Rainbow Electronics MAX1116 User Manual

General Description

The MAX1115/MAX1116 low-power, 8-bit, analog-to­digital converters (ADCs) feature an internal track/hold
(T/H), voltage reference, VDDmonitor, clock, and serial
interface. The MAX1115 is specified from +2.7V to
+5.5V, and the MAX1116 is specified from +4.5V to
+5.5V. Both parts consume only 175µA at 100ksps.

The full-scale analog input range is determined by the
internal reference of +2.048V (MAX1115) or +4.096V
(MAX1116). The MAX1115/MAX1116 also feature
AutoShutdown™ power-down mode which reduces
power consumption to <1µA when the device is not in
use. The 3-wire serial interface directly connects to
SPI™, QSPI™, and MICROWIRE™ devices without
external logic. Conversions up to 100ksps are per­formed using an internal clock.

The MAX1115/MAX1116 are available in an 8-pin
SOT23 package with a footprint that is just 30% of an 8­pin SO.

________________________Applications

Low-Power, Hand-Held Portable Devices

System Diagnostics

Battery-Powered Test Equipment

Receive Signal Strength Indicators

4mA to 20mA Powered Remote Data-Acquisition
Systems

Features

♦ Single Supply

+2.7V to +3.6V (MAX1115)
+4.5V to +5.5V (MAX1116)

♦ Input Voltage Range: 0 to V

REF

♦ Internal Track/Hold; 100kHz Sampling Rate

♦ Internal Reference

+2.048V (MAX1115)
+4.096V (MAX1116)

♦ SPI/QSPI/MICROWIRE-Compatible Serial Interface

♦ Small 8-Pin SOT23 Package

♦ Automatic Power-Down

♦ Low Power

175µA at 100ksps
18µA at +3V and 10ksps
1µA in Power-Down Mode

MAX1115/MAX1116

Single-Supply, Low-Power, Serial 8-Bit ADCs

________________________________________________________________ Maxim Integrated Products 1

Pin Configuration

19-1822; Rev 0; 11/00

Ordering Information

AutoShutdown is a trademark of Maxim Integrated Products.

SPI/QSPI are trademarks of Motorola, Inc.

MICROWIRE is a trademark of National Semiconductor, Corp.

For price, delivery, and to place orders, please contact Maxim Distribution at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.

PART TEMP. RANGE

MAX1115EKA -40°C to +85°C 8 SOT23 AADY

MAX1116EKA -40°C to +85°C 8 SOT23 AADX

PIN­PA CK A G E

TO P

M A RK

TOP VIEW

V

1

DD

CH0

2

MAX1115

3

MAX1116

4

SOT23

I.C.

GND

8

7

6

5

SCLK

DOUT

CONVST

I.C.

MAX1115/MAX1116

Single-Supply, Low-Power, Serial 8-Bit ADCs

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

(VDD= +2.7V to +3.6V (MAX1115), VDD= +4.5V to +5.5V (MAX1116), 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.

VDDto GND...........................................................-0.3V to +6.0V

CH0 to GND ...............................................-0.3V to (V

DD

+ 0.3V)

Digital Output to GND ................................-0.3V to (V

DD

+ 0.3V)

Digital Input to GND ..............................................-0.3V to +6.0V

Maximum Current into Any Pin .........................................±50mA

Continuous Power Dissipation (T

A

= +70°C)

8-Pin SOT23 (derate 8.9mW/°C above +70°C)............714mW

Operating Temperature Range

MAX111_EKA ..................................................-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 8 bits

Relative Accuracy (Note 1) INL ±1 LSB

Differential Nonlinearity DNL ±1 LSB

Offset Error 0.5 LSB

Gain Error ±5

%FSR

Gain Temperature Coefficient 90

ppm/ °C

VDD/2 Sampling Error ±2 ±7%

DYNAMIC PERFORMANCE (25kHz sinewave input, VIN = V

REF(p-p

), f

SCLK

= 5MHz, f

SAMPLE

= 100ksps, RIN = 100Ω)

Signal-to-Noise Plus Distortion

SINAD

48 dB

Total Harmonic Distortion
(up to the 5th Harmonic)

THD -69 dB

Spurious-Free Dynamic Range SFDR 66 dB

Small-Signal Bandwidth f

-3dB

4

MHz

ANALOG INPUT

Input Voltage Range 0

V

REF

V

Input Leakage Current VCH = 0 or V

DD

±0.7

±10 µA

Input Capacitance C

IN

18 pF

INTERNAL REFERENCE

MAX1115

2.048

Voltage V

REF

MAX1116

4.096

V

POWER REQUIREMENTS

MAX1115 2.7 5.5

Supply Voltage V

DD

MAX1116 4.5 5.5

V

f

SAMPLE

= 10ksps 14 21

MAX1115

f

SAMPLE

= 100ksps 135 190

f

SAMPLE

= 10ksps 19 25

MAX1116

f

SAMPLE

= 100ksps 182 230

Supply Current (Note 2) I

DD

Shutdown 0.8 10

µA

MAX1115/MAX1116

Single-Supply, Low-Power, Serial 8-Bit ADCs

_______________________________________________________________________________________ 3

Note 1: Relative accuracy is the deviation of the analog value at any code from its theoretical value after the full-scale range and off-

set have been calibrated.

