Micrel, Inc.
3.3V/5V 3.2Gbps CML
LOW-POWER LIMITING
POST AMPLIFIER W/TTL LOS
DESCRIPTION
SY88973V
SY88973V
FEATURES
s
Multi-rate up to 3.2Gbps operation
s
Wide gain-bandwidth product
•
38dB differential gain
•
2GHz 3dB bandwidth
s
Low noise 50
Ω
CML data outputs
•
800mV
PP
output swing
•
60ps edge rates
•
5ps
RMS
typ. random jitter
•
15ps
PP
typ. deterministic jitter
s
Chatter-free, Loss-of-Signal (LOS) output
•
4.6dB electrical hysteresis
•
OC-TTL output with internal 4.75k
Ω
pull-up
resistor
Programmable LOS sensitivity using single external
resistor
Internal 50
Ω
data input termination
TTL /EN input allows feedback from LOS
Wide operating range
•
Single 3.3V
±
10% or 5V
±
10% power supply
•
–40
°
C to +85
°
C industrial temperature range
Available in tiny 10-pin EPAD-MSOP and
16-pin MLF™ packages
s
s
s
s
s
The SY88973V low-power, 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 SY88973V
quantizes these signals and outputs typically 800mV
PP
voltage-limited waveforms.
The SY88973V operates from a single +3.3V
±10%
or
+5V
±10%
power supply, over an industrial temperature
range of –40°C to +85°C. With its wide bandwidth and high
gain, signals with data rates up to 3.2Gbps and as small as
10mV
PP
can be amplified to drive devices with CML inputs
or AC-coupled PECL inputs.
The SY88973V incorporates a loss-of-signal (LOS), open-
collector TTL output with internal 4.75kΩ pull-up resistor. A
programmable, loss-of-signal level set pin (LOSLVL) sets
the sensitivity of the input amplitude detection. LOS asserts
high if the input amplitude falls below the threshold set by
LOSLVL and de-asserts low otherwise. LOS can be fed
back to the enable (/EN) input to maintain output stability
under a loss-of-signal condition. /EN de-asserts the true
output signal without removing the input signal. Typically
4.6dB LOS hysteresis is provided to prevent chattering.
Please see Micrel’s website at www.micrel.com for a
complete selection of optical module ICs. The following table
summarizes the differences between devices in Micrel’s
latest family of Limiting Amplifiers.
All support documentation can be found on Micrel’s web
site at www.micrel.com.
Integrated 50
Ω
Part Number Input Termination
SY88773V
SY88823V
SY88843V
SY88973V
No
No
Yes
Yes
LOS
or SD
LOS
SD
SD
LOS
Active LOW
or HIGH Enable
LOW
HIGH
HIGH
LOW
APPLICATIONS
s
1.25Gbps and 2.5Gbps Gigabit Ethernet
s
1.062Mbps and 2.125Gbps Fibre Channel
s
155Mbps, 622Gbps, 1.25Gbps, and 2.5Gbps SONET/
SDH
s
Gigabit interface converter (GBIC)
s
Small form factor (SFF) and small form factor
pluggable (SFP) transceivers
s
Parallel 10G Ethernet
s
High-gain line driver and line receiver
Table 1. Limiting Amplifiers Selection Guide
TYPICAL PERFORMANCE
3.3V, 25°C, 10mV
pp
Input
@3.2Gbps 2
31
–1 PRBS, R
LOAD
= 50Ω to V
CC
Output Swing
(75mV/div.)
MicroLeadFrame
and MLF are trademarks of Amkor Technology, Inc.
M9999-110905
hbwhelp@micrel.com or (408) 955-1690
TIME (50ps/div.)
Rev.: C
Amendment: /0
1
Issue Date: November 2005
Micrel, Inc.
SY88973V
FUNCTIONAL BLOCK DIAGRAM
VCC
DIN
50Ω
/DIN
REF
REF
Generator
Level
Detect
2.8k
Ω
TTL
Buffer
Limiting
Amplifer
CML
Buffer
DOUT
/DOUT
VCC
25k
Ω
/EN
VCC
4.75k
Ω
OC-TTL
Buffer
LOS
LOSLVL
GND
M9999-110905
hbwhelp@micrel.com or (408) 955-1690
2
Micrel, Inc.
