1
SY88953L
Micrel
3.3V 10.7Gbps CML LIMITING POST
AMPLIFIER W/ TTL SD AND /SD
SY88953L
Rev.: A
Amendment: /0
Issue Date:
March 2003
TYPICAL APPLICATIONS CIRCUIT
APPLICATIONS
s
OC-192 SDH/SONET
s
10G Ethernet/Fibre Channel receivers
s
Upto 10.7Gbps proprietary link
s
XFP transceivers
s
Line driver/receiver
s
Single 3.3V power supply
s
Up to 10.7Gbps operation
s
800mVp-p output swing with 30ps edge rates
s
28dB voltage gain with 5mVp-p input sensitivity
s
On chip 50
I/O termination
s
Programmable signal detect (SD and /SD) with 6dB
hysteresis
s
Chatter-free OC-TTL SD and /SD outputs with internal
5k
pull-up resistors can feedback to TTL enable
(/EN) input
s
Available in a tiny (3mm
3mm) 16-pin MLFTM
package or die
FEATURES
DESCRIPTION
The SY88953L high-speed limiting post amplifier is
designed for use in fiber-optic receivers. The device connects
to typical transimpedance amplifiers (TIAs). The linear signal
output from TIAs can contain significant amounts of noise
and may vary in amplitude over time. The SY88953L quantizes
these signals and outputs CML level waveforms.
The SY88953L operates from a single +3.3V power supply,
over temperatures ranging from 40
C to +85
C. With its
wide bandwidth and high gain, signals with data rates up to
10.7Gbps and as small as 5mVp-p can be amplified to drive
devices with CML inputs.
The SY88953L outputs TTL signal-detect (SD and /SD)
signals. A programmable signal-detect level set pin (SD
LVL
)
sets the sensitivity of the input amplitude detection. SD asserts
high if the input amplitude rises above the threshold set by
SD
LVL
and deasserts low otherwise. /SD is the complementary
output of SD. /SD can be fedback to the enable (/EN) input
to maintain output stability under a loss of signal condition.
/EN deasserts the true output signal without removing the
input signal. Typically 6dB SD hysteresis is provided to
prevent chattering.
The SY88953L also includes an input threshold
adjustment to correct pulsewidth distortion.
SD
V
CC
/EN
GND
To
CDR
SY88953L
200k
From
Transimpedance
Amp.
D
OUT
/D
OUT
V
CC
SD
LVL
D
IN
/D
IN
0.1
F
0.1
F
0.1
F
0.1
F
/SD
V
THP
V
THN
Micro
LeadFrame and MLF are trademarks of Amkor Technology, Inc.
2
SY88953L
Micrel
PACKAGE/ORDERING INFORMATION
Ordering Information
Package
Operating
Package
Part Number
Type
Range
Marking
SY88953LMI
MLF-16
Industrial
953L
SY88953LXI
DIE
Industrial
--
PIN DESCRIPTION
Pin Number
Pin Name
Type
Pin Function
1
DIN
Data Input
True data input w/50
resistor to V
CC
.
2, 3, 10, 11
VCC
Power Supply
Positive power supply.
4
/DIN
Data Input
Complementary data input w/50
resistor to V
CC
.
5
VTHN
Input
/DIN DC threshold adjustment pin.
6
SD
Open-collector
Signal-Detect: Asserts high when the data input amplitude rises
TTL output w/
above the threshold set by SD
LVL
.
internal 5k
pull-up resistor
7
/SD
Open-collector
Inverted Signal-Detect: Asserts low when the data input amplitude
TTL output w/
rises above the threshold set by SD
LVL
.
internal 5k
pull-up resistor
8, 13, EP
GND
Ground
Device ground. Exposed pad must be soldered to PCB ground for
proper electrical and thermal performance.
9
/DOUT
CML Output
Complementary data output.
12
DOUT
CML Output
True data output.
14
SDLVL
Input
Signal-Detect Level Set: A resistor from this pin to V
CC
sets the
threshold for the data input amplitude at which SD will be asserted.
15
/EN
TTL Input:
Enable: Deasserts true data output when high.
Default is high.
16
VTHP
Input
DIN DC threshold adjustement pin.
1
2
3
4
12
11
10
9
16 15 14 13
5
6
7
8
DIN
VCC
VCC
/DIN
DOUT
VCC
VCC
/DOUT
GND
SDL
VL
/EN
VTHP
GND
/SD
SD
VTHN
16-Pin MLFTM
3
SY88953L
Micrel
Absolute Maximum Ratings
(Note 1)
Supply Voltage (V
CC
) ................................... -0.5V to +4.0V
Data Input Voltage (D
IN
,
/D
IN
) ... (V
CC
1.0V) to (V
CC
+0.5V)
Data Output Voltage (D
OUT
,
/D
OUT
) ....................................
