SY84113BU
Low Power 2.5V 1.25Gbps Limiting Post
Amplifier with Ultra Wide LOS Range
General Description
Features
The SY84113BU low power limiting post amplifier is
•
Ultra wide LOS Range (5mVpp to 100mVpp)
designed for use in fiber-optic optical modules for
•
Single 2.5V power supply
multirate applications up to 1.25Gbps. The device
•
Ultra low power consumption (55mW typ)
connects to a typical transimpedance amplifier (TIA) and
•
125Mbps to 1.25 Gbps operation
can produce output signals to CML-level waveforms.
•
Low-noise CML data outputs
Intended for the GbE and Fibre Channel applications,
the SY84113BU offers a wide LOS range. It is able to
•
TTL /EN input
detect input signals for as low as 5mVpp and as high as
•
Programmable LOS level (LOS
LVL
)
100mVpp. The SY84113BU is intended to be used in
•
Internal 50Ohm termination
AC-coupled input applications.
•
Available in a tiny 3mm x 3mm QFN package
The SY84113BU generates a Loss-of-Signal (LOS)
open-collector TTL output. A programmable Loss-of-
Signal level set pin (LOS
LVL
) sets the sensitivity of the
Applications
input amplitude detection. LOS asserts high if the input
•
Gigabit Ethernet
amplitude falls below the threshold set by LOS
LVL
and
de-asserts low otherwise. The enable input (/EN) de-
•
Fibre Channel
asserts the true output signal without removing the input
•
GEPON
signal. The LOS output can be fed back to the /EN input
to implement the squelch function that maintains output
Markets
stability under a loss-of-signal condition.
The SY84113BU operates on a single 2.5V power
•
Datacom/telecom
supply and offers ultra low power consumption. This
•
Compact SFP/SFF Optical transceiver
device is perfectly suited to meet the stringent power
•
SFP/SFF Optical transceiver
requirements of the CSFP/SFP/SFF optical modules.
All support documentation can be found on Micrel’s web
site at:
www.micrel.com.
_________________________________________________________________________________________________________
Typical Application
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (
408
) 944-0800 • fax + 1 (408) 474-1000 •
http://www.micrel.com
January 2011
M9999-011711-A
hbwhelp@micrel.com
or (408) 955-1690
Micrel, Inc.
SY84113BU
Ordering Information
Part Number
SY84113BUMG
SY84113BUMGTR
Notes:
1. Tape and Reel.
(1)
Package
Type
QFN-16
QFN-16
Operating
Range
Industrial
Industrial
Package Marking
113B with Pb-Free bar line indicator
113B with Pb-Free bar line indicator
Lead Finish
NiPdAu Pb-Free
NiPdAu Pb-Free
Pin Configuration
16-Pin (3mm x 3mm) QFN-16
Pin Description
Pin Number
15
Pin Name
/EN
Type
TTL Input
Pin Function
/Enable: This input enables the outputs when LOW. Internally
connected to a 25kΩ pull-up resistor and will default to a logic
HIGH state if left open.
Differential data inputs. Each input is internally terminated to the
VREF pin by a 50Ω resistor.
Reference Voltage: Place 0.1uF capacitor to Vcc to help
stabilize LOSLVL
DC Input
Loss-of-Signal Level Set. A resistor from this pin to V
CC
sets the
threshold for the data input amplitude at which LOS will be
asserted.
Device ground. Exposed pad must be connected to PCB
ground plane.
Loss-of-Signal: asserts high when the data input amplitude falls
below the threshold set by LOS
LVL
.
Differential data outputs. Unused output should be terminated
50Ω to VCC.
Positive power supply. . Bypass with a 0.1uF || 0.01uF low ESR
capacitor as close to VCC pin as possible.
1, 4
6
14
DIN, /DIN
VREF
LOSLVL
Data Input
2, 3, 10, 11,
EPAD
7
12, 9
5, 8, 13, 16
GND
LOS
/DOUT, DOUT
VCC
Ground
Open-collector TTL
output
CML Output
Positive Rail
January 2011
2
M9999-011711-A
hbwhelp@micrel.com
or (408) 955-1690
Micrel, Inc.
SY84113BU
Absolute Maximum Ratings
(1)
Supply Voltage (V
CC
) ....................................... 0V to +4.0V
Input Voltage (DIN, /DIN) .......................................0 to V
CC
Output Current (I
OUT
) ............................................... ±25mA
EN Voltage .............................................................0 to V
CC
V
REF
Current .......................................... -800µA to +500µA
LOS
LVL
Voltage................................................. V
REF
to V
CC
Lead Temperature (soldering, 20sec.) ..................... 260°C
Storage Temperature (T
s
) ....................... –65°C to +150°C
Operating Ratings(2)
Supply Voltage (V
CC
) ......................+2.375 to +2.625V
Ambient Temperature (T
A
).................. –40°C to +85°C
Junction Temperature (T
J
)................ –40°C to +120°C
Package Thermal Resistance
(3)
(θ
JA
) Still-air ............................................... 60°C/W
(ψ
JB
) ........................................................... 33°C/W
DC Electrical Characteristics
V
CC
= 2.5 ± 5%; T
A
= –40°C to +85°C, typical values at V
CC
= 2.5V, T
A
= 25°C.