SY88973V
PACKAGE/ORDERING INFORMATION
LOSLVL
VCC
VCC
Ordering Information
(1)
Part Number
12
11
10
9
/EN
16
15
14
13
Package
Type
K10-2
K10-2
MLF-16
MLF-16
K10-2
K10-2
MLF-16
MLF-16
Operating
Range
Industrial
Industrial
Industrial
Industrial
Industrial
Industrial
Industrial
Industrial
Package
Marking
973V
973V
973V
973V
973V with
Pb-Free bar-line indicator
973V with
Pb-Free bar-line indicator
973V with
Pb-Free bar-line indicator
973V with
Pb-Free bar-line indicator
Lead
Finish
Sn-Pb
Sn-Pb
Sn-Pb
Sn-Pb
Pb-Free
Matte-Sn
Pb-Free
Matte-Sn
Pb-Free
NiPdAu
Pb-Free
NiPdAu
DIN
GND
GND
/DIN
1
2
3
4
5
6
7
8
/DOUT
GND
GND
/DOUT
SY88973VKI
SY88973VKITR
(2)
SY88973VMI
SY88973VMITR
(2)
SY88973VEY
(3)
SY88973VEYTR
(2, 3)
SY88973VMG
(3)
SY88973VMGTR
(2, 3)
VCC
REF
16-Pin MLF™ (MLF-16)
/EN 1
DIN 2
/DIN 3
REF 4
LOSLVL 5
VCC
10 VCC
9 DOUT
8 /DOUT
7 LOS
6 GND
LOS
Notes:
1. Contact factory for die availability. Dice are guaranteed at T
A
= 25°C, DC Electricals only.
2. Tape and Reel.
3. Pb-Free package is recommended for new designs.
10-Pin EPAD-MSOP (K10-2)
PIN DESCRIPTION
Pin Number
(MSOP)
1
2, 3
4
5
Pin Number
(MLF™)
15
1, 4
6
14
Pin Name
/EN
DIN, /DIN
REF
LOSLVL
Type
TTL Input:
Default is high.
Differential
Data Input
Pin Function
Enable: De-asserts true data output when high.
Incorporates 25kΩ pull-up to VCC.
Differential data input. Each pin internally terminates to
REF through 50Ω.
Reference Voltage: Bypass with 0.01µF low ESR capacitor
from REF to VCC to stabilize LOSLVL and REF.
Input:
Default is
maximum sensitivity.
Ground
Open Collector
TTL Output with
internal 4.75kΩ
pull-up resistor
Differential
CML Output
Power Supply
Loss-of-Signal level set: A resistor from this pin to VCC
sets the threshold for the data input amplitude at which the
LOS output will be asserted.
Device ground. Exposed pad must be soldered
(or equivalent) to the same potential as the ground pins.
Loss-of-Signal: asserts high when the data input amplitude
falls below the threshold set by LOSLVL.
6
Exposed Pad
7
2, 3, 10, 11
Exposed Pad
7
GND
LOS
8, 9
10
9, 12
5, 8, 13, 16
DOUT, /DOUT
VCC
Differential data output.
Positive power supply. Bypass with 0.1µF0.01µF low
ESR capacitors. 0.01µF capacitors should be as close as
possible to VCC pins.
M9999-110905
hbwhelp@micrel.com or (408) 955-1690
3
Micrel, Inc.
SY88973V
Absolute Maximum Ratings
(1)
Supply Voltage (V
CC
) ....................................... 0V to +7.0V
/EN, LOSLVL Voltage ............................................0 to V
CC
REF Current ...............................................................
±1mA
LOS Current ...............................................................
±5mA
DOUT, /DOUT Current .............................................
±25mA
DIN, /DIN Current .....................................................
±10mA
Storage Temperature (T
S
) ....................... –65°C to +150°C
Lead Temperature (Soldering, 20 sec.) .................... 260°C
Operating Ratings
(2)
Supply Voltage (V
CC
) .............................. +3.0V to +3.6V or
............................................................ +4.5V to +5.5V
Ambient Temperature (T
A
) ......................... –40°C to +85°C
Junction Temperature (T
J
) ....................... –40°C to +120°C
Package Thermal Resistance
(3)
MLF™
θ
JA
(Still-Air) ..................................................... 61°C/W
ψ
JB ...................................................................................
38°C/W
EPAD-MSOP
θ
JA
(Still-Air) ..................................................... 38°C/W
ψ
JB ...................................................................................
22°C/W
DC ELECTRICAL CHARACTERISTICS
V
CC
= 3.0V to 3.6V or 4.5V to 5.5V, T
A
= –40°C to +85°C; typical values at V
CC
= 3.3V, T
A
= 25°C.
