MICREL SY89871UMG

Precision Edge®
2.5GHz ANY DIFF. IN-TO-LVPECL
®
SY89871U
Precision Edge
PROGRAMMABLE CLOCK DIVIDER/
SY89871U
FANOUT BUFFER W/INTERNAL TERMINATION
Micrel, Inc.
FEATURES
Precision Edge®
„ Two matched-delay outputs:
• Bank A: undivided pass-through (QA)
• Bank B: programmable divide by
2, 4, 8, 16 (QB0, QB1)
„ Matched delay: all outputs have matched delay,
independent of divider setting
„ Guaranteed AC performance:
• >2.5GHz fMAX
• <250ps tr/tf
• <670ps tpd (matched delay)
• <15ps within-device skew
„ Low jitter design
• <1psRMS cycle-to-cycle jitter
• <10psPP total jitter
„ Power supply 3.3V or 2.5V
„ Unique patent-pending input termination and VT pin
for DC- and AC-coupled inputs: any differential
inputs (LVPECL, LVDS, CML, HSTL)
„ TTL/CMOS inputs for select and reset
„ 100K EP compatible LVPECL outputs
„ Parallel programming capability
„ Wide operating temperature range: –40°C to +85°C
„ Available in 16-pin (3mm x 3mm) MLF® package
DESCRIPTION
The SY89871U is a 2.5V/3.3V LVPECL output precision
clock divider capable of accepting a high-speed differential
clock input (AC or DC-coupled) CML, LVPECL, HSTL or
LVDS clock input signal and dividing down the frequency
using a programmable divider ratio to create a frequencylocked lower speed version of the input clock (Bank B).
Available divider ratios are 2, 4, 8 and 16. In a typical
622MHz clock system this would provide availability of
311MHz, 155MHz, 77MHz, or 38MHz auxiliary clock
components.
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 is included for AC-coupled applications.
The SY89871U includes two phase-matched output
banks. Bank A (QA) is a frequency-matched copy of the
input. Bank B (QB0, QB1) is a divided down output of the
input frequency. Bank A and Bank B maintain a matched
delay independent of the divider setting.
All support documentation can be found on Micrel’s web
site at: www.micrel.com.
APPLICATIONS
„
„
„
„
OC-3 to OC-192 SONET/SDH applications
Transponders
Oscillators
SONET/SDH line cards
FUNCTIONAL BLOCK DIAGRAM
TYPICAL PERFORMANCE
QA
QA@622MHz and [email protected]
/QA
VREF-AC
QA
QB0
IN
Divided
by
2, 4, 8
or 16
50Ω
VT
50Ω
622MHz
Output
/QB0
/QA
QB1
/IN
QB0
/QB1
S0
155.5MHz
Output
Decoder
÷4
S1
/QB0
/RESET
Precision Edge is a registered trademark of Micrel, Inc.
MicroLeadFrame and MLF are registered trademarks of Amkor Technology, Inc.
M9999-082407
[email protected] or (408) 955-1690
Rev.: F
1
Amendment: /0
Issue Date: August 2007
Precision Edge®
SY89871U
Micrel, Inc.
S0
S1
VCC
GND
PACKAGE/ORDERING INFORMATION
16
15
14
13
Ordering Information
11
VT
QB1
3
10
VREF-AC
/QB1
4
9
6
7
8
VCC
IN
/RESET
12
2
/QA
1
QA
QB0
/QB0
5
Package Operating
Type
Range
Part Number
Package
Marking
Lead
Finish
SY89871UMI
MLF-16
Industrial
871U
Sn-Pb
SY89871UMITR(1)
MLF-16
Industrial
871U
Sn-Pb
SY89871UMG(2)
MLF-16
Industrial
871U with
Pb-Free bar line indicator
NiPdAu
Pb-Free
SY89871UMGTR(1, 2)
MLF-16
Industrial
871U with
Pb-Free bar line indicator
NiPdAu
Pb-Free
/IN
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 is recommended for new designs.
16-Pin MLF® (MLF-16)
PIN DESCRIPTION
Pin Number
Pin Name
Pin Function
1, 2, 3, 4
QB0, /QB0
QB1, /QB1
Differential Buffered Output Clocks: This differential output is a divided-down version of
the input frequency and has a matched output delay with Bank A. Divided by 2, 4, 8, or 16.
See “Truth Table.” Unused output pairs may be left floating.
5, 6
QA, /QA
7, 14
VCC
8
/RESET
12, 9
IN, /IN
10
VREF-AC
11
VT
13
GND
15, 16
S1, S0
Differential Buffered Undivided Output Clock.