Symbol
I
CC
LOS
LVL
V
OH
V
OL
V
REF
Z
0
Z
I
Parameter
Power Supply Current
LOS
LVL
Voltage
DOUT, /DOUT HIGH Voltage
DOUT, /DOUT LOW Voltage
Reference Voltage
Single-Ended Output Impedance
Single-Ended Input Impedance
40
40
Condition
Outputs terminated 50Ohm to Vcc
VREF
V
CC
-0.020 V
CC
-0.005
Vcc – 0.6
50
50
60
60
Min
Typ
22
Max
35
V
CC
V
CC
Units
mA
V
V
V
V
Ω
Ω
V
CC
-0.475 V
CC
-0.400 V
CC
-0.350
TTL DC Electrical Characteristics
V
CC
= 2.5 ± 5%; T
A
= –40°C to +85°C, typical values at V
CC
= 2.5V, T
A
= 25°C.
Symbol
V
IH
V
IL
I
IH
I
IL
V
OH
V
OL
Parameter
/EN Input HIGH Voltage
/EN Input LOW Voltage
/EN Input HIGH Current
/EN Input LOW Current
LOS Output HIGH Level
LOS Output LOW Level
Condition
Min
2.0
Typ
Max
Vcc
0.8
20
Units
V
V
µA
mA
V
V
IN
= V
CC
V
IN
= 0.5V
Vcc = 2.5V. IOH < 50uA
IOL = 2mA
-0.3
2
0.5
V
January 2011
3
M9999-011711-A
hbwhelp@micrel.com
or (408) 955-1690
Micrel, Inc.
SY84113BU
AC Electrical Characteristics
V
CC
= 2.5 ± 5%; T
A
= –40°C to +85°C, typical values at V
CC
= 2.5V, T
A
= 25°C.; R
Load
= 50Ω to V
CC
;
Symbol
t
r
, t
f
t
JITTER
V
ID
V
OD
T
OFF
T
ON
LOS
AL
LOS
DL
HYS
L
LOS
AM
LOS
DM
HYS
M
LOS
AH
LOS
DH
HYS
H
B
-3dB
A
V(Diff)
S
21
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 ratings 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. Package Thermal Resistance assumes exposed pad is soldered (or equivalent) to the devices most negative potential on the PCB.
ψ
JB
uses a
4-layer and
θ
JA
in still air unless otherwise stated.
4. Amplifier in limiting mode. Input is a 200MHz square wave.
5. Deterministic jitter measured using 1.250 Gbps K28.5 pattern, V
ID
= 60mV
PP
.
6. Random jitter measured using 1.250Gbps K28.7 pattern, V
ID
= 60mV
PP
.
7. See “Typical Operating Characteristics” for a graph showing how to choose a particular R
LOSLVL
for a particular LOS assert and its associated
de-assert amplitude.
8. This specification defines electrical hysteresis as 20log (LOS De-Assert/LOS Assert). The ratio between optical hysteresis and electrical
hysteresis is found to vary between 1.5 and 2 depending upon the level of received optical power and ROSA characteristics. Based on that
ratio, the optical hysteresis corresponding to the electrical hysteresis range 2dB-4.5 dB, shown in the AC characteristics table, will be 1dB-3dB
Optical Hysteresis.
9. In real world applications, the LOS Release/Assert time can be strongly influenced by the RC time constant of the AC-coupling cap and the
50Ω input termination. To keep this time low, use a decoupling cap with the lowest value that is allowed by the data rate and the number of
consecutive identical bits in the application (typical values are in the range of 0.001µF to 1.0µF).
Parameter
Output Rise/Fall Time
(20% to 80%)
Deterministic
Random
Differential Input Voltage Swing
Differential Output Voltage
Swing
LOS Release Time
LOS Assert Time
Low LOS Assert Level
Low LOS De-assert Level
Low LOS Hysteresis
Medium LOS Assert Level
Medium LOS De-assert Level
Medium LOS Hysteresis
High LOS Assert Level
High LOS De-assert Level
High LOS Hysteresis
3dB Bandwidth
Differential Voltage Gain
Single-Ended Small-Signal Gain
Condition
Note 4
Note 5
Note 6
Min
Typ
150
15
5
Max
260
Units
ps
ps
PP
ps
RMS
5
Note 4
Note 9
Note 9
R
LOSLVL
= 10kΩ, Note 7
R
LOSLVL
= 10kΩ, Note 7
R
LOSLVL
= 10kΩ, Note 8
R
LOSLVL
= 5kΩ, Note 7
R
LOSLVL
= 5kΩ, Note 7
R
LOSLVL
= 5kΩ, Note 8
R
LOSLVL
= 100Ω, Note 7
R
LOSLVL
= 100Ω, Note 7
R
LOSLVL
= 100Ω, Note 8
2
2
60
2
7
700
800
2
2
3.9
5.6
3.1
9.2
13.6
3.4
73
103
3.0
850
38
26
32
1800
950
10
10
mV
PP
mV
PP
uS
uS
mV
PP
mV
PP
4.5
16
4.5
130
4.5
dB
mV
PP
mV
PP
dB
mV
PP
mV
PP
dB
MHz
dB
dB
January 2011
4
M9999-011711-A
hbwhelp@micrel.com
or (408) 955-1690
Micrel, Inc.
SY84113BU
Typical Functional Characteristics
V
CC
= 2.5 ± 5%; T
A
= –40°C to +85°C, typical values at V
CC
= 2.5V, T
A
= 25°C.; R
Load
= 50Ω to V
CC
;
Typical Operating Characteristics
V
CC
= 2.5 ± 5%; T
A
= –40°C to +85°C, typical values at V
CC
= 2.5V, T
A
= 25°C.; R
Load
= 50Ω to V
CC
;
LOS Assert/De-Assert Levels
1000
6
5
Amplitude (mV)
100
Hysteresis (dB)
4
3
2
1
0.1
1
LOSLVL Resistor (KOhm)
10
1
0.1
1
LOSLVL Resistor (KOhm)
10
LOS Hysteresis
10
January 2011
5
M9999-011711-A
hbwhelp@micrel.com
or (408) 955-1690
