Datasheet

ManualsBrandsMAXIM INTEGRATED ManualsLinear ICsLinear IC - Custom amplification Amplifier, Comparator, Reference PDIP 8

General Description

The MAX951–MAX954 feature combinations of a

micropower operational amplifier, comparator, and ref-

erence in an 8-pin package. In the MAX951 and

MAX952, the comparator’s inverting input is connected

to an internal 1.2V ±2% bandgap reference. The

MAX953 and MAX954 are offered without an internal

reference. The MAX951/MAX952 operate from a single

2.7V to 7V supply with a typical supply current of 7µA,

while the MAX953/MAX954 operate from 2.4V to 7V with

a 5µA typical supply current. Both the op amp and

comparator feature a common-mode input voltage

range that extends from the negative supply rail to with-

in 1.6V of the positive rail, as well as output stages that

swing Rail-to-Rail

The op amps in the MAX951/MAX953 are internally

compensated to be unity-gain stable, while the op

amps in the MAX952/MAX954 feature 125kHz typical

bandwidth, 66V/ms slew rate, and stability for gains of

10V/V or greater. These op amps have a unique output

stage that enables them to operate with an ultra-low

supply current while maintaining linearity under loaded

conditions. In addition, they have been designed to

exhibit good DC characteristics over their entire operat-

ing temperature range, minimizing input-referred errors.

The comparator output stage of these devices continu-

ously sources as much as 40mA. The comparators

eliminate power-supply glitches that commonly occur

when changing logic states, minimizing parasitic feed-

back and making the devices easier to use. In addition,

they contain ±3mV internal hysteresis to ensure clean

output switching, even with slow-moving input signals.

Applications

Instruments, Terminals, and Bar-Code Readers

Battery-Powered Systems

Automotive Keyless Entry

Low-Frequency, Local-Area Alarms/Detectors

Photodiode Preamps

Smart Cards

Infrared Receivers for Remote Controls

Smoke Detectors and Safety Sensors

Features

♦ Op Amp + Comparator + Reference in an 8-Pin

µMAX Package (MAX951/MAX952)

♦ 7µA Typical Supply Current

(Op Amp + Comparator + Reference)

♦ Comparator and Op Amp Input Range Includes

Ground

♦ Outputs Swing Rail-to-Rail

♦ 2.4V to 7V Supply Voltage Range

♦ Unity-Gain Stable and 125kHz Decompensated

≥ 10V/V Op Amp Options

♦ Internal 1.2V ±2% Bandgap Reference

♦ Internal Comparator Hysteresis

♦ Op Amp Capable of Driving up to 1000pF Load

MAX951–MAX954

Ultra-Low-Power, Single-Supply

Op Amp + Comparator + Reference

________________________________________________________________ Maxim Integrated Products 1

TOP VIEW

( ) ARE FOR MAX953/MAX954

COMPOUT

REF (COMPIN-)

COMPIN+

AMPIN+

AMPIN-

AMPOUT

MAX951

MAX952

MAX953

MAX954

DIP/SO/µMAX

Pin Configuration

19-0431; Rev 2; 8/01

Typical Operating Circuit and Ordering Information appear

at end of data sheet.

Selector Guide

Rail-to-Rail is a registered trademark of Nippon Motorola, Ltd.

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.

PART

INTERNAL

PRECISION

REFERENCE

OP AMP

GAIN

STABILITY

(V/V)

COMPARATOR

SUPPLY

CURRENT

(µA)

MAX951

Yes 1

Yes 7

MAX952

Yes 10

Yes 7

MAX953

No 1

Yes 5

MAX954

No 10

Yes 5

Summary of content (12 pages)

