SY88913 Datasheet, PDF (1/8 Pages) Micrel Semiconductor – 1.25Gbps HIGH-SPEED LIMITING POST AMPLIFIER

1.25Gbps HIGH-SPEED
LIMITING POST AMPLIFIER
SY88913
FEATURES
s Up to 1.25Gbps operation
s Low noise
s Chatter-Free /LOS Generation
s PECL /LOS Output
s TTL /EN Input
s Differential PECL inputs for data
s /EN input is TTL with internal 27K pull up
s Single power supply
s Designed for use with SY88902 and SY88904
s Available in a tiny 10-pin (3mm) MSOP
PIN CONFIGURATION
/EN 1
DIN 2
/DIN 3
VREF 4
LOSLVL 5
MSOP
K10-1
10 VCC
9 DOUT
8 /DOUT
7 /LOS
6 GND
DESCRIPTION
The SY88913 limiting post amplifier with its high gain
and wide bandwidth is ideal for use as a post amplifier in
fiber-optic receivers with data rates up to 1.25Gbps.
Signals as small as 5mVp-p can be amplified to drive
devices with PECL inputs. The SY88913 generates a
chatter-free PECL Loss of Signal (/LOS).
The SY88913 incorporates a programmble level detect
function to identify when the input signal has been lost.
This information can be fed back to the /EN input of the
device to maintain stability under loss of signal conditions.
Using LOSLVL pin the sensitivity of the level detect can
be adjusted. The LOSLVL voltage can be set by
connecting a resistor divider between VCC and VREF,
Figure 2. Figure 3 shows the relationship between input
level sensitivity and the voltage set on LOSLVL. Figure 4
shows the relationship between input level sensitivity and
resistor divider ratio.
APPLICATIONS
s 1.25Gbps Gigabit Ethernet
s 531Mbps and 1062Mbps Fibre Channel
s 622Mbps SONET
s Gigabit Interface Converter
BLOCK DIAGRAM
DIN
DIN
VREF
VCC
GND
LOSLVL
Limiting
Amplifier
ECL
Buffer
Level
Detect
1
Enable
DOUT
DOUT
EN
LOS
Rev.: E Amendment: /1
Issue Date: July 2000