Rainbow Electronics MAX1011 User Manual

General Description

The MAX1011 is a 6-bit analog-to-digital converter
(ADC) that combines high-speed, low-power operation
with a user-selectable input range, an internal refer­ence, and a clock oscillator. The ADC converts analog
signals into binary-coded digital outputs at sampling
rates up to 90Msps. The ability to directly interface with
baseband signals makes the MAX1011 ideal for use in
a wide range of communications and instrumentation
applications.

The MAX1011’s input amplifier features a true differential
input, a -0.5dB analog bandwidth of 55MHz, and a user­programmable input full-scale range of 125mVp-p,
250mVp-p, or 500mVp-p. With an AC-coupled signal,
input offset is typically less than 1/4LSB. Dynamic per­formance is 5.85 effective number of bits (ENOB) with a
20MHz analog input signal, or 5.7 ENOB with a 50MHz
signal.

The MAX1011 operates with +5V analog and +3.3V digi­tal supplies for easy interfacing to +3.3V-logic-compatible
digital signal processors and microprocessors. It comes
in a 24-pin QSOP package.

Applications

IF Sampling Receivers
VSAT Receivers
Wide Local Area Networks (WLANs)
Instrumentation

Features

♦ High Sampling Rate: 90Msps
♦ Low Power Dissipation: 215mW
♦ Excellent Dynamic Performance:

5.85 ENOB with 20MHz Analog Input

5.7 ENOB with 50MHz Analog Input

♦ ±1/4LSB INL and DNL (typ)
♦ ±1/4LSB Input Offset (typ)
♦ Internal Bandgap Voltage Reference
♦ Internal Oscillator with Overdrive Capability
♦ 55MHz (-0.5dB) Bandwidth Input Amplifier with

True Differential Input

♦ User-Selectable Full-Scale Range

(125mVp-p, 250mVp-p, or 500mVp-p)

♦ Single-Ended or Differential Input Drive
♦ Flexible, 3.3V, CMOS-Compatible Digital Outputs

MAX1011

Low-Power, 90Msps, 6-Bit ADC

________________________________________________________________

Maxim Integrated Products

1

MAX1011

D0–D5

DCLK

TNK+
TNK-

INPUT

AMP

IN+

IN-

GAIN

DATA

BUFFER

6

ADC

VREF

BANDGAP

REFERENCE

OCC+ OCC-

6

OFFSET

CORREC-

TION

CLOCK

OUT

CLOCK
DRIVER

Functional Diagram

19-1335; Rev 0a; 2/98

PART

MAX1011CEG 0°C to +70°C

TEMP. RANGE PIN-PACKAGE

24 QSOP

EVALUATION KIT

AVAILABLE

Pin Configuration appears at end of data sheet.

For free samples & the latest literature: http://www.maxim-ic.com, or phone [phone]
For small orders, phone [phone] ext. 3468.

Ordering Information

MAX1011

Low-Power, 90Msps, 6-Bit ADC

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

DC ELECTRICAL CHARACTERISTICS

(VCC= +5V ±5%, V

CCO

= 3.3V ±300mV, TA= T

MIN

to T

MAX

, unless otherwise noted.)

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.

VCCto GND ..........................................................-0.3V to +6.5V

V

CCO

to OGND......................................................-0.3V to +6.5V

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

Digital and Clock Output Pins to OGND...-0.3V to V

CCO

(10sec)

All Other Pins to GND...............................................-0.3V to V

CC

Continuous Power Dissipation (TA= +70°C)

24-Pin QSOP (derate 10mW/°C above +70°C)...........800mW

Operating Temperature Range...............................0°C to +70°C

Storage Temperature Range.............................-65°C to +150°C

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

CONDITIONS

LSB-0.5 ±0.25 0.5INLIntegral Nonlinearity

Bits6RESResolution

UNITSMIN TYP MAXSYMBOLPARAMETER

GAIN = open (mid gain)

GAIN = VCC(high gain)

No missing codes over temperature

237.5 250 262.5V

FSM

118.75 125 131.25V

FSH

LSB-0.5 ±0.25 0.5DNLDifferential Nonlinearity

Other analog input driven with external source
(Note 2)

Guaranteed by design

V1.75 2.75V

CM

GAIN = GND (low gain)

Common-Mode Voltage Range

pF1.5 3C

IN

Input Capacitance

kΩ13 20 29R

IN

Input Resistance

V2.25 2.35 2.45V

AOC

Input Open-Circuit Voltage

mVp-p

475 500 525V

FSL

Full-Scale Input Range

Other oscillator input tied to VCC+ 0.3V

I

SOURCE

= 50µA V0.7V

CCO

V

OH

Digital Outputs Logic-High
Voltage

kΩ4.8 8 12.1R

OSC

Oscillator Input Resistance

I

SINK

= 400µA V0.5V

OL

Digital Outputs Logic-Low
Voltage

VCC= 4.75V to 5.25V (Note 3)
20MHz, full-scale analog inputs,

CL= 15pF (Note 4)

mW215PDPower Dissipation

mA8.5 13.8I

CCO

Digital Outputs Supply Current

dB-65 -40PSRRPower-Supply Rejection Ratio

mA37 63.5I

CC

Supply Current

DC ACCURACY (Note 1)

INVERTING AND NONINVERTING ANALOG INPUTS

OSCILLATOR INPUTS

DIGITAL OUTPUTS (D0–D5)

POWER SUPPLY

MAX1011

Low-Power, 90Msps, 6-Bit ADC

_______________________________________________________________________________________ 3

AC ELECTRICAL CHARACTERISTICS

(VCC= +5V ±5%, V

CCO

= 3.3V ±300mV, TA= +25°C, unless otherwise noted.)

