1
Precision Edge®
SY58012U
Micrel, Inc.
M9999-051408
hbwhelp@micrel.com or (408) 955-1690
DESCRIPTION
Precision 1:2, 800mV LVPECL fanout buffer
Guaranteed AC performance over temperature/
voltage:
> 5GHz fMAX (clock)
< 110ps tr/t
f times
< 260ps tpd
< 15ps max skew
Low jitter performance
< 10psPP total jitter (clock)
< 1psRMS random jitter (data)
< 10psPP deterministic jitter (data)
Accepts an input signal as low as 100mV
Unique input termination and VT pin accepts DC-
and AC-coupled differential inputs: LVPECL, LVDS,
and CML
Outputs are 100k LVPECL compatible, 800mV swing
Power supply 2.5V ±5% and 3.3V ±10%
–40°C to +85°C temperature range
Available in 16-pin (3mm ××
××
× 3mm) MLF® package
FEATURES
5GHz, 1:2 LVPECL FANOUT
BUFFER/TRANSLATOR
WITH INTERNAL INPUT TERMINATION
Precision Edge®
SY58012U
APPLICATIONS
All SONET and GigE clock distribution
Fibre Channel clock and data distribution
Backplane distribution
High-end, low skew, multiprocessor synchronous
clock distribution
Rev.: F Amendment: /0
Issue Date: May 2008
The SY58012U is a 2.5V/3.3V precision, high-speed, fully
differential 1:2 LVPECL fanout buffer. Optimized to provide
two identical output copies with less than 15ps of skew and
less than 10ps(pk-pk) total jitter, the SY58012U can process
clock signals as fast as 5GHz or 5Gbps data.
The differential input includes Micrel’s unique, 3-pin input
termination architecture that interfaces to LVPECL, LVDS
or CML differential signals, (AC-coupled or DC-coupled) as
small as 100mV without any level-shifting or termination
resistor networks in the signal path. For AC-coupled input
interface applications, an on-board output reference voltage
(VREF-AC) is provided to bias the VT pin. The outputs are
100k LVPECL compatible, with extremely fast rise/fall times
guaranteed to be less than 110ps.
The SY58012U operates from a 2.5V ±5% supply or
3.3V ±10% supply and is guaranteed over the full industrial
temperature range (–40°C to +85°C). For applications that
require faster rise/fall times, or greater bandwidth, consider
the SY58013U 1:2 fanout buffer with 400mV output swing,
or the SY58011 1:2 CML (400mV) fanout buffer. The
SY58012U is part of Micrel’s high-speed, Precision Edge®
product line. Data sheets and support documentation can
be found on Micrel’s web site at www.micrel.com.
FUNCTIONAL BLOCK DIAGRAM TYPICAL PERFORMANCE
IN
/IN
Q1
/Q1
Q0
/Q0
V
T
50
50
V
REF
-AC
2.5GHz Output
TIME (50ps/div.)
Output Swing
(200mV/div.)
V
CC
= 3.3V
2GHz with 100mV Input
Precision Edge®
Precision Edge is registered trademark of Micrel, Inc.
Micro
LeadFrame and MLF are registered trademarks of Amkor Technology, Inc.
2
Precision Edge®
SY58012U
Micrel, Inc.
M9999-051408
hbwhelp@micrel.com or (408) 955-1690
PACKAGE/ORDERING INFORMATION
Pin Number Pin Name Pin Function
1, 4 IN, /IN Differential Input: This input pair is the signal to be buffered. Each pin of this pair internally
terminates with 50 to the VT pin. Note that this input will default to an indeterminate state
if left open. See
Input Interface Applications
section.
2 VT Input Termination Center-Tap: Each input terminates to this pin. The VT pin provides a
center-tap for each input (IN, /IN) to a termination network for maximum interface flexibility.
See
Input Interface Applications
section.
3 VREF-AC Reference Output Voltage: This output biases to VCC 1.2V. It is used when AC-coupling
the inputs (IN, /IN). Connect VREF-AC directly to the VT pin. Bypass with 0.01µF low ESR
capacitor to VCC. Maximum current source or sink is 0.5mA. See
Input Interface
Applications
section.
5, 8, 13, 16 VCC Positive Power Supply: Bypass with 0.1µF//0.01µF low ESR capacitors as close to the
VCC pins as possible.
6, 7, 14, 15 GND, Ground. Exposed pad must be connected to a ground plane that is the same potential
Exposed Pad as the ground pin.
12, 11 Q0, /Q0, LVPECL Differential Output Pairs: Differential buffered output copy of the input signal. The
9, 10 Q1, /Q1 output swing is typically 800mV. Unused output pairs may be left floating with no impact on
jitter. See
LVPECL Output Termination
section.
