ETC SY89831U

2GHz ANY DIFF. IN-TO-LVPECL ULTRA
Precision Edge™
LOW-JITTER AND SKEW 1:4 FANOUT
SY89831U
FINAL
BUFFER/TRANSLATOR W/ INTERNAL TERMINATION
FEATURES
■ Guaranteed AC performance over temperature
and voltage
• > 2.0GHz fMAX
• < 20ps within-device skew
• < 225ps rise/fall times
■ Low jitter design
• < 1ps(rms) cycle-to-cycle
• < 10ps(pk-pk) total jitter
■ Unique input termination and VT pin for DC-coupled
and AC-coupled inputs (CML, HSTL, and LVPECL)
■ Fully differential I/O design
■ Low power 2.5V and 3.3V power supply
■ TTL/CMOS compatible enable input
■ Wide operating temperature range: –40°C to +85°C
■ Available in 16-pin (3mm × 3mm) MLF™ package
Precision Edge™
DESCRIPTION
The SY89831U is a high-speed, 2GHz differential
LVPECL 1:4 fanout buffer optimized for ultra-low skew
applications. Within device skew is guaranteed to be less
than 20ps (5ps typ.) over supply voltage and temperature.
The differential input buffer has a unique internal termination
design that allows access to the termination network through
a VT pin. This feature allows the device to easily interface
to different logic standards. A VREF–AC reference output is
included for AC-coupled applications.
The SY89831U is a part of Micrel's high-speed clock
synchronization family. For applications that require a
different I/O combination, consult Micrel’s website at
www.micrel.com, and choose from a comprehensive product
line of high-speed, low-skew fanout buffers, translators and
clock generators.
APPLICATIONS
■
■
■
■
Processor clock distribution
SONET clock distribution
Fibre Channel clock distribution
Gigabit Ethernet clock distribution
FUNCTIONAL BLOCK DIAGRAM
TYPICAL PERFORMANCE
155MHz Output
Q0
/Q0
Output Swing
(150mV/div.)
/Q
Q1
IN
VT
/IN
/Q1
50Ω
50Ω
Q2
TA = 25°C
VCC = 3.3V
VEE GND
VIN = 800mV
Q
/Q2
EN
VREF—AC
D
Q
Q3
TIME (1ns/div.)
/Q3
Precision Edge is a trademark of Micrel, Inc.
MicroLeadFrame and MLF are trademarks of Amkor Technology, Inc.
Rev.: C
1
Amendment: /0
Issue Date: February 2003
Precision Edge™
SY89831U
Micrel
PACKAGE/ORDERING INFORMATION
/Q0
Q0
VCC
GND
Ordering Information
16 15 14 13
Q1
1
12
IN
/Q1
2
11
Q2
/Q2
3
4
10
9
VT
VREF–AC
/IN
Part Number
Package
Type
Operating
Range
Package
Marking
SY89831UMI
MLF-16
Industrial
831U
SY89831UMITR*
MLF-16
Industrial
831U
*Tape and Reel
Q3
/Q3
VCC
EN
5 6 7 8
16-Pin MLF™
PIN DESCRIPTION
Pin Number
Pin Name
15, 16
1, 2, 3, 4, 5, 6
(Q0, /Q0) to
(Q3, /Q3)
Pin Function
LVPECL Differential (Outputs): Terminate to VCC–2V. See “Termination Recommendations”
section. Unused output pairs may be left floating with no impact on jitter.
8
EN
TTL/CMOS Compatible Synchronous Enable: When EN goes LOW, Q outputs will go LOW
and /Q outputs will go HIGH on the next LOW transition at D inputs. Input threshold is VCC/2V.
Includes a 25kΩ pull-up resistor. Default state is HIGH when left floating. The internal latch is
clocked on the falling edge of the input signal (IN, /IN).
9, 12
/IN, IN
10
VREF–AC
Reference Voltage: Equal to VCC–1.4V (approx.), and used for AC–coupled applications.
Maximum sink/source current is 0.5mA. See “Input Interface Applications” section. When using
VREF–AC, bypass with a 0.01µF capacitor to VCC.