Note 1: Best-fit straight-line linearity method.
Note 2: A typical application will AC couple the analog input to the DC bias level present at the analog inputs (typically 2.35V).

However, it is also possible to DC couple the analog input (using differential or single-ended drive) within this common­mode input range (Figures 4 and 5).

Note 3: PSRR is defined as the change in the mid-gain, full-scale range as a function of the variation in V

CC

supply voltage,

expressed in decibels.

Note 4: The current in the V

CCO

supply is a strong function of the capacitive loading on the digital outputs. To minimize supply tran­sients and achieve optimal dynamic performance, reduce the capacitive-loading effects by keeping line lengths on the dig­ital outputs to a minimum.

Note 5: Offset-correction compensation enabled, 0.22µF at compensation inputs (Figures 2 and 3).
Note 6: t

PD

and t

SKEW

are measured from the 1.4V level of the output clock, to the 1.4V level of either the rising or falling edge of a

data bit. t

DCLK

is measured from the 50% level of the clock-overdrive signal on TNK+ to the 1.4V level of DCLK. The capac-

itive load on the outputs is 15pF.

GAIN = GND, open, V

CC

GAIN = open (mid gain), fIN= 50MHz,

-1dB below full scale

GAIN = open (mid gain)

5.7

ENOB

M

5.6 5.85

Effective Number of Bits

GAIN = open (mid gain)

GAIN = GND (low gain)

Guaranteed by design

CONDITIONS

MHz55BWAnalog Input -0.5dB Bandwidth

Msps90f

MAX

Maximum Sample Rate

GAIN = VCC(high gain)

LSBOFFInput Offset (Note 5) -0.5 0.5

dB35.5 37SINAD

Signal-to-Noise Plus Distortion
Ratio

Bits

5.85ENOB

L

5.8ENOB

H

(Note 6)

(Note 6)

ns1t

SKEW

Data Valid Skew

ns3.0t

PD

Clock to Data Propagation
Delay

UNITSMIN TYP MAXSYMBOLPARAMETER

TNK+ to DCLK (Note 6) ns4.5t

DCLK

Input to DCLK Delay

Figure 8 ns5.5t

AD

Aperture Delay

Figure 8

clock
cycle

1PDPipeline Delay

TIMING CHARACTERISTICS (Data outputs: RL= 1MΩ, CL= 15pF)

DYNAMIC PERFORMANCE (Gain = open, external 90MHz clock (Figure 7), VIN= 20MHz sine, amplitude -1dB below

full scale, unless otherwise noted.)

MAX1011

Low-Power, 90Msps, 6-Bit ADC

4 _______________________________________________________________________________________

__________________________________________Typical Operating Characteristics

(VCC= +5V ±5%, V

CCO

= 3.3V ±300mV, f

CLK

= 90Msps, GAIN = open (midgain) MAX1011 evaluation kit, TA= +25°C, unless

otherwise noted.)

6.0

5.0
10

100

EFFECTIVE NUMBER OF BITS

vs. ANALOG INPUT FREQUENCY

5.2

MAX1011-01

ANALOG INPUT FREQUENCY (MHz)

EFFECTIVE NUMBER OF BITS

5.4

5.6

5.8

f

CLK

= 90Msps

-1.0
1 10 100

ANALOG INPUT BANDWIDTH

-0.8

MAX1011-02

ANALOG INPUT FREQUENCY (MHz)

MAGNITUDE (dB)

-0.6

-0.2

-0.4

0

5.5
1 10 100

EFFECTIVE NUMBER OF BITS

vs. SAMPLING/CLOCK FREQUENCY

5.6

MAX1011-03

CLOCK FREQUENCY (MHz)

EFFECTIVE NUMBER OF BITS

5.7

5.9

5.8

6.0

fIN = 20MHz

-50

1k 100k 1M

OSCILLATOR OPEN-LOOP PHASE NOISE

vs. FREQUENCY OFFSET

-110

-130

-90

-70

MAX1011-04

FREQUENCY OFFSET FROM CARRIER (Hz)

PHASE NOISE (dBc)

10k

0.50

-0.50
0 64

INTEGRAL NONLINEARITY

vs. CODE

-0.25

0.25

MAX1011-06

CODE

INL (LSB)

10 20 30 40 50 60

0

0.50

-0.50
0 64

DIFFERENTIAL NONLINEARITY

vs. CODE

-0.25

0.25

MAX1003-07

CODE

DNL (LSB)

10 20 30 40 50 60

0

-80

-60

-40

-20

0

0 9 18 27 36 45

FFT PLOT

MAX1011-05

FREQUENCY (MHz)

AMPLITUDE (dB)

fIN = 19.9512MHz
f

CLK

= 90.000MHz
1024 POINTS
AC-COUPLED
SINGLE-ENDED
AVERAGED