MAX3861 Datasheet, PDF (1/13 Pages) Maxim Integrated Products – 2.7Gbps Post Amp with Automatic Gain Control

19-2342; Rev 0; 02/02
EVALUATION ^KIT
AVAILABLE
2.7Gbps Post Amp with Automatic Gain Control
General Description
The MAX3861 is a low-power amplifier with automatic
gain control (AGC), designed for WDM transmission
systems employing optical amplifiers and requiring a
vertical threshold adjustment after the post amp.
Operating from a single 3.3V supply, this AGC amplifier
linearly amplifies/attenuates the input signal while main-
taining a fixed output-voltage swing at data rates up to
2.7Gbps. Both the input and output are on-chip termi-
nated to match 50Ω interfaces.
This amplifier has a small-signal bandwidth of 3.4GHz
and an input-referred noise of 0.26mV_RMS. Over an
input signal range of 6mV_P-P to 1200mV_P-P (46dB), the
MAX3861 delivers a constant output amplitude that is
adjustable from 400mV_P-P to 920mV_P-P. Variation in
output swing is controlled within 0.2dB over a 16dB
input range. The MAX3861 provides a received-signal-
strength indicator (RSSI) that is linear, within 2.5%, for
input signal levels up to 100mV_P-P and an input signal
detect (SD) with programmable threshold.
Applications
OC-48/STM-16 Transmission Systems
WDM Optical Receivers
Long Reach Optical Receivers
Continuous Rate Receivers
Typical Application Circuit
C_CD
0.1µF
MAXIM
2.7Gbps
TIA
C_CZ
0.22µF
50Ω
0.1µF
50Ω
0.1µF
CZ+ ^{CD+ CD-} CG+
CZ-
CG-
IN+
OUT+
IN- ^MAX3861 OUT-
R_TH
1.8kΩ
R_RSSI
50kΩ
TH
OSM
SD
VREF
RSSI
SC
EN
C_CG
2200pF
50Ω
MAXIM
MAX3873
CDR
50Ω
R_OSM
50kΩ
Features
o Single 3.3V Power Supply
o 72mA Supply Current
o 3.4GHz Small-Signal Bandwidth
o 0.26mV_RMS Input-Referred Noise
o 6mV_P-P to 1200mV_P-P Input Range (46dB)
o Input Signal Detect with Programmable Threshold
o RSSI (Linear Up to 100mV_P-P)
o Adjustable Output Amplitude
o 0.2dB Output Voltage Variation (Over 16dB Input
Signal Variation)
Ordering Information
PART
TEMP RANGE PIN-PACKAGE
MAX3861EGG
-40°C to +85°C 24 QFN*
MAX3861E/D
-40°C to +85°C Dice**
*EP = Exposed Pad
**Dice are designed to operate over a -40°C to +120°C junc-
tion temperature (TJ) range, but are tested and guaranteed at
TA = +25°C.
Pin Configuration
TOP VIEW
24 23 22 21 20 19
TH 1
V_{CC 2}
IN+ ₃
IN- 4
V_{CC 5}
EN 6
MAX3861
18 SD
17 V_CC
16 OUT+
15 OUT-
14 V_CC
13 OSM
7 8 9 10 11 12
CONTROLLED IMPEDANCE LINE
QFN-EP
________________________________________________________________ Maxim Integrated Products 1
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.