PIN DESCRIPTION
13141516
12
11
10
9
1
2
3
4
8765
IN
VT
VREF-AC
/IN
Q0
/Q0
/Q1
Q1
VCC
GND
GND
VCC
VCC
GND
GND
VCC
16-Pin MLF® (MLF-16)
Ordering Information(1)
Package Operating Package Lead
Part Number Type Range Marking Finish
SY58012UMI MLF-16 Industrial 012U Sn-Pb
SY58012UMITR(2) MLF-16 Industrial 012U Sn-Pb
SY58012UMG(3) MLF-16 Industrial 012U with Pb-Free
Pb-Free bar-line indicator NiPdAu
SY58012UMGTR(2, 3) MLF-16 Industrial 012U with Pb-Free
Pb-Free bar-line indicator NiPdAu
Notes:
1. Contact factory for die availability. Dice are guaranteed at TA = 25°C, DC electricals only.
2. Tape and Reel.
3. Pb-Free package recommended for new designs.
3
Precision Edge®
SY58012U
Micrel, Inc.
M9999-051408
hbwhelp@micrel.com or (408) 955-1690
Absolute Maximum Ratings(Note 1)
Power Supply Voltage (VCC )...................... 0.5V to +4.0V
Input Voltage (VIN) ......................................... 0.5V to VCC
LVPECL Output Current (IOUT)
Continuous .............................................................50mA
Surge....................................................................100mA
Source or sink current on VT pin
VT Current ..........................................................±100mA
Source or sink current on IN, /IN
Input Current ........................................................±50mA
Source or sink current on VREF-AC, Note 4
VREF Current .......................................................±1.5mA
Soldering, (20 seconds) ............................................ 260°C
Storage Temperature Range (TSTORE )... 65°C to +150°C
Operating Ratings(Note 2)
Power Supply Voltage (VCC)..................... 2.375V to 3.60V
Operating Temperature Range (TA)...........40°C to +85°C
Package Thermal Resistance, Note 3
MLF® (θJA)
Still-Air .............................................................60°C/W
500 lpfm...........................................................54°C/W
MLF® (ψJB)..........................................................33°C/W
INPUT DC ELECTRICAL CHARACTERISTICS(Note 5)
VCC = 3.3V ±10% or 2.5 ±5%; RL= 50 to VCC2V; TA= 40°C to 85°C, unless otherwise stated.
Symbol Parameter Condition Min Typ Max Units
VOH Output HIGH Voltage Q0, /Q0, Q1, /Q1 VCC1.145 VCC0.895 V
VOL Output LOW Voltage Q0, /Q0, Q1, /Q1 VCC1.945 VCC1.695 V
VOUT Output Voltage Swing Q0, /Q0, Q1, /Q1; see Figure 1a 550 800 mV
VDIFF_OUT Differiential Output Voltage Swing Q0, /Q0, Q1, /Q1; see Figure 1b 1100 1600 mV
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 ratings condi-
tions 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. Thermal performance assumes exposed pad is soldered (or equivalent) to the devices most negative potential on the pcb.
Note 4. Due to the limited drive capability, use for input of the same package only.
Note 5. The circuit is designed to meet the dc specifications shown in the above table after thermal equilibrium has been established.
Note 6. VIH (min) not lower than 1.2V.
LVPECL OUTPUT DC ELECTRICAL CHARACTERISTICS(Note 5)
Symbol Parameter Condition Min Typ Max Units
VCC Power Supply Voltage 2.375 3.60 V
ICC Power Supply Current Max. VCC, no load 55 80 mA
VIH Input HIGH Voltage IN, /IN, Note 6 VCC1.6 VCC V
VIL Input LOW Voltage IN, /IN 0 VIH 0.1 V
VIN Input Voltage Swing IN, /IN; see Figure 1a 0.1 1.7 V
VDIFF_IN Differential Input Voltage Swing IN,/IN; see Figure 1b 0.2 V
RIN In to VT Resistance 40 50 60
IN to VT1.28 V
VREF-AC Output Reference Voltage VCC1.3 VCC 1.2 VCC1.1 V
4
Precision Edge®
SY58012U
Micrel, Inc.
M9999-051408
hbwhelp@micrel.com or (408) 955-1690
TIMING DIAGRAM
/IN
IN
/Q
Qt
pd
SINGLE-ENDED AND DIFFERENTIAL SWINGS
V
IN
,
V
OUT
Typ. 800mV
Figure 1a. Single-Ended Voltage Swing
VDIFF_IN,
VDIFF_OUT Typ. 1.6V
Figure 1b. Differential Voltage Swing
VCC = 2.5V ±5% or 3.3V ±10%; TA = 40°C to +85°C; RL = 50 to VCC2V, unless otherwise stated.