Positive Power Supply: Bypass with 0.1µF™™0.01µF low ESR capacitors.
Output Reset: Internal 25ký pull-up. Logic LOW will reset the divider select. See “Truth
Table.” Input threshold is VCC/2.
Differential Input: Internal 50ý termination resistors to VT input. See “Input Interface
Applications” section.
Reference Voltage: Equal to VCC–1.4V (approx.), and used for AC-coupled applications.
For DC-coupled applications, VREF-AC is normally left floating. Maximum sink/source
current is 0.5mA. See “Input Interface Applications” section.
Input Termination Center-Tap: Each side of differential input pair terminates to this pin.
The VT pin provides a center tap to a termination network for maximum interface flexibilty.
For CML and LVDS inputs, leave this pin floating. See “Input Interface Application” section.
Ground.
Select Pins: See “Truth Table.” LVTTL/CMOS logic levels. Internal 25ký pull-up resistor.
Logic HIGH if left unconnected (divided by 16 mode). S0 = LSB. Input threshold is VCC/2.
TRUTH TABLE
/RESET
S1
S0
Bank A Output
Bank B Outputs
1
0
0
Input Clock
Input Clock ÷2
1
0
1
Input Clock
Input Clock ÷4
1
1
0
Input Clock
Input Clock ÷8
1
1
1
Input Clock
Input Clock ÷16
0
X
X
Input Clock
QB = LOW, /QB = HIGH
M9999-082407
[email protected] or (408) 955-1690
2
Precision Edge®
SY89871U
Micrel, Inc.
Absolute Maximum Ratings(1)
Operating Ratings(2)
Supply Voltage (VCC) ................................... –0.5V to +4.0V
Input Voltage (VIN) ............................... –0.5V to VCC +0.3V
PECL Output Current (IOUT)
Continuous .......................................................... 50mA
Surge .................................................................100mA
VT Current (IVT) ...................................................... ±100mA
Input Current IN, /IN (IIN) .......................................... ±50mA
VREF-AC Sink/Source Current (IVREF-AC) .................... ±2mA
Lead Temperature (soldering, 20 sec.) ..................... 260°C
Storage Temperature (TS) ........................ –65°C to +150°C
Supply Voltage (VCC) ............................. +2.375V to +3.63V
Ambient Temperature (TA) ......................... –40°C to +85°C
Package Thermal Resistance(3)
MLF® (θJA)
Still-Air ............................................................. 60°C/W
500lfpm ........................................................... 54°C/W
MLF® (ψJB)
Junction-to-board ............................................ 38°C/W
DC ELECTRICAL CHARACTERISTICS(4)
TA = –40°C to +85°C, unless otherwise stated.
Symbol
Parameter
Condition
Min
VCC
Power Supply Voltage
ICC
Power Supply Current
RIN
Differential Input Resistance,
(IN-to-/IN)
90
VIH
Input HIGH Voltage, (IN, /IN)
VIL
Input LOW Voltage, (IN, /IN)
VIN
Input Voltage Swing
VDIFF_IN
Typ
Max
Units
3.60
V
50
75
mA
100
110
ý
0.1
VCC+0.3
V
–0.3
VIH–0.1
V
Notes 5
0.1
VCC
V
Differential Input Voltage Swing
Notes 5, 6
0.2
|IIN|
Input Current, (IN, /IN)
Note 7
VREF-AC
Reference Voltage
2.37
No load, max VCC.
V
45
VCC–1.525 VCC–1.425 VCC–1.325
mA
V
Notes:
1. Permanent device damage may occur if ratings in the “Absolute Maximum Ratings” section are exceeded. This is a stress rating only and functional
operation is not implied for 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. Junction-to-board resistance assumes exposed pad is soldered (or equivalent) to the device's most negative potential on the PCB.
4. The circuit is designed to meet the DC specifications shown in the above table after thermal equilibrium has been established.
5. See “Timing Diagram” for VIN definition. VIN (max.) is specified when VT is floating.
6. See “Typical Operating Characteristics” section for VDIFF definition.
7. Due to the internal termination (see "Input Buffer Structure" section) 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!
M9999-082407
[email protected] or (408) 955-1690
3
Precision Edge®
SY89871U
Micrel, Inc.
(100KEP) LVPECL DC ELECTRICAL CHARACTERISTICS(8)
VCC = 3.3V ±10% or 2.5V ±5%; TA = –40°C to +85°C, RL = 50ý to VCC –2V, unless otherwise stated.
