Analog Devices AD96687, AD96685 Datasheet

a

Ultrafast Comparators

AD96685/AD96687

FEATURES
Fast: 2.5 ns Propagation Delay
Low Power: 118 mW per Comparator
Packages: DIP, TO-100, SOIC, PLCC
Power Supplies: +5 V, –5.2 V
Logic Compatibility: ECL
MIL-STD-883 Versions Available
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 common­mode range from –2.5 V to +5 V. Outputs are complementary
digital signals fully compatible with ECL 10 K and 10 KH logic

AD96685 FUNCTIONAL BLOCK DIAGRAM

AD96687 FUNCTIONAL BLOCK DIAGRAM

families. The outputs provide sufficient drive current to directly
drive transmission lines terminated in 50 Ω to –2 V. A level sen­sitive latch input is included which permits tracking, track-hold,
or sample-hold modes of operation.

The AD96685 and AD96687 are available in both industrial,
–25°C to +85°C, and military temperature ranges. Industrial
range devices are available in 16-pin DIP, SOIC, and 20-lead
PLCC; additionally, the AD96685 is available in a 10-pin,
TO-100 metal can.

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AD96685/AD96687–SPECIFICATIONS

ABSOLUTE MAXIMUM RATINGS

Positive Supply Voltage (+VS) . . . . . . . . . . . . . . . . . . . . +6.5 V

Negative Supply Voltage (–V
Input Voltage Range

2

. . . . . . . . . . . . . . . . . . . . . . . . . . . . ±5 V

) . . . . . . . . . . . . . . . . . . . –6.5 V

S

Differential Input Voltage . . . . . . . . . . . . . . . . . . . . . . . . 5.5 V

Latch Enable Voltage . . . . . . . . . . . . . . . . . . . . . . . . –V

Output Current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 mA

Operating Temperature Range

AD96685/87/BH/BQ/BP/BR . . . . . . . . . . . .–25°C to +85°C

AD96685/87/TQ . . . . . . . . . . . . . . . . . . . .–55°C to +125°C

Storage Temperature Range . . . . . . . . . . . . .–55°C to +150°C

Junction Temperature . . . . . . . . . . . . . . . . . . . . . . . . . +175°C

Lead Soldering Temperature (10 sec) . . . . . . . . . . . . . +300°C

1

EXPLANATION OF TEST LEVELS

Test Level
I – 100% production tested.

II – 100% production tested at +25°C, and sample tested at

specified temperatures.

to 0 V

S

3

III – Sample tested only.
IV – Parameter is guaranteed by design and characterization

testing.
V – Parameter is a typical value only.
VI – All devices are 100% production tested at +25°C; 100%

production tested at temperature extremes for extended

temperature devices; sample tested at temperature ex-

tremes for commercial/industrial devices.

ELECTRICAL CHARACTERISTICS

Parameter Temp Level Min Typ Max Min Typ Max Min Typ Max Min Typ Max Units

INPUT CHARACTERISTICS

Input Offset Voltage
Input Offset Drift Full V 20 20 20 20 µV/°C

Input Bias Current +25°CI 710710710710µA
Input Offset Current +25°C I 0.1 1.0 0.1 1.0 0.1 1.0 0.1 1.0 µA
Input Resistance +25°C V 200 200 200 200 kΩ

Input Capacitance +25°CV2 222pF
Input Voltage Ranges Full VI –2.5 +5.0 –2.5 +5.0 –2.5 +5.0 –2.5 +5.0 V
Common-Mode Rejection Ratio Full VI 80 90 80 90 80 90 80 90 dB

ENABLE INPUT

Logic “1” Voltage Full VI –1.1 –1.1 –1.1 –1.1 V
Logic “0” Voltage Full VI –1.5 –1.5 –1.5 –1.5 V
Logic “1” Current Full VI 40 40 40 40 µA
Logic “0” Current Full VI 5555µA

DIGITAL OUTPUTS

Logic “1” Voltage Full VI –1.1 –1.1 –1.1 –1.1 V
Logic “0” Voltage Full VI –1.5 –1.5 –1.5 –1.5 V

SWITCHING PERFORMANCES

Propagation Delays

Input to Output HIGH +25°C IV 2.5 3.5 2.5 3.5 2.5 3.5 2.5 3.5 ns
Input to Output LOW +25°C IV 2.5 3.5 2.5 3.5 2.5 3.5 2.5 3.5 ns
Latch Enable to Output HIGH +25°C IV 2.5 3.5 2.5 3.5 2.5 3.5 2.5 3.5 ns

Latch Enable to Output LOW +25°C IV 2.5 3.5 2.5 3.5 2.5 3.5 2.5 3.5 ns
Dispersions
Latch Enable

Minimum Pulse Width +25°C IV 2.0 3.0 2.0 3.0 2.0 3.0 2.0 3.0 ns

Minimum Setup Time +25°C IV 0.5 1.0 0.5 1.0 0.5 1.0 0.5 1.0 ns

Minimum Hold Time +25°C IV 0.5 1.0 0.5 1.0 0.5 1.0 0.5 1.0 ns

POWER SUPPLY

Positive Supply Current (+5.0 V) Full VI 8 9 15 18 8 9 15 18 mA
Negative Supply Current (–5.2 V) Full VI 15 18 31 36 15 18 31 36 mA

Power Supply Rejection Ratio10Full VI 60 70 60 70 60 70 60 70 dB

NOTES

1

Absolute maximum ratings are limiting values, may be applied individually, and beyond which serviceability

of the circuit may be impaired. Functional operation under any of these conditions is not necessarily implied.
Exposure to absolute maximum rating conditions for extended periods may affect device reliability.

2

Under no circumstances should the input voltages exceed the supply voltages .

3

Typical thermal impedances . . .

AD96685 Metal Can θ
AD96685 Ceramic θ
AD96685 SOIC θ
AD96685 PLCC θ
AD96687 Ceramic θ
AD96687 SOIC θ
AD96687 PLCC θ

4

+25°CI 1 2 12 12 12 mV
Full VI 3333mV

Full VI 13 13 16 16 µA
Full VI 1.2 1.2 1.2 1.2 µA

6

7

8

9

= 172°C/W; θJC = 52°C/W

JA

= 115°C/W; θJC = 57°C/W

JA

= 170°C/W; θJC = 60°C/W

JA

= 88°C/W; θJC = 45°C/W

JA

= 115°C/W; θJC = 57°C/W

JA

= 92°C/W; θJC = 47°C/W

JA

= 81°C/W; θJC = 45°C/W

JA

+25°C V 50 50 50 50 ps

(Positive Supply Voltage = +5.0 V; Negative Supply Voltage = –5.2 V, unless otherwise noted)

Test AD96685BH/BQ/BP/BR AD96687BQ/BP/BR AD96685TQ AD96687TQ

Industrial Temp. Range –258C to +858C Military Temp. Range –558C to +1258C

4

RS = 100 Ω.

5

Input Voltage Range can be extended to –3.3 V if –VS = –6.0 V.

6

Outputs terminated through 50 Ω to –2.0 V.

7

Propagation delays measured with 100 mV pulse (10 mV overdrive), to

50% transition point of the output.

8

Change in propagation Delay from 100 mV to 1 V input overdrive.

9

Supply voltages should remain stable within ±5% for normal operation.

10

Measured at ±5% of +VS and –VS.

Specifications subject to change without notice.

–2–

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