.......................................... (V
CC
1.0V) to (V
CC
+0.5V)
Data Output Current (D
OUT,
/D
OUT
) ........................... 22mA
/EN Voltage ............................................................ 0 to V
CC
SD, /SD Current ........................................................... 5mA
SDLVL Voltage ...................................... (V
CC
1.3V) to V
CC
Storage Temperature (T
S
) ....................... 65
C to +150
C
Operating Ratings
(Note 2)
Supply Voltage (V
CC
) .................................. +3.0V to +3.6V
Ambient Temperature (T
A
) ......................... 40
C to +85
C
Junction Temperature (T
J
) ....................... 40
C to +120
C
Package Thermal Resistance
(Note 3)
MLFTM
(
JA
) Still-Air ..................................................... 59
C/W
(
JB
) Still-Air .................................................... 32
C/W
V
CC
= 3.0V to 3.6V; R
LOAD
= 50
to V
CC
; T
A
= 40
C to +85
C; typical values at V
CC
= 3.3V, T
A
= 25
C
Symbol
Parameter
Condition
Min
Typ
Max
Units
I
CC
Power Supply Current
no output load
110
170
mA
V
SDLVL
SDLVL
Voltage
V
CC
1.3
V
CC
V
V
IH
/EN Input HIGH Voltage
2.0
V
V
IL
/EN Input LOW Voltage
0.8
V
I
IH
/EN Input HIGH Current
V
IN
= V
CC
20
A
I
IL
/EN Input LOW Current
V
IN
= 0.5V
0.3
mA
V
OH
SD, /SD Output HIGH Level
2.4
V
V
OL
SD, /SD Output LOW Level
I
OL
= +2mA
0.5
V
V
OH
Output HIGH Voltage
50
to V
CC
output load
V
CC
0.020 V
CC
0.005
V
CC
V
V
OL
Output LOW Voltage
50
to V
CC
output load
V
CC
0.560 V
CC
0.400 V
CC
0.240
V
V
OFFSET
Differential Output Offset
80
mV
Z
O
Single-Ended Output Impedance
40
50
60
Z
O
Single-Ended Input Impedance
40
50
60
Note 1.
Specifications for packaged product only.
DC ELECTRICAL CHARACTERISTICS
(Note 1)
Note 1.
Permanent device damage may occur if ABSOLUTE MAXIMUM RATINGS are exceeded. This is a stress rating only and functional operation is
not implied at conditions other than those detailed in the operational sections of this data sheet. Exposure to ABSOLUTE MAXIMUM RATlNG
conditions for extended periods may affect device reliability.
Note 2.
The data sheet limits are not guaranteed if the device is operated beyond the operating ratings.
Note 3.
Exposed pad must be soldrered to PCB's ground plane.
4
SY88953L
Micrel
V
CC
= 3.0V to 3.6V; R
LOAD
= 50
to V
CC
; T
A
= 40
C to +85
C; typical values at V
CC
= 3.3V, T
A
= 25
C
Symbol
Parameter
Condition
Min
Typ
Max
Units
HYS
SD Hysteresis
electrical signal
2
6
8
dB
PSRR
Power Supply Rejection Ratio
35
dB
t
OFF
SD, /SD Release Time
0.1
0.5
s
t
ON
SD, /SD Assert Time
0.2
0.5
s
t
r
,t
f
Output Rise/Fall Time
V
ID
50mVp-p
30
35
ps
V
ID
Differential Input Voltage Swing
5
1800
mVp-p
V
OD
Differential Output Voltage Swing
480
800
1120
mVp-p
V
SR
SD Sensitivity Range
5
50
mVp-p
A
V(Diff)
Differential Voltage Gain
22
28
dB
S
21
Single-Ended Small-Signal Gain
16
22
dB
B
3dB
3dB Bandwidth
7.5
GHz
Note 1.
Specifications for packaged product only.
AC ELECTRICAL CHARACTERISTICS
(Note 1)
5
SY88953L
Micrel
TYPICAL OPERATING CHARACTERISTICS
0
20
40
60
80
100
120
-1
-0.8
-0.6
-0.4
-0.2
0.0
INPUT (mVp-p)
SD
LVL
=V
CC
V
SD Assert and Deassert Levels
vs. SD
LVL
3.3V
T
A
= 25
C
10Gbps
Pattern 2
23
-1
Assert
Deassert
-300
-250
-200
-150
-100
-50
0
0
1.0
2.0
3.0
4.0
D
IN
OFFSET (V
CC
mV)
V
TH
(V)
D
IN
OFFSET vs. V
TH
TIME (20ps/div.)
(5mV/div
.
)
23.15ns
23ns
Example of Using V
TH
to Cancel Effect of Pulse Width Distortion
(3.3V, 27
C, 10Gbps)
30mVp-p Differential Input
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