Symbol
Parameter
Condition
Min
Typ
Max
Units
VOH
Output HIGH Voltage
VCC–1.145 VCC–1.020 VCC–0.895
V
VOL
Output LOW Voltage
VCC–1.945 VCC–1.820 VCC–1.695
V
VOUT
Output Voltage Swing
550
800
1050
mV
VDIFF_OUT
Differential Output Voltage Swing
1.10
1.6
2.1
V
LVTTL/LVCMOS DC ELECTRICAL CHARACTERISTICS(8)
VCC = 3.3V ±10% or 2.5V ±5%; TA = –40°C to +85°C.
Symbol
Parameter
VIH
Input HIGH Voltage
VIL
Input LOW Voltage
IIH
Input HIGH Current
IIL
Input LOW Current
Condition
Min
Typ
Max
2.0
–125
Units
V
0.8
V
20
µA
–300
µA
Note:
8. The circuit is designed to meet the DC specifications shown in the above table after thermal equilibrium has been established. Parameters are for
VCC = 2.5V. They vary 1:1 with VCC.
M9999-082407
[email protected] or (408) 955-1690
4
Precision Edge®
SY89871U
Micrel, Inc.
AC ELECTRICAL CHARACTERISTICS(9)
VCC = 3.3V ±10% or 2.5V ±5%; TA = –40°C to +85°C, unless otherwise stated.
Symbol
Parameter
Condition
Min
fMAX
Maximum Output Toggle Frequency
Output Swing ž 400mV
2.5
GHz
Maximum Input Frequency
Note 10
3.2
GHz
Differential Propagation Delay
Input Swing < 400mV
460
580
710
ps
IN-to-QA or QB
Input Swing ž 400mV
420
550
670
ps
Within-Device Skew (Differential)
QB0-to-QB1
Note 11
7
15
ps
Within-Device Skew (Differential)
QA-to-QB
Note 11
12
30
ps
Part-to-Part Skew (Differential)
Note 11
250
ps
Cycle-to-Cycle Jitter
Note 12
1
psRMS
Total Jitter
Note 13
10
psPP
tPD
tSKEW
tJITTER
tRR
Reset Recovery Time
600
tr, tf
Output Rise/Fall Times
(20% to 80%)
70
Typ
Max
Units
ps
150
250
ps
Notes:
9. Measured with 400mV input signal, 50% duty cycle, all loading with 50ý to VCC–2V, unless otherwise stated.
10. Bank A (pass-through) maximum frequency is limited by the output stage. Bank B (input-to-output ÷2, ÷4, ÷8, ÷16) can accept an input frequency
>3GHz, while Bank A will be slew rate limited.
11. Skew is measured between outputs under identical transitions.
12. Cycle-to-cycle jitter definition: the variation in 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.
13. Total jitter definition: with an ideal clock input, of frequency - 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
VCC/2
/RESET
tRR
IN
/IN
VIN Swing
tPD
/QB
VOUT Swing
QB
QA
/QA
M9999-082407
[email protected] or (408) 955-1690
5
Precision Edge®
SY89871U
Micrel, Inc.
TYPICAL OPERATING CHARACTERISTICS
VCC = 3.3V, VIN = 400mV, TA = 25°C, RL = 50ý to VCC–2V, unless otherwise stated.
IN to Q Propagation Delay
vs. Input Swing
QA Output Amplitude
vs. Frequency
900
700
600
500
400
300
200
800
700
600
500
400
300
200
100
0
3500
3000
2500
2000
1500
1000
0
0
500
100
700
PROPAGATION DELAY (ps)
PROPAGATION DELAY (ps)
800
QA AMPLITUDE (mV)
IN to Q Propagation Delay
vs. Temperature
900
0
200 400 600 800 1000 1200
INPUT SWING (mV)
600
500
400
300
-40 -20 0 20 40 60 80 100 120
TEMPERATURE (°C)
FREQUENCY (MHz)
QA@622MHz and [email protected]
622MHz Output
1.25GHz Output
QA
/Q
QB0
Output Swing
(100mV/div.)
Output Swing
(200mV/div.)
/QA
155.5MHz Output
÷4
Q
/QB0
TIME (1ns/div.)
TIME (100ps/div.)
2.5GHz Output
Output Swing
(100mV/div.)
/Q
Q
TIME (100ps/div.)
M9999-082407
[email protected] or (408) 955-1690
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Precision Edge®
SY89871U
Micrel, Inc.