11
VT
Termination Center-Tap: For CML inputs, leave this pin floating. Otherwise, see Figures 2a to 2e
in “Input Interface Applications” section.
13,
Exposed Pad
GND
Ground. Exposed pad is internally connected to GND and must be connected to a ground plane
for proper thermal operation.
14
VCC
Positive Power Supply: Bypass with 0.1µF//0.01µF low ESR capacitors.
Differential Clock (Inputs): Internal 50Ω termination resistors to VT pin. See “Input Interface
Applications” section.
TRUTH TABLE
IN
/IN
EN
Q
/Q
0
1
1
0
1
1
0
1
1
0
0
0(1)
1(1)
X
Note 1.
X
On next negative transition of the input signal (IN).
2
Precision Edge™
SY89831U
Micrel
Absolute Maximum Ratings(Note 1)
Operating Ratings(Note 2)
Supply Voltage (VCC) .................................. –0.5V to +4.0V
Input Voltage (VIN) ............................... –0.5V to VCC +0.5V
Output Current (IOUT)
Continuous ......................................................... 50mA
Surge ................................................................ 100mA
Input Current (IN, /IN) ............................................... ±50mA
VT Current (IVT) ....................................................... ±100µA
Input Sink/Source Current (VREF–AC), Note 3 ......... ±0.5mA
Lead Temperature (soldering, 10sec.) ...................... 220°C
Storage Temperature (TS) ....................... –65°C to +150°C
Supply Voltage Range .......................... +2.375V to +3.63V
Ambient Temperature (TA) ......................... –40°C to +85°C
Package Thermal Resistance
MLF™ (θJA)
Still-Air ............................................................. 60°C/W
500lfpm ............................................................ 54°C/W
MLF™ (ΨJB), Note 4
Junction-to-Board ............................................ 32°C/W
Note 1.
Note 2.
Note 3.
Note 4.
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.
The data sheet limits are not guaranteed if the device is operated beyond the operating ratings.
Due to the limited drive capability use for input of the same package only.
Junction-to-board resistance assumes exposed pad is soldered (or equivalent) to the device’s most negative potential on the PCB.
DC ELECTRICAL CHARACTERISTICS(Note 1, 2)
TA = –40°C to +85°C
Symbol
Parameter
VCC
Power Supply Voltage Range
ICC
Power Supply Current
RIN
Differential Input Resistance (IN, /IN)
VIH
Input HIGH Voltage (IN, /IN)
Note 3
VIL
Input LOW Voltage (IN, /IN)
Note 3
VIN
Input Voltage Swing
VDIFF_IN
|IIN|
Note 1.
Note 2.
Note 3.
Condition
Min
Typ
Max
Units
3.63
V
47
70
mA
100
120
Ω
1.2
VCC
V
0
VCC–0.1
V
Note 3, see Figure 1a, and 1b.
VT floating for VIN (max.)
0.1
2.8
V
Differential Input Voltage Swing,
see Figure 1a, and 1b.
Note 3
0.2
Input Current (IN, /IN)
Note 3
2.375
No load, maximum supply voltage
80
V
35
mA
The circuit is designed to meet the DC specifications shown in the above table after thermal equilibrium has been established.
Specification for packaged product ony.
Due to the internal termination (see “Differential Input” ) the input current depends on the applied voltages at IN, /IN and VT inputs. Do not apply
a combination of voltages that causes the input current to exceed the maximum limit.
LVTTL/LVCMOS INPUT DC ELECTRICAL CHARACTERISTICS(Note 1)
VCC = 2.375V to 3.63V; VEE = 0V; TA = –40°C to +85°C
Symbol
Parameter
VIH
Input HIGH Voltage
VIL
Max
Units
2.0
VCC
V
Input LOW Voltage
0
0.8
V
IIH
Input HIGH Current
20
–125
µA
IIL
Input LOW Current
–300
µA
Note 1.
Condition
Min
Specification for packaged product ony.