Symbol
I
CC
Parameter
Power Supply Current
Power Supply Current
V
REF
V
LOSLVL
V
OH
V
OL
V
OFFSET
Z
O
Z
I
REF Voltage
LOSLVL Voltage Range
Output HIGH Voltage
Output LOW Voltage
Differential Output Offset
Single-Ended Output Impedance
Single-Ended Input Impedance
Note 6
3.3V,
Note 6
5V,
Note 6
Note 6
40
40
50
50
V
REF
V
CC
–0.020 V
CC
–0.005
Condition
3.3V,
Note 4
5V,
Note 4
3.3V,
Note 5
5V,
Note 5
Min
Typ
28
30
45
47
V
CC
–1.3
V
CC
V
CC
Max
42
45
62
65
Units
mA
mA
mA
mA
V
V
V
V
V
mV
Ω
Ω
V
CC
–0.475 V
CC
–0.400 V
CC
–0.350
V
CC
–0.510 V
CC
–0.400 V
CC
–0.350
±80
60
60
TTL DC ELECTRICAL CHARACTERISTICS
V
CC
= 3.0V to 3.6V or 4.5V to 5.5V, T
A
= –40°C to +85°C.
Symbol
V
OH
V
OL
V
IH
V
IL
I
IH
I
IL
Parameter
LOS Output HIGH Level
LOS Output LOW Level
/EN Input HIGH Voltage
/EN Input LOW Voltage
/EN Input HIGH Current
/EN Input LOW Current
V
IN
= 2.7V
V
IN
= V
CC
V
IN
= 0.5V
–0.3
Condition
Sourcing 100µA
Sinking 2mA
2.0
0.8
20
100
Min
2.4
Typ
Max
V
CC
0.5
Units
V
V
V
V
µA
µA
mA
Notes:
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 Rating conditions for
extended periods may affect device reliability.
2. The data sheet limits are not guaranteed if the device is operated beyond the operating ratings.
3. Thermal performance assumes the use of 4-layer PCB. Exposed pad must be soldered (or equivalent) to the device's most negative potential on the
PCB.
4. Excludes current of CML output stage. See “Detailed Description.”
5. Total device current with no output load.
6. Output levels are based on a 50Ω to V
CC
load impedance. If the load impedance is different, the output level will be changed. Amplifier is in limiting
mode.
M9999-110905
hbwhelp@micrel.com or (408) 955-1690
4
Micrel, Inc.
SY88973V
AC ELECTRICAL CHARACTERISTICS
V
CC
= 3.0V to 3.6V or 4.5V to 5.5V, T
A
= –40°C to +85°C, R
LOAD
= 50Ω to V
CC
; typical values at V
CC
= 3.3V, T
A
= 25°C.
Symbol
PSRR
t
r
,t
f
t
JITTER
V
ID
V
OD
HYS
t
OFF
t
ON
V
SR
B
–3dB
A
V(Diff)
S
21
Notes:
7. Amplifier in limiting mode. Input is a 200MHz square wave, t
r
< 300ps.
8. Deterministic jitter measured using 2.488Gbps K28.5 pattern, V
ID
= 10mV
PP
. Random jitter measured using 2.488Gbps K28.7 pattern, V
ID
= 10mV
PP
.
9. Electrical signal.
10. This is the detectable range of input amplitudes that can assert LOS. The input amplitude to deassert LOS is 2–8dB higher than the assert ampli-
tude. See “Typical Operating Characteristics” for graphs showing how to choose a particular V
LOSLVL
or R
LOSLVL
for a particular LOS assert, and its
associated de-assert, amplitude. If increased LOS sensitivity and hysteresis are required, an application note entitled “Notes on Sensitivity and
Hysteresis in Micrel Post Amplifiers” is available at http://www.micrel.com/product-info/app_hints+notes.shtml.
Parameter
Power Supply Rejection Ratio
Output Rise/Fall Time
(20% to 80%)
Deterministic
Random
Differential Input Voltage Swing
Differential Output Voltage Swing
LOS Hysteresis
LOS Release Time
LOS Assert Time
LOS Sensitivity Range
–3dB Bandwidth
Differential Voltage Gain
Single-Ended Small-Signal Gain
Condition
Min
Typ
35
Max
Units
dB
Note 7
Note 8
10
3.3V,
Note 7
5V,
Note 7
Note 9
700
700
2
60
15
5
120
ps
ps
PP
ps
RMS
1800
800
800
4.6
0.1
0.2
950
1020
8
0.5
0.5
35
2.0
mV
PP
mV
PP
mV
PP
dB
µs
µs
mV
PP
GHz
dB
dB
Note 10
10
32
26
38
32
M9999-110905
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5
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