DEFINITION OF SINGLE-ENDED AND DIFFERENTIAL SWING
VIN, VOUT
VDIFF_IN, VDIFF_OUT
800mV
(typical)
1600mV (typical)
Figure 1a. Single-Ended Swing
Figure 1b. Differential Swing
INPUT BUFFER STRUCTURE
VCC
VCC
1.86kΩ
1.86kΩ
25kΩ
R
S0
S1
/RESET
1.86kΩ
1.86kΩ
R
IN
50Ω
SY89871U
VT
50Ω
GND
GND
/IN
Figure 2a. Simplified Differential Input Buffer
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Figure 2b. Simplified TTL/CMOS Input Buffer
7
Precision Edge®
SY89871U
Micrel, Inc.
INPUT INTERFACE APPLICATIONS
VCC
VCC
VCC
VCC
VCC
VCC
IN
PECL
/IN
IN
IN
VCC
CML
CML
GND VCC
NC
VT
NC
VREF-AC
VREF-AC
NC
0.01µF
VCC
Rpd
VT
VREF-AC
Figure 3a. DC-Coupled CML
Input Interface
VT
SY89871U
SY89871U
GND
SY89871U
0.01µF
GND
/IN
/IN
Figure 3b. AC-Coupled CML
Input Interface
Note:
For 3.3V, Rpd = 50Ω.
For 2.5V, Rpd = 19Ω.
Figure 3c. DC-Coupled PECL
Input Interface
VCC
IN
VCC
VCC
VCC
VCC
PECL
/IN
Rpd
Rpd
VCC
GND
GND
SY89871U
Figure 3d. AC-Coupled PECL
Input Interface
/IN
/IN
SY89871U
SY89871U
VREF-AC
Note:
For 3.3V, Rpd = 100Ω.
For 2.5V, Rpd = 50Ω.
HSTL
LVDS
VT
0.01µF
IN
IN
GND
GND
NC
VT
NC
VREF-AC
VT
NC
VREF-AC
GND
Figure 3e. LVDS
Input Interface
Figure 3f. HSTL
Input Interface
RELATED PRODUCT AND SUPPORT DOCUMENTATION
Part Number
Function
Data Sheet Link
SY89874U
2.5GHz Any Diff. In-to-LVPECL Programmable
Clock Divider and 1:2 Fanout Buffer
w/Internal Termination
http://www.micrel.com/product-info/products/sy89874u.shtml
MLF® Application Note
http://www.amkor.com/products/notes_papers/mlf_appnote.pdf
HBW Solutions New Products and Applications
M9999-082407
[email protected] or (408) 955-1690
http://www.micrel.com/product-info/products/solutions.shtml
8
Precision Edge®
SY89871U
Micrel, Inc.
LVPECL OUTPUT TERMINATION RECOMMENDATIONS
+3.3V
+3.3V
ZO = 50Ω
R1
130Ω
R1
130Ω
R2
82Ω
R2
82Ω
+3.3V
ZO = 50Ω
Vt = VCC —2V
Figure 4a. Parallel Termination–Thevenin Equivalent
Note:
1. For +2.5V systems: R1 = 250ý, R2 = 62.5ý.
+3.3V
+3.3V
Z = 50Ω
Z = 50Ω
50Ω
50Ω
“destination”
“source”
VCC
50Ω
Rb
C1 (optional)
0.01µF
Figure 4b. Three-Resistor “Y–Termination”
Notes:
1. Power-saving alternative to Thevenin termination.
2. Place termination resistors as close to destination inputs as possible.
3. Rb resistor sets the DC bias voltage, equal to VT. For +3.3V systems Rb = 46ý to 50ý. For +2.5V systems Rb = 19ý.
4. C1 is an optional bypass capacitor intended to compensate for any tr/tf mismatches.
+3.3V
+3.3V
Q
+3.3V
R1
130Ω
R1
130Ω
Vt = VCC —1.3V
R3
+3.3V
1kΩ
ZO = 50Ω
/Q
R4
1.6kΩ
Vt = VCC —2V
R2
82Ω
R2
82Ω
Figure 4d. Terminating Unused I/O
Notes:
1. Unused output (/Q) must be terminated to balance the output.
2. For +2.5V systems: R1 = 250ý, R2 = 62.5ý, R3 = 1.25ký, R4 = 1.2ký.
M9999-082407
[email protected] or (408) 955-1690
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Precision Edge®
SY89871U
Micrel, Inc.
16-PIN MicroLeadFrame® (MLF-16)
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:
1. Package meets Level 2 moisture sensitivity classification, and is shipped in dry-pack form.
2. 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 data sheet 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.
© 2005 Micrel, Incorporated.
M9999-082407
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