Symbol Parameter Condition Min Typ Max Units
fMAX Maximum Operating Frequency NRZ Data 5 Gbps
VOUT 400mV Clock 5 GHz
tpd Propagation Delay VIN 100mV 110 170 260 ps
tCHAN Channel-to-Channel Skew Note 8 315ps
tSKEW Part-to-Part Skew Note 9 100 ps
tJITTER Data Random Jitter (RJ) Note 10 1ps
RMS
Deterministic Jitter (DJ) Note 11 10 psPP
Clock Cycle-to-Cycle Jitter Note 12 1ps
RMS
Total Jitter (TJ) Note 13 10 psPP
tr, tfOutput Rise/Fall Time 20% to 80% at full output swing 35 80 110 ps
Note 7. High frequency AC Electricals are guaranteed by design and characterization.
Note 8. Skew is measured between outputs of the same bank under identical transitions.
Note 9. Skew is defined for two parts with identical power supply voltages at the same temperature and with no skew of the edges at the respective
inputs.
Note 10. RJ is measured with a K28.7 comma detect character pattern, measured at 10.7Gbps and 2.5Gbps/3.2Gbps.
Note 11. DJ is measured at 10.7Gbps and 2.5Gbps/3.2Gbps with both K28.5 and 2231 PRBS pattern
Note 12. Cycle-to-cycle jitter definition: The variation of periods between adjacent cycles, TnTn1 where T is the time between rising edges of the
output signal.
Note 13. Total jitter definition: With an ideal clock input of frequency fMAX, no more than one output edge in 1012 output edges will deviate by more
than the specified peak-to-peak jitter value.
AC ELECTRICAL CHARACTERISTICS(Note 7)
5
Precision Edge®
SY58012U
Micrel, Inc.
M9999-051408
hbwhelp@micrel.com or (408) 955-1690
TYPICAL OPERATING CHARACTERISTICS
VCC = 3.3V, GND = 0, VIN = 100mV, TA = 25°C, unless otherwise stated.
0
1
2
3
4
5
6
7
8
9
10
-40 -20 0 20 40 60 80 100
WITHIN-DEVICE SKEW (ps)
TEMPERATURE (°C)
Within-Device Skew vs.
Temperature
155
160
165
170
175
180
185
190
0 200 400 600 800 1000
PROPAGATION DELAY (ps)
INPUT VOLTAGE SWING (V)
Propagation Delay vs.
Input Volta
g
e Swin
g
135
140
145
150
155
160
165
170
175
180
185
190
195
-40 -20 0 20 40 60 80 100
PROPAGATION DELAY (ps)
TEMPERATURE (°C)
Propagaton Delay vs.
Temperature
0
100
200
300
400
500
600
700
800
0
1000
2000
3000
4000
5000
6000
7000
8000
9000
AMPLITUDE (mV)
FREQUENCY (MHz)
Frequency vs. Amplitude
6
Precision Edge®
SY58012U
Micrel, Inc.
M9999-051408
hbwhelp@micrel.com or (408) 955-1690
FUNCTIONAL CHARACTERISTICS
VCC = 3.3V, GND = 0, VIN = 100mV, TA = 25°C, unless otherwise stated.
5Gbps Output
TIME (50ps/div.)
Output Swing
(150mV/div.)
5GHz Output
TIME (25ps/div.)
Output Swing
(100mV/div.)
200MHz Output
TIME (600ps/div.)
Output Swing
(200mV/div.)
(2231 PRBS Pattern)
7
Precision Edge®
SY58012U
Micrel, Inc.
M9999-051408
hbwhelp@micrel.com or (408) 955-1690
INPUT STAGE
50
50
VCC
GND
/IN
VT
IN
Figure 2. Simplified Differential
Input Buffer
INPUT INTERFACE APPLICATIONS
CML IN
/IN
VTNC
SY58012U
V
CC
V
CC
V
REF
-ACNC
Figure 3d. DC-Coupled CML
Input Interface
(option: may connect VT to VCC)
0.01µF
V
CC
LVPECL
IN
/IN
SY58012U
V
CC
V
REF
-AC
VT
V
CC
NC
R
pd
Note:
For V
CC
= 2.5V systems, R
pd
= 19Ω.
For V
CC
= 3.3V systems, R
pd
= 50Ω.
Figure 3a. LVPECL
Input Interface
LVPECL
IN
/IN
VT
SY58012U
VCC VCC
VCC
0.01µF
Rpd
Rpd
VREF-AC
Note:
For VCC = 3.3V system, Rpd = 100
For VCC = 2.5V system, Rpd = 50
Figure 3b. AC-Coupled LVPECL
Input Interface
LVDS IN
/IN
VTNC
SY58012U
V
CC
V
CC
V
REF
-ACNC
Figure 3c. LVDS
Input Interface
0.1µF
V
CC
CML
IN
/IN
SY58012U
V
CC
V
REF-AC
VT
V
CC
Figure 3e. AC-Coupled CML
Input Interface
8
Precision Edge®
SY58012U
Micrel, Inc.