PAGE 1
9-0431; Rev 2; 8/01 Ultra-Low-Power, Single-Supply Op Amp + Comparator + Reference Features ♦ Op Amp + Comparator + Reference in an 8-Pin µMAX Package (MAX951/MAX952) ♦ 7µA Typical Supply Current (Op Amp + Comparator + Reference) ♦ Comparator and Op Amp Input Range Includes Ground ♦ Outputs Swing Rail-to-Rail ♦ 2.4V to 7V Supply Voltage Range ♦ Unity-Gain Stable and 125kHz Decompensated AV ≥ 10V/V Op Amp Options ♦ Internal 1.
PAGE 2
MAX951–MAX954 Ultra-Low-Power, Single-Supply Op Amp + Comparator + Reference ABSOLUTE MAXIMUM RATINGS Supply Voltage (VDD to VSS) ....................................................9V Inputs Current (AMPIN_, COMPIN_)..........................................20mA Voltage (AMPIN_, COMPIN_).......(VDD + 0.3V) to (VSS - 0.3V) Outputs Current (AMPOUT, COMPOUT)......................................50mA Current (REF) ..................................................................
PAGE 3
Ultra-Low-Power, Single-Supply Op Amp + Comparator + Reference (VDD = 2.8V to 7V for MAX951/MAX952, VDD = 2.4V to 7V for MAX953/MAX954, VSS = 0, VCM COMP = 0 for the MAX953/MAX954, VCM OPAMP = 0, AMPOUT = (VDD + VSS)/2, COMPOUT = low, TA = TMIN to TMAX, typical values are at TA = +25°C, unless otherwise noted.) PARAMETER Power-Supply Rejection Ratio SYMBOL PSRR TYP MAX MAX951/MAX952, VDD = 2.8V to 7V CONDITIONS 0.05 1 MAX953/MAX954, VDD = 2.4V to 7V 0.
PAGE 4
MAX951–MAX954 Ultra-Low-Power, Single-Supply Op Amp + Comparator + Reference ELECTRICAL CHARACTERISTICS (continued) (VDD = 2.8V to 7V for MAX951/MAX952, VDD = 2.4V to 7V for MAX953/MAX954, VSS = 0, VCM COMP = 0 for the MAX953/MAX954, VCM OPAMP = 0, AMPOUT = (VDD + VSS)/2, COMPOUT = low, TA = TMIN to TMAX, typical values are at TA = +25°C, unless otherwise noted.
PAGE 5
Ultra-Low-Power, Single-Supply Op Amp + Comparator + Reference SUPPLY CURRENT vs. TEMPERATURE 5 MAX953/MAX954 4 3 VCM OPAMP = 0 AMPOUT = (VDD + VSS)/2 COMP- = 1.2V or REF COMP+ = 1.1V 6 5 MAX953/MAX954 4 3 VDD = 2.8V (MAX951/952), VDD = 2.4V (MAX953/954), VSS = 0, VCM OPAMP = 0 AMPOUT = 1/2 VDD, COMP- = 1.2V or REF COMP+ = 1.1V 2 1 0 0 -60 -40 -20 0 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 MAX951-954-toc03 1.190 VDD = 5V 1.185 1.
PAGE 6
Typical Operating Characteristics (continued) (TA = +25°C, unless otherwise noted.) OP AMP OUTPUT VOLTAGE vs. LOAD CURRENT 0.04 C B SINKING CURRENT 0.02 0.10 -0.02 SOURCING CURRENT -0.04 E D -0.06 F 1500 1000 SHORT TO VSS 500 0 SHORT TO VDD -500 NONINVERTING AMPIN+ = GND -0.08 NONINVERTING AMPIN+ = (VDD - VSS)/2 -0.10 -1000 1 10 100 LOAD CURRENT (µA) 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 1000 2000 SUPPLY VOLTAGE (V) OP AMP PERCENT OVERSHOOT vs.
PAGE 7
Ultra-Low-Power, Single-Supply Op Amp + Comparator + Reference COMPARATOR RESPONSE TIME FOR VARIOUS INPUT OVERDRIVES (RISING) MAX951-954 TOC15 COMPARATOR RESPONSE TIME FOR VARIOUS INPUT OVERDRIVES (FALLING) OUTPUT 1V/div MAX951-954 TOC16 INPUT 100mV/div 0 100mV OUTPUT 1V/div 20mV 10mV 50mV 10mV 20mV 50mV 0 INPUT 100mV/div 100mV 0 0 2µs/div 2µs/div MAX953: LOAD = 100kΩ || 100pF, VSUPPLY = 5V MAX953: LOAD = 100kΩ || 100pF, VSUPPLY = 5V MAX951/MAX953 OP AMP SMALL-SIGNAL TRANSIENT RESPONSE
PAGE 8
Ultra-Low-Power, Single-Supply Op Amp + Comparator + Reference MAX951–MAX954 Pin Description PIN NAME FUNCTION MAX951 MAX952 1 MAX953 MAX954 1 2 2 AMPIN- Inverting Op Amp Input 3 3 AMPIN+ Noninverting Op Amp Input 4 4 VSS Negative Supply or Ground 5 5 COMPIN+ 6 — REF — 6 COMPIN- 7 7 COMPOUT 8 8 VDD AMPOUT Op Amp Output Noninverting Comparator Input 1.200V Reference Output. Also connected to inverting comparator input.
PAGE 9
Ultra-Low-Power, Single-Supply Op Amp + Comparator + Reference RA R1 VS VIN COMPOUT COMPOUT RB REF REF Figure 2. External Hysteresis continuously source as much as 40mA. The comparators eliminate power-supply glitches that commonly occur when changing logic states, minimizing parasitic feedback and making them easier to use. In addition, they include internal hysteresis (±3mV) to ensure clean output switching, even with slow-moving input signals.
PAGE 10
MAX951–MAX954 Ultra-Low-Power, Single-Supply Op Amp + Comparator + Reference VCC = 5V ANTENNA AMPIN+ 0.1µF AMPOUT 0.1µF MAX952 10MΩ 20kΩ L1 330mH R2 C1A 390pF AMP C1B 330pF C1C 20pF to 60pF R1 2pF to 10pF Figure 3. Compensation for Feedback-Node Capacitance 7) Calculate RB. (R2) VS(H)  + VIHYST ( − VREF + ) (R2)(R A ) VIHSYT )(R A REF LAYOUT-SENSITIVE AREA, METAL RFI SHIELDING ADVISED Op Amp Stability and Board Layout Considerations In the example, RA is again 24kΩ.
PAGE 11
Ultra-Low-Power, Single-Supply Op Amp + Comparator + Reference 10kHz 5VP-P NEC SE307-C MAX953 NEC PH302B VCC R2 1.0MΩ,1% 0.1µF 30kΩ 51Ω R1A C1 49.9kΩ, 1% 150pF, 5% R1B 49.9kΩ, 1% 10MΩ AMP 100kΩ AMP COMP COMP 1.2V LAYOUT-SENSITIVE AREA 0.1µF MAX952 4.7MΩ RADIOACTIVE IONIZATION CHAMBER SMOKE SENSOR REF 5.1MΩ LAYOUT-SENSITIVE AREA 1 R1 x C1 = R2 x C2 = 2π fC Figure 5.
PAGE 12
MAX951–MAX954 Ultra-Low-Power, Single-Supply Op Amp + Comparator + Reference Chip Topography by the high-input-impedance op amp of a MAX951 (Figure 6). The comparator and resistor voltage divider set an alarm threshold to indicate a fire. Design and fabrication of the connection from the intermediate plate of the ionization chamber to the noninverting input of the op amp is critical, since the impedance of this node must be well above 50MΩ.