3
Typ
Precision Edge™
SY89831U
Micrel
2.5V (100KEP) LVPECL DC ELECTRICAL CHARACTERISTICS(Note 1, 2)
VCC = 2.5V ±5%; VEE = 0V; TA = –40°C to +85°C
Symbol
Parameter
Condition
Min
Typ
Max
Units
VOH
Output HIGH Voltage
RL = 50Ω to VCC–2V
1355
1480
1605
mV
VOL
Output LOW Voltage
RL = 50Ω to VCC–2V
555
680
805
mV
VOUT
Output Voltage Swing
see Figure 1a, and 1b
550
800
1050
mV
VDIFF_OUT
Differential Output Voltage Swing
see Figure 1a, and 1b
1100
1600
2100
mV
Note 1.
Note 2.
The circuit is designed to meet the DC specifications shown in the above table after thermal equilibrium has been established. The circuit is in a
test socket or mounted on a printed circuit board and traverse airflow greater than 500lfpm is maintained. Parameters are for VCC = 2.5V. They
vary 1:1 with VCC.
Specification for packaged product only.
3.3V (100KEP) LVPECL DC ELECTRICAL CHARACTERISTICS(Note 1, 2)
VCC = 3.3V ±10%; VEE = 0V; TA = –40°C to +85°C
Symbol
Parameter
Condition
Min
Typ
Max
Units
VOH
Output HIGH Voltage
RL = 50Ω to VCC–2V
2155
2280
2405
mV
VOL
Output LOW Voltage
RL = 50Ω to VCC–2V
1355
1480
1605
mV
VREF–AC
Reference Voltage, Note 2
1755
1875
1975
mV
Note 1.
Note 2.
Note 3.
The circuit is designed to meet the DC specifications shown in the above table after thermal equilibrium has been established.
Specification for packaged product only.
Single-ended input operation is limited to VCC ≥ 3.0V.
4
Precision Edge™
SY89831U
Micrel
AC ELECTRICAL CHARACTERISTICS(Note 1, 2)
VCC = 2.375 to 3.63V; VEE = 0V; TA = –40°C to +85°C, output loading is 50Ω to VCC–2V, unless otherwise noted.
Symbol
Parameter
Condition
Min
Typ
fMAX
Maximum Frequency
Output Swing ≥ 450mV
2.0
2.5
tPLH
tPHL
Propagation Delay-to-Output
(Differential)
Input Swing: 100mV
tSKEW
Within-Device Skew (Differential)
Note 3
Input Swing: 800mV
250
Max
Units
GHz
390
0
ps
350
450
ps
5
20
ps
150
ps
Part-to-Part Skew (Differential)
tS
Set-Up Time (EN to IN, /IN)
Note 4
300
ps
tH
Hold Time (EN to IN, /IN)
Note 4
300
ps
tJITTER
Cycle-to-Cycle Jitter (rms)
Note 5
1
ps(rms)
Total Jitter
Note 6
10
ps(pk-pk)
225
ps
t r, t f
Output Rise/Fall Times
(20% to 80%)
70
150
Note 1.
Measured with 400mV input signal, 50% duty cycle, all loading with 50Ω to VCC–2V. Output swing is ≥ 450mV.
Note 2.
Specification for packaged product only.
Note 3.
Skew is measured between outputs under identical transitions.
Note 4.
Set-up and hold times apply to synchronous applications that intend to enable/disable before the next clock cycle. For asynchronous applications, set-up and hold times do not apply.
Note 5.
Cycle-to-cycle jitter definition: The variation period between adjacent cycles over a random sample of adjacent cycle pairs.
TJITTER_CC = Tn –Tn+1, where T is the time between rising edges of the output signal.
Note 6.
Total jitter definition: with an ideal clock input frequency of ≤ fMAX (device), no more than one output edge in 1012 output edges will deviate by
more than the specified peak-to-peak jitter value.