Note 2: Input = 0 with logic input levels of 0 and V

DD

.

PARAMETER

SYMBOL

CONDITIONS

MIN

TYP

MAX

UNITS

Supply Rejection Ratio PSRR Full-scale or zero input

±0.5±1LSB/V

DIGITAL INPUTS (CNVST AND SCLK)

Input High Voltage V

IH

2V

Input Low Voltage V

IL

0.8 V

Input Hystersis

V

HYST

0.2 V

Input Current High I

IH

±10 µA

Input Current Low I

IL

±10 µA

Input Capacitance C

IN

2pF

DIGITAL OUTPUT (DOUT)

Output High Voltage V

OH

I

SOURCE

= 2mA VDD - 0.5 V

I

SINK

= 2mA 0.4

Output Low Voltage V

OL

I

SINK

= 4mA 0.8

V

Three-State Leakage Current I

L

±0.01

±10 µA

Three-State Output Capacitance

C

OUT

4pF

TIMING CHARACTERISTICS (Figures 6a–6d)

CNVST High Time t

csh

100

ns

CNVST Low Time t

csl

100

ns

Conversion Time t

conv

7.5 µs

Serial Clock High Time t

ch

75 ns

Serial Clock Low Time t

cl

75 ns

Serial Clock Period t

cp

200

ns

Falling of CNVST to DOUT
Active

t

csd

C

LOAD

= 100pF, Figure 1 100 ns

Serial Clock Falling Edge to
DOUT

t

cd

C

LOAD

= 100pF 10 100 ns

Serial Clock Rising Edge
To DOUT High-Z

t

chz

C

LOAD

= 100pF, Figure 2

100

500 ns

La st S er i al C l ock to N ex t C N V S T
( successi ve conver si ons on C H 0)

t

ccs

50 ns

ELECTRICAL CHARACTERISTICS (continued)

(VDD= +2.7V to +3.6V (MAX1115), VDD= +4.5V to +5.5V (MAX1116), TA= T

MIN

to T

MAX

, unless otherwise noted.)

MAX1115/MAX1116

Single-Supply, Low-Power, Serial 8-Bit ADCs

4 _______________________________________________________________________________________

Typical Operating Characteristics

(VDD= +3V (MAX1115), VDD= +5V (MAX1116), f

scu

= 5MHz, f

sample

= 100ksps, C

LOAD

= 100pF, TA = +25°C, unless otherwise

noted.)

-1.0

-0.4

-0.6

-0.8

-0.2

0

0.2

0.4

0.6

0.8

1.0

0 10050 150 200 250 300

INTEGRAL NONLINEARITY

vs. OUTPUT CODE

MAX1115 toc01

OUTPUT CODE

INL (LSB)

-0.2

-0.4

-0.6

0

0.2

0.4

0.6

0.8

1.0

0 10050 150 200 250 300

DIFFERENTIAL NONLINEARITY

vs. OUTPUT CODE

MAX1115 toc02

OUTPUT CODE

DNL (LSB)

-0.8

-1.0

0

0.2

0.1

0.4

0.3

0.6

0.5

0.7

SHUTDOWN SUPPLY CURRENT

vs. SUPPLY VOLTAGE

MAX1115 toc03

SUPPLY VOLTAGE (V)

SHUTDOWN CURRENT (µA)

2.5

3.5

4.5

5.5

100.0

0

0.01 0.1 1 10 100

SUPPLY CURRENT vs.

CONVERSION RATE

1.0

MAX1115 toc04

CONVERSION (ksps)

SUPPLY CURRENT (µA)

10.0

MAX1116
V

DD

= +5V

MAX1115
V

DD

= +3V

0

50

100

150

200

2.5 3.5 4.5 5.5

SUPPLY CURRENT

vs. SUPPLY VOLTAGE

MAX1115 toc05

SUPPLY VOLTAGE (V)

SUPPLY CURRENT (µA)

MAX1115

MAX1116

D

OUT

= 00000000

V

DD

= V

DIGITAL INPUTS

0

50

100

150

200

-40 -15 10 35 60 85

SUPPLY CURRENT

vs. TEMPERATURE

MAX1115 toc06

TEMPERATURE (°C)

SUPPLY CURRENT (µA)

D

OUT

= 00000000

V

DD

= V

REF

= V

DIGITAL INPUTS

MAX1115
V

DD

= +3V

MAX1116
V

DD

= +5V

5.0

5.2

5.3

5.1

5.4

5.5

2.5 3.5 4.5 5.5

CONVERSION TIME

vs. SUPPLY VOLTAGE

MAX1115 toc07

SUPPLY VOLTAGE (V)

CONVERSION TIME (µs)

MAX1115 toc08

5.0

5.2

5.3

5.1

5.4

5.5

-40 -15 10 35 60 85

CONVERSION TIME
vs. TEMPERATURE

TEMPERATURE (°C)

CONVERSION TIME (µs)

VDD = +3V

VDD = +5V

0

0.6

0.8

0.4

0.2

1.2

1.0

1.4

2.5 4.53.5 5.5

GAIN ERROR vs.

SUPPLY VOLTAGE

MAX1115 toc09

SUPPLY VOLTAGE (V)

GAIN ERROR (%FSR)

MAX1116
V

DD

= +5V

MAX1115
V

DD

= +3V