
AZ88943
High-Speed Limiting Post Amplifier
1630 S. STAPLEY DR., SUITE 125 • MESA, ARIZONA 85204 • USA • (480) 962-5881 • FAX (480) 890-2541
www.azmicrotek.com
ARIZONA MICROTEK, INC.
FEATURES
• Up to 2.5Gbps operation
• Differential PECL Inputs
• Differential PECL Outputs
• Open Drain TTL/CMOS SD Output
• TTL/CMOS Enable Input
• High-Speed SiGe Process
DESCRIPTION
The AZ88943 is a limiting post amplifier usable at data rates up to 2.5Gbps. It is ideal for use as a post
amplifier following a transimpedance amplifier.
The AZ88943 contains a programmable signal detect function to determine when the input signal is present.
This information can be used with the /EN input pin to disable the output under loss of signal conditions. The detect
threshold can be set with a resistor divider between V
CC
and V
REF
. The SD output is an open drain compatible with
CMOS and TTL.
The outputs produce standard PECL 100K voltage compensated levels.
BLOCK DIAGRAM
D
IN
/D
IN
D
OUT
/D
OUT
/EN
SD
SD
LVL
V
REF
PACKAGE AVAILABILITY
PACKAGE PART NO. MARKING
TSSOP 10 AZ88943T AZ88943
TSSOP 10 T&R AZ88943TR1 AZ88943
TSSOP 10 T&R AZ88943TR2 AZ88943
/EN
D
IN
/D
IN
SD
LVL
V
REF
V
CC
D
OUT
/D
OU
GND
1
3
2
4
5
TSSOP-10
10
8
9
7
6
SD
PIN DESCRIPTION
PIN FUNCTION
DIN, /DIN Differential Inputs
D
OUT
, /D
OUT
PECL Outputs
/EN Output Enable
SD
LVL
Signal Detect Threshold
SD SD Output
V
REF
Reference Voltage Output
VCC Positive Voltage
GND Ground
PINOUT ASSIGNMENT

AZ88943
February 2002 * REV - 0 www.azmicrotek.com
2
Absolute Maximum Ratings are those values beyond which device life may be impaired
Symbol Character Value Unit
VCC DC Supply Voltage (Referenced to GND) 4.5 V
TA Operating Temperature Range (In Free-Air) -40 to +85
°C
T
STG
Storage Temperature Range -65 to +125
°C
DIN, /DIN Input Voltage 0 to VCC V
/EN Input Voltage 0 to VCC V
LOS
LVL
Input Voltage 0 to VCC V
V
REF
Output Voltage VCC-2V to VCC V
D
OUT
, /D
OUT
Output Voltage VCC-2V to VCC V
DC Characteristics (V
CC
= 3.0V to 3.6V, R
LOAD
= 50Ω to VCC-2V)
-40°C 0°C 25°C 85°C
Symbol Characteristic
Min Max Min Max Min Typ Max Min Max
Unit
IEE Power Supply Current1 40 40 30 40 45 mA
VOH Output HIGH Voltage
V
CC
-
1085
VCC-
880
VCC1025
VCC-
880
VCC1025
VCC-
955
VCC-
880
VCC1025
VCC-
880
mV
VOL Output LOW Voltage
V
CC
-
1830
VCC1555
VCC1810
VCC1620
VCC1810
VCC1705
VCC1620
VCC1810
VCC1620
mV
VIH /EN Input HIGH Voltage 2.0 2.0 2.0 2.0 mV
VIL /EN Input LOW Voltage 0.8 0.8 0.8 0.8 mV
VOL SD Output LOW Voltage2 0.5 0.5 0.5 0.5 V
V
REF
Reference Voltage
V
CC
-
1.38
V
CC
-
1.26
V
CC
-
1.38
V
CC
-
1.26
V
CC
-
1.38
V
CC
-
1.26
V
CC
-
1.38
V
CC
-
1.26
V
IIH /EN Input HIGH Current 100 100 100 100
µA
V
CMR
Common Mode Range GND+2 VCC GND+2 VCC GND+2 VCC GND+2 VCC V
1. No output load.
2. I
OL
= +2mA.
AC Characteristics (V
CC
= 3.0V to 3.6V, R
LOAD
= 50Ω to VCC-2V)
-40°C 0°C 25°C 85°C
Symbol Characteristic
Min Max Min Max Min Typ Max Min Max
Unit
VID Input Voltage Range 5 1800 5 1800 5 1800 5 1800 mV
tr / tf Rise/Fall Time 150 150 150 150 ps
VOD
Diff V
ID
=15 mVp-p
Out V
ID
=5 mVp-p
600
200
MVp-p
HYS SD Hysteresis 2 8 2 8 2 4.6 8 2 8 dB
t
ONL
SD Release Time
Minimum Input
0.5 0.5 0.2 0.5 0.5
µs
t
ONH
SD Release Time
Maximum Input
0.5 0.5 0.2 0.5 0.5
µs
t
OFFL
SD Assert Time
0.5 0.5 0.1 0.5 0.5
µs
VSR SD Sensitivity Range 5 50 5 50 5 50 5 50 MVp-p

AZ88943
February 2002 * REV - 0 www.azmicrotek.com
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SD
V
CC
>
4.7kΩ
SD
LVL
V
REF
V
CC
R1
R2
SD OUTPUT
FROM
TRANSIMPEDANCE
AMPLIFIER
0.1µF
F0.1µ
D
IN
/D
IN
V
REF
F0.1µ
50Ω 50Ω
DIFFERENTIAL INPUT CONFIGURATION
SD
LVL
CIRCUIT
NOTES:
SD
LVL
= VCC – 1.32V +
R1 + R2 ≥ 2.6kΩ
R2 x 1.32V
R1 + R2

AZ88943
February 2002 * REV - 0 www.azmicrotek.com
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PACKAGE DIAGRAM
TSSOP 10
MILLIMETERS
DIM
MIN MAX
A
1.10
A1
0.05 0.15
A2
0.80 0.95
A3
0.25
bp
0.15 0.30
c
0.15 0.23
D1
2.90 3.10
E2
2.90 3.10
e
0.50
HE
4.80 5.00
L
0.95
Lp
0.40 0.70
v
0.10
w
0.10
y
0.10
Z
0.34 0.67
θ
0
O
6
O
OTES:
1. DIMENSIONS D AND E DO NOT
INCLUDE MOLD PROTRUSION.
2. MAXIMUM MOLD PROTRUSION
FOR D IS 0.15mm.
3. MAXIMUM MOLD PROTRUSION
FOR E IS 0.25mm.

AZ88943
February 2002 * REV - 0 www.azmicrotek.com
5
Arizona Microtek, Inc. reserves the right to change circuitry and specifications at any time without prior notice. Arizona Microtek, Inc.
makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does Arizona
Microtek, Inc. assume any liability arising out of the application or use of any product or circuit and specifically disclaims any and all
liability, including without limitation special, consequential or incidental damages. Arizona Microtek, Inc. does not convey any license
rights nor the rights of others. Arizona Microtek, Inc. products are not designed, intended or authorized for use as components in systems
intended to support or sustain life, or for any other application in which the failure of the Arizona Microtek, Inc. product could create a
situation where personal injury or death may occur. Should Buyer purchase or use Arizona Microtek, Inc. products for any such
unintended or unauthorized application, Buyer shall indemnify and hold Arizona Microtek, Inc. and its officers, employees, subsidiaries,
affiliates, and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out of, directly
or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim alleges tha
Arizona Microtek, Inc. was negligent regarding the design or manufacture of the part.