TIMING DIAGRAM
EN
VCC/2
tS
VCC/2
tH
/IN
IN
VIN
tPLH, tPLH
/Q
VOUT Swing
Q
DEFINITION OF SINGLE-ENDED AND DIFFERENTIAL SWING
QOUT
QOUT
VIN, VOUT
800mV (typical)
VDIFF_IN, VDIFF_OUT
1.6V (typical)
/QOUT
/QOUT
Figure 1a. Single-Ended Swing
Figure 1b. Differential Swing
5
Precision Edge™
SY89831U
Micrel
TYPICAL OPERATING CHARACTERISTICS
VCC = 3.3V, VEE = GND, TA = 25°C, unless otherwise stated.
Output Swing
vs. Frequency
390
PROPAGATION DELAY (ps)
900
AMPLITUDE (mV)
800
700
600
500
400
300
200
100
0
0
380
370
360
350
340
330
320
310
300
-40 -20 0 20 40 60 80 100
TEMPERATURE (°C)
3000
Propagation Delay
vs. Input Voltage Swing
25
425
400
375
350
15
10
5
325
300
100
t
SKEW
vs. Temperature
20
tSKEW (ps)
PROPAGATION DELAY (ps)
450
1000
2000
FREQUENCY (MHz)
Propagation Delay
vs. Temperature
0
-40 -20 0 20 40 60 80 100
TEMPERATURE (°C)
300
500
700
900
INPUT VOLTAGE SWING (V)
6
Precision Edge™
SY89831U
Micrel
FUNCTIONAL CHARACTERISTICS
VCC = 3.3V, VEE = 0V, VIN = 800mV, TA = 25°C, unless otherwise stated.
622MHz Output
155MHz Output
/Q
Output Swing
(150mV/div.)
Output Swing
(150mV/div.)
/Q
Q
Q
TIME (200ps/div.)
TIME (1ns/div.)
1GHz Output
Output Swing
(150mV/div.)
/Q
Q
TIME (150ps/div.)
7
Precision Edge™
SY89831U
Micrel
FUNCTIONAL BLOCK DIAGRAM
Q0
/Q0
Q1
IN
VT
/IN
/Q1
50Ω
50Ω
Q2
/Q2
EN
D
Q
Q3
VREF—AC
/Q3
DIFFERENTIAL INPUT
VCC
IN
50Ω
VT
50Ω
/IN
SY89831U
Figure 2. Input Stage
8
Precision Edge™
SY89831U
Micrel
INPUT INTERFACE APPLICATIONS
VCC
VCC
VCC
VCC
VCC
VCC
D
PECL
D
D
/D
PECL
SY89831U
/D
Rpd
CML
/D
VCC
Rpd
VT
SY89831U
SY89831U
VCC —2V
0.01µF
VT
VREF—AC
50Ω
VBB
Figure 3a. DC-Coupled PECL
Input Interface
VCC
VCC
VT
For 2.5V, Rpd = 50Ω
For 3.3V, Rpd = 100Ω
Figure 3b. AC-Coupled PECL
Input Interface
VCC
VCC
D
IN
CML
HSTL
/D
/IN
SY89831U
SY89831U
VCC
NC
0.01µF
VT
VREF—AC
VT
NC
VREFÐAC
0.01µF
Figure 3d. AC-Coupled CML
Input Interface
Figure 3e. HSTL
Input Interface
9
Figure 3c. DC-Coupled CML
Input Interface
Precision Edge™
SY89831U
Micrel
OUTPUT TERMINATION RECOMMENDATIONS
+3.3V
+3.3V
ZO = 50Ω
R1
130Ω
R1
130Ω
+3.3V
+3.3V
+3.3V
Z = 50Ω
Z = 50Ω
ZO = 50Ω
50Ω
R2
82Ω
50Ω
source
R2
82Ω
Vt = VCC —2V
destination
50Ω
Rb
C1
0.01µF
(optional)
Figure 5. Three-Resistor “Y-Termination”
Figure 4. Parallel Termination—Thevenin Equivalent
Note 1.
For +2.5V systems: R1 = 250Ω, R2 = 62.5Ω
Note 1.
Power-saving alternative to Thevenin termination.
Note 2.
For +3.3V systems: R1 = 130Ω, R2 = 82Ω
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 = 39Ω.
For +3.3V systems Rb = 46Ω to 50Ω.
Note 4.