M9999-051408
hbwhelp@micrel.com or (408) 955-1690
Part Number Function Data Sheet Link
SY58011U 7GHz, 1:2 CML Fanout Buffer/Translator http://www.micrel.com/product-info/products/sy58011u.shtml
With Internal Input Termnations
SY58012U 5GHz, 1:2 LVPECL Fanout Buffer/Translator http://www.micrel.com/product-info/products/sy58012u.shtml
With Internal Input Termination
SY58013U 6GHz, 1:2 Fanout Buffer/Translator w/400mV http://www.micrel.com/product-info/products/sy58013u.shtml
LVPECL Outputs and Internal Terminations
16-MLF Manufacturing Guidelines www.amkor.com/products/notes_papers/MLF_AppNote_0902.pdf
Exposed Pad Application Note
M-0317 HBW Solutions http://www.micrel.com/product-info/as/solutions.shtml
RELATED MICREL PRODUCTS AND SUPPORT DOCUMENTATION
R2
82
R2
82
ZO = 50
ZO = 50
+3.3V* +3.3V*
VT = VCC 2
V
R1
130R1
130
+3.3V*
Figure 5. Parallel Termination-Thevenin Equivalent
Note 1. For +2.5V systems: R1 = 250, R2 = 62.5
Note 2. For +3.3V systems: R1 = 130, R2 = 82
Z = 50
Z = 50
5050
50
+3.3V +3.3V
source destination
RbC1
0.01µF
(optional)
Figure 6. Three-Resistor YTermination
Note 1. Power-saving alternative to Thevenin termination.
Note 2. Place termination resistors as close to destination inputs as possible.
Note 3. Rb resistor sets the DC bias voltage, equal to VT.
For +2.5V systems Rb = 19.
For +3.3V systems Rb = 46 to 50.
Note 4. C1 is an optional bypass capacitor intended to compensate for any
tr/tf mismatches.
LVPECL OUTPUT
+3.3V +3.3V
ZO = 50
R2
82
+3.3V +3.3V
R1
130R1
130
R2
82
VT = VCC 2V
Q
/Q
R4
1k
R3
1.6k
VT = VCC 1.3V
Figure 7. Terminating Unused I/O
Note 1. Unused output (/Q) must be terminated to balance the output.
Note 2. For +2.5V systems: R1 = 250, R2 = 62.5, R3 = 1.25k,
R4 = 1.2k.
For +3.3V systems: R1 = 130, R2 = 82, R3 = 1k, R4 = 1.6k.
Note 3. Unused output pairs (Q and /Q) may be left floating.
LVPECL output have very low output impedance (open
emitter), and small signal swing which results in low EMI.
LVPECL is ideal for driving 50 and 100 controlled
impedance transmission lines. There are several techniques
in terminating the LVPECL output, as shown in Figures 5
through 7.
9
Precision Edge®
SY58012U
Micrel, Inc.
M9999-051408
hbwhelp@micrel.com or (408) 955-1690
16-PIN
Micro
LeadFrame® (MLF-16)
Package
EP- Exposed Pad
Die
CompSide Island
Heat Dissipation
Heavy Copper Plane
Heavy Copper Plane
VEE
VEE
Heat Dissipation
PCB Thermal Consideration for 16-Pin MLF® Package
(Always solder, or equivalent, the exposed pad to the PCB)
Package Notes:
Note 1. Package meets Level 2 qualification.
Note 2. All parts are dry-packaged before shipment.
Note 3. Exposed pads must be soldered to a ground for proper thermal management.
MICREL, INC. 2180 FORTUNE DRIVE SAN JOSE, CA 95131 USA
TEL + 1 (408) 944-0800 FAX + 1 (408) 474-1000 WEB http://www.micrel.com
The information furnished by Micrel in this datasheet is believed to be accurate and reliable. However, no responsibility is assumed by Micrel for its use.
Micrel reserves the right to change circuitry and specifications at any time without notification to the customer.
Micrel Products are not designed or authorized for use as components in life support appliances, devices or systems where malfunction of a product can
reasonably be expected to result in personal injury. Life support devices or systems are devices or systems that (a) are intended for surgical implant into
the body or (b) support or sustain life, and whose failure to perform can be reasonably expected to result in a significant injury to the user. A Purchasers
use or sale of Micrel Products for use in life support appliances, devices or systems is at Purchasers own risk and Purchaser agrees to fully indemnify
Micrel for any damages resulting from such use or sale.
© 2005 Micrel, Incorporated.