Datasheet

ManualsBrandsANALOG DEVICES ManualsLinear ICsLinear IC - Comparator + lock Complementary, ECL, Open emitter SOIC 16

REV. D

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reliable. However, no responsibility is assumed by Analog Devices for its

use, nor for any infringements of patents or other rights of third parties that

may result from its use. No license is granted by implication or otherwise

under any patent or patent rights of Analog Devices.

AD96685/AD96687

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.

Tel: 781/329-4700 www.analog.com

Fax: 781/326-8703 © Analog Devices, Inc., 2001

Ultrafast Comparators

AD96685 FUNCTIONAL BLOCK DIAGRAM

NONINVERTING

INPUT

INVERTING

INPUT

Q OUTPUT

LATCH

ENABLE

AD96687 FUNCTIONAL BLOCK DIAGRAM

NONINVERTING

INPUT

INVERTING

INPUT

Q OUTPUT

LATCH

ENABLE

NONINVERTING

INPUT

INVERTING

INPUT

Q OUTPUT

LATCH

ENABLE

THE OUTPUTS ARE OPEN EMITTERS, REQUIRING EXTERNAL

PULL-DOWN RESISTORS. THESE RESISTORS MAY BE IN THE

RANGE OF 50⍀-200⍀ CONNECTED TO –2.0V, OR 200⍀-2000⍀

FEATURES

Fast: 2.5 ns Propagation Delay

Low Power: 118 mW per Comparator

Packages: DIP, SOIC, PLCC

Power Supplies: +5 V, –5.2 V

Logic Compatibility: ECL

50 ps Delay Dispersion

APPLICATIONS

High Speed Triggers

High Speed Line Receivers

Threshold Detectors

Window Comparators

Peak Detectors

GENERAL DESCRIPTION

The AD96685 and AD96687 are ultrafast voltage comparators.

The AD96685 is a single comparator with 2.5 ns propagation

delay; the AD96687 is an equally fast dual comparator. Both

devices feature 50 ps propagation delay dispersion which is a

particularly important characteristic of high-speed comparators.

It is a measure of the difference in propagation delay under

differing overdrive conditions.

A fast, high precision differential input stage permits consistent

propagation delay with a wide variety of signals in the common-

mode range from –2.5 V to +5 V. Outputs are complementary

digital signals fully compatible with ECL 10 K and 10 KH logic

families. The outputs provide sufficient drive current to directly

drive transmission lines terminated in 50 Ω to –2 V. A level

sensitive latch input which permits tracking, track-hold, or

sample-hold modes of operation is included.

The AD96685 is available in industrial –25°C to +85°C range

in 16-pin SOIC.

The AD96687 is available in industrial range –25°C to +85°C,

in 16-pin DIP, SOIC, and 20-lead PLCC.

Summary of content (8 pages)

PAGE 1
a FEATURES Fast: 2.5 ns Propagation Delay Low Power: 118 mW per Comparator Packages: DIP, SOIC, PLCC Power Supplies: +5 V, –5.
PAGE 2
AD96685/AD96687–SPECIFICATIONS ELECTRICAL CHARACTERISTICS (Positive Supply Voltage = 5.0 V; Negative Supply Voltage = –5.2 V, unless otherwise noted.) Industrial Temperature Range –25ⴗC to +85ⴗC Temp Test Level 25°C Full Full 25°C Full 25°C Full 25°C 25°C Full Full I VI V I VI I VI V V VI VI ENABLE INPUT Logic “1” Voltage Logic “0” Voltage Logic “1” Current Logic “0” Current Full Full Full Full VI VI VI VI –1.1 DIGITAL OUTPUTS3 Logic “1” Voltage Logic “0” Voltage Full Full VI VI –1.
PAGE 3
AD96685/AD96687 ABSOLUTE MAXIMUM RATINGS 1 EXPLANATION OF TEST LEVELS Positive Supply Voltage (+VS) . . . . . . . . . . . . . . . . . . . . . 6.5 V Negative Supply Voltage (–VS) . . . . . . . . . . . . . . . . . . . –6.5 V Input Voltage Range2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . ± 5 V Differential Input Voltage . . . . . . . . . . . . . . . . . . . . . . . . 5.5 V Latch Enable Voltage . . . . . . . . . . . . . . . . . . . . . . . . –VS to 0 V Output Current . . . . . . . . . . . . . .
PAGE 4
AD96685/AD96687 PIN CONFIGURATIONS 3 14 NC 4 AD96685 13 NC TOP VIEW 5 (Not to Scale) 12 Q OUTPUT LATCH ENABLE 6 NC 7 VS– 8 11 Q OUTPUT 10 NC 9 NC NC = NO CONNECT GROUND LATCH ENABLE NC LATCH ENABLE VS– Q OUTPUT 15 NC Q OUTPUT 16 GROUND 2 2 Q OUTPUT 1 NC VS+ NONINVERTING INPUT INVERTING INPUT NC AD96687BQ/BR Q OUTPUT GROUND 1 1 AD96687BP Q OUTPUT AD96685BR 3 2 1 20 19 3 18 4 17 5 AD96687 6 TOP VIEW (Not to Scale) 7 15 14 8 9 10 11 12 Q OUTPUT 15 Q OUTPUT GROUND
PAGE 5
Typical Performance Characteristics–AD96685/AD96687 APPLICATIONS INFORMATION The AD96685/AD96687 comparators are very high speed devices. Consequently, high speed design techniques must be employed to achieve the best performance. The most critical aspect of any AD96685/AD96687 design is the use of a low impedance ground plane. Another area of particular importance is power supply decoupling. Normally, both power supply connections should be separately decoupled to ground through 0.1 µF ceramic and 0.
PAGE 6
AD96685/AD96687 Typical Applications +VREF AD96685/ AD96687 50⍀ VIN AD96685/ AD96687 VIN OUTPUTS VREF 50⍀ 50⍀ 50⍀ 50⍀ 50⍀ 50⍀ –VREF LATCH ENABLE INPUT OUTPUT 50⍀ 50⍀ 50⍀ 50⍀ –2V –2V Figure 2. High Speed Sampling Circuit Figure 3. High Speed Window Comparator –6– REV.
PAGE 7
AD96685/AD96687 OUTLINE DIMENSIONS Dimensions shown in inches and (mm). 16-Lead Ceramic DIP 0.005 (0.13) MIN 16-Lead SOIC 0.098 (2.49) MAX 16 9 PIN 1 1 8 0.840 (21.34) MAX 0.200 (5.08) MAX 0.394 (10.00) 0.385 (9.78) 0.310 (7.87) 0.220 (5.59) 0.158 (4.00) 0.150 (3.80) 0.320 (8.13) 0.290 (7.37) 0.060 (1.52) 0.015 (0.38) 0.150 (3.81) 0.200 (5.08) MIN 0.125 (3.18) SEATING 0.023 (0.58) 0.100 0.070 (1.78) PLANE 0.014 (0.36) (2.54) 0.030 (0.76) BSC PIN 1 0.015 (0.38) 0.008 (0.20) 15° 0° 0.310 (7.
PAGE 8
–8– PRINTED IN U.S.A.