+3.3V
+3.3V
Q
C1 is an optional bypass capacitor intended to compensate for
any tr/tf mismatches.
+3.3V
R1
130Ω
R1
130Ω
V = VCC —1.3V
R4 t
+3.3V
1kΩ
ZO = 50Ω
/Q
R3
1.6kΩ
Vt = VCC —2V
R2
82Ω
R2
82Ω
Figure 6. Terminating Unused I/O
Note 1.
Note 2.
Note 3.
Unused output (/Q) must be terminated to balance the output.
For +2.5V systems: R1 = 250Ω, R2 = 62.5Ω, R3 = 1.25kΩ, R4 = 1.2kΩ.
For +3.3V systems: R1 = 130Ω, R2 = 82Ω, R3 = 1.6kΩ, R4 = 1k.
Unused output pairs (Q and /Q) may be left floating.
RELATED PRODUCT AND SUPPORT DOCUMENTATION
Part Number
Function
Data Sheet Link
SY89830U
1:4 LVPECL Fanout Buffer w/2:1 Mux Input
www.micrel.com/product-info/products/sy89830u.shtml
SY89832U
2GHz Ultra Low-Jitter and Skew 1:4 LVPECL
Fanout Buffer/Translator w/Internal Termination
www.micrel.com/product-info/products/sy89832u.shtml
SY89833U
2GHz Any Diff. In-to-LVDS Out 1:4
Fanout Buffer/Translator w/Internal Termination
www.micrel.com/product-info/products/sy89833u.shtml
HBW Solutions
New Products and Applications
www.micrel.com/product-info/products/solutions.shtml
16-MLF™ Manufacturing Guidelines
Exposed Pad Application Note
www.amkor.com/products/notes_papers/MLF_AppNote_0301.pdf
10
Precision Edge™
SY89831U
Micrel
16 LEAD EPAD MicroLeadFrame™ (MLF-16)
0.42 +0.18
–0.18
0.23 +0.07
–0.05
0.85 +0.15
–0.65
0.01 +0.04
–0.01
3.00BSC
1.60 +0.10
–0.10
0.65 +0.15
–0.65
0.20 REF.
2.75BSC
0.42
PIN 1 ID
+0.18
–0.18
N
16
1
1
0.50 DIA
2
2
2.75BSC 3.00BSC
3
3
1.60 +0.10
–0.10
4
4
12° max
0.5 BSC
0.42 +0.18
–0.18
SEATING
PLANE
0.40 +0.05
–0.05
1.5 REF
BOTTOM VIEW
TOP VIEW
CC
0.23 +0.07
–0.05
CL
4
0.01 +0.04
–0.01
SECTION "C-C"
SCALE: NONE
0.5BSC
1.
2.
3.
4.
DIMENSIONS ARE IN mm.
DIE THICKNESS ALLOWABLE IS 0.305mm MAX.
PACKAGE WARPAGE MAX 0.05mm.
THIS DIMENSION APPLIES TO PLATED TERMINAL AND IS MEASURED
BETWEEN 0.20mm AND 0.25mm FROM TIP.
5. APPLIES ONLY FOR TERMINALS
FOR EVEN TERMINAL/SIDE
Rev. 02
Package
EP- Exposed Pad
Die
CompSide Island
Heat Dissipation
Heat Dissipation
VEE
Heavy Copper Plane
VEE
Heavy Copper Plane
PCB Thermal Consideration for 16-Pin MLF™ Package
(Always solder, or equivalent, the exposed pad to the PCB)
Package Notes:
Note 1.
Note 2.
Package meets Level 2 moisture sensitivity classification, and are shipped in dry-pack form.
Exposed pads must be soldered to a ground for proper thermal management.
MICREL, INC.
TEL
1849 FORTUNE DRIVE SAN JOSE, CA 95131 USA
+ 1 (408) 944-0800
FAX
+ 1 (408) 944-0970
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 Purchaser’s
use or sale of Micrel Products for use in life support appliances, devices or systems is at Purchaser’s own risk and Purchaser agrees to fully indemnify
Micrel for any damages resulting from such use or sale.
© 2003 Micrel, Incorporated.
11