Matching f

Operating, f

= 20MHz at -0.5dB FS 246 291 mW

INA or B

Sleep mode 8.4Power Dissipation PDISS
Shutdown, clock idle, PD = OE = OV
Offset ±0.2 mV/V
Gain ±0.1 %/V

DO

ENABLE

DISABLE

CH

WAKE

Figure 3 (Note 3) 5 8 ns

Figure 4 10 ns

Figure 4 1.5 ns
Figure 3 clock period: 12ns 6 ±1ns
Figure 3 clock period: 12ns 6 ±1ns

CL

Wakeup from sleep mode (Note 4) 0.28

Wakeup from shutdown (Note 4) 1.5

= 20MHz at -0.5dB FS -70 dB

INA or B

= 20MHz at -0.5dB FS 0.02 ±0.2 dB

INA or B

= 20MHz at -0.5dB FS 0.25 degrees

INA or B

DD

345

µW

µs

FFT PLOT CHA (8192-POINT RECORD,

DIFFERENTIAL INPUT)

0

CHA

-10

-20

-30

-40

-50

-60

AMPLITUDE (dB)

-70

-80

-90

-100
010155 2025303540

ANALOG INPUT FREQUENCY (MHz)

f

= 6.0449MHz

INA

= 7.5099MHz

f

INB

= 80.000568MHz

f

CLK

AINA = -0.46dB FS

MAX1181 toc01

FFT PLOT CHB (8192-POINT RECORD,

DIFFERENTIAL INPUT)

0

f

CHB

-10

-20

-30

-40

-50

-60

AMPLITUDE (dB)

-70

-80

-90

-100
010155 2025303540

ANALOG INPUT FREQUENCY (MHz)

= 6.0449MHz

INA

= 7.5099MHz

f

INB

= 80.000568MHz

f

CLK

AINB = -0.52dB FS

FFT PLOT CHA (8192-POINT RECORD,

DIFFERENTIAL INPUT)

MAX1181 toc02

0

CHA

-10

-20

-30

-40

-50

-60

AMPLITUDE (dB)

-70

-80

-90

-100
010155 2025303540

ANALOG INPUT FREQUENCY (MHz)

f

INA

f

INB

f

CLK

AINA = -0.52 dB FS

= 19.9123MHz
= 24.9123MHz

= 80.000568MHz

MAX1181 toc03

MAX1181

Dual 10-Bit, 80Msps, +3V, Low-Power ADC with
Internal Reference and Parallel Outputs

6 _______________________________________________________________________________________

Typical Operating Characteristics (continued)

(VDD= +3V, OVDD= +2.5V, internal reference, differential input at -0.5dB FS, f

CLK

= 80.0005678MHz, CL≈ 10pF. TA= +25°C,

unless otherwise noted.)

FFT PLOT CHB (8192-POINT RECORD,

DIFFERENTIAL INPUT)

0

f

= 19.9123MHz

INA

-10

-20

-30

-40

-50

-60

AMPLITUDE (dB)

-70

-80

-90

-100

= 24.9123MHz

f

INB

= 80.000568MHz

f

CLK

AINB = -0.53 dB FS

010155 2025303540

ANALOG INPUT FREQUENCY (MHz)

CHB

MAX1181 toc04

FFT PLOT CHA (8192-POINT RECORD,

DIFFERENTIAL INPUT)

0

f

= 40.4202MHz

INA

-10

-20

-30

-40

-50

-60

AMPLITUDE (dB)

-70

-80

-90

-100

= 47.0413MHz

f

INB

= 80.000568MHz

f

CLK

AINA = -0.52dB FS

010155 2025303540

ANALOG INPUT FREQUENCY (MHz)

FFT PLOT CHB (8192-POINT RECORD,

DIFFERENTIAL INPUT)

0

f

= 40.4202MHz

CHA

MAX1181 toc05

INA

-10

-20

-30

-40

-50

-60

AMPLITUDE (dB)

-70

-80

-90

-100

= 47.0413MHz

f

INB

= 80.000568MHz

f

CLK

AINB = -0.53dB FS

010155 2025303540

ANALOG INPUT FREQUENCY (MHz)

CHB

MAX1181 toc06

TWO-TONE IMD PLOT (8192-POINT RECORD,

COHERENT SAMPLING)

0

f

= 38.1545676MHz

IN1

-10
= 41.9631884MHz

f

IN2

-20

-30

-40

-50

-60

AMPLITUDE (dB)

-70

-80

-90

-100

= 80.0005678MHz

f

CLK

AIN = 6.5dB FS
TWO-TONE ENVELOPE =

-0.52dB FS

2nd ORDER IMD

010155 2025303540

ANALOG INPUT FREQUENCY (MHz)

f

IN1

f

TOTAL HARMONIC DISTORTION vs.

ANALOG INPUT FREQUENCY

-65

-68

-71

THD (dB)

-74

-77

CHB

CHA

SIGNAL-TO-NOISE RATIO vs.

ANALOG INPUT FREQUENCY

61

60

MAX1181 toc07

IN2

59

58

SNR (dB)

57

56

55

CHB

10

ANALOG INPUT FREQUENCY (MHz)

CHA

MAX1181 toc08

SINAD (dB)

100

SIGNAL-TO-NOISE + DISTORTION

vs. ANALOG INPUT FREQUENCY

61

60

59

58

57

10

ANALOG INPUT FREQUENCY (MHz)

CHB

MAX1181 toc09

CHA

100

FULL-POWER INPUT BANDWIDTH vs.

MAX1181 toc10

SPURIOUS-FREE DYNAMIC RANGE vs.

ANALOG INPUT FREQUENCY

87

83

79

75

SFDR (dB)

71

67

CHA

CHB

MAX1181 toc11

-2

GAIN (dB)

-4

-6

ANALOG INPUT FREQUENCY

(SINGLE-ENDED)

6

4

2

0

MAX1181 toc12

-80
10

ANALOG INPUT FREQUENCY (MHz)

100

63

10

ANALOG INPUT FREQUENCY (MHz)

100

-8
1 10 100 1000

ANALOG INPUT FREQUENCY (MHz)