MICREL SY89825UHI

2.5/3.3V 1:22 HIGH-PERFORMANCE,
ClockWorks™
LOW-VOLTAGE PECL BUS CLOCK DRIVER
SY89825U
& TRANSLATOR w/ INTERNAL TERMINATION
FINAL
FEATURES
DESCRIPTION
■ LVPECL or LVDS input to 22 LVPECL outputs
The SY89825U is a High Performance Bus Clock Driver
with 22 differential LVPECL output pairs. This part is
designed for use in low voltage (2.5V, 3.3V) applications
which require a large number of outputs to drive precisely
aligned, ultra low skew signals to their destination. The
input is multiplexed from either LVDS or LVPECL by the
CLK_SEL pin. The LVDS input includes a 100Ω internal
termination, thus eliminating the need for external
termination. The Output Enable (OE) is synchronous so
that the outputs will only be enabled/disabled when they
are already in the LOW state. This eliminates any chance
of generating a runt clock pulse when the device is enabled/
disabled as can happen with an asynchronous control.
The SY89825U features low pin-to-pin skew (35ps max.)
—performance previously unachievable in a standard
product having such a high number of outputs. The
SY89825U is available in a single space saving package
which provides a lower overall cost solution. In addition, a
single chip solution improves timing budgets by eliminating
the multiple device solution with their corresponding large
part-to-part skew.
■ 100K ECL compatible outputs
■ LVDS input includes 100Ω termination
■ Guaranteed AC parameters over voltage:
■
■
■
PIN CONFIGURATION
VCCO
/Q6
Q6
/Q5
Q5
/Q4
Q4
/Q3
Q3
/Q2
Q2
/Q1
Q1
/Q0
Q0
VCCO
64 63 62 61 60 59 58 57 56 55 54 53 52 51 50 49
VCCO
NC
NC
VCCI
LVDS_CLK
/LVDS_CLK
CLK_SEL
LVPECL_CLK
/LVPECL_CLK
GND
OE
NC
NC
/Q21
Q21
VCCO
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
64-Pin
EPAD-TQFP
(Top View)
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
VCCO
Q7
/Q7
Q8
/Q8
Q9
/Q9
Q10
/Q10
Q11
/Q11
Q12
/Q12
Q13
/Q13
VCCO
APPLICATIONS
■ High-performance PCs
■ Workstations
■ Parallel processor-based systems
■ Other high-performance computing
■ Communications
17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32
VCCO
/Q20
Q20
/Q19
Q19
/Q18
Q18
/Q17
Q17
/Q16
Q16
/Q15
Q15
/Q14
Q14
VCCO
■
• > 2GHz fMAX (toggle)
• < 35ps max. ch-ch skew
Low voltage operation: 2.5V, 3.3V
Temperature range: –40°C to +85°C
Output enable pin
Available in a 64-Pin EPAD-TQFP
Rev.: A
1
Amendment: /0
Issue Date: September 2001
ClockWorks™
SY89825U
Micrel
LOGIC SYMBOL
PIN NAMES
Pin
Function
CLK_SEL
LVDS_CLK,
/LVDS_CLK
Differential LVDS Inputs
(Internal 100Ω termination included)
LVDS_CLK
LVPECL_CLK,
/LVPECL_CLK
Differential LVPECL Inputs.
/LVDS_CLK
0
22
Q0 - Q21
22
CLK_SEL
Input CLK Select (LVTTL)
OE
Output Enable (LVTTL)
LVPECL_CLK
Q0 – Q21, /Q0 – /Q21
Differential LVPECL Outputs.
Terminate with 50Ω to VCC-2V
/LVPECL_CLK
GND
Ground
VCCI
Power Supply. Connect to
VCC on PCB. VCCI and VCCO are not
internally connected
VCCO
Power Supply for Output Buffer.
Connect to VCCI on PCB. VCCI and
VCCO are not internally connected
/Q0 - /Q21
1
LEN
Q
OE
TRUTH TABLE
D
SIGNAL GROUPS
OE(1)
CLK_SEL
Q0 – Q21
/Q0 – /Q21
0
0
LOW
HIGH
LVDS_CLK, /LVDS_CLK
0
1
LOW
HIGH
Q0 – Q21, /Q0 – /Q21
1
0
LVDS_CLK
/LVDS_CLK
1
1
LVPECL_CLK
/LVPECL_CLK
Signal
I/O
Input
Level
LVDS
Output
LVPECL
LVPECL_CLK, /LVPECL_CLK
Input
LVPECL
CLK_SEL, OE
Input
LVCMOS/LVTTL
NOTE:
1. The OE (output enable) signal is synchronized with the low level of the
LVDS_CLK and LVPECL_CLK signal.
ABSOLUTE MAXIMUM RATINGS(1)
Symbol
Rating
Value
Unit
VCCI / VCCO
VCC Pin Potential to Ground Pin
–0.5 to +4.0
V
VIN
Input Voltage
–0.5 to VCCI
V
IOUT
DC Output Current
–50
mA
Tstore
Storage Temperature
–65 to +150
°C
θJA
Package Thermal Resistance (Junction-to-Ambient)
With exposed pad soldered to GND
– Still-Air (multi-layer PCB)
– 200lfpm (multi-layer PCB)
– 500lfpm (multi-layer PCB)
23
18
15
°C/W
°C/W
°C/W
44
36
30
°C/W
°C/W
°C/W
4.3
°C/W
Exposed pad not soldered to GND
θJC
– Still-Air (multi-layer PCB)
– 200lfpm (multi-layer PCB)
– 500lfpm (multi-layer PCB)
Package Thermal Resistance
(Junction-to-Case)
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 book. Exposure to ABSOLUTE MAXIMUM RATING conditions
for extended periods may affect device reliability.
2
ClockWorks™
SY89825U
Micrel
DC ELECTRICAL CHARACTERISTICS
Power Supply
TA = –40°C
Symbol
Parameter
TA = +25°C
TA = +85°C
Min.
Typ.
Max.
Min.
Typ.
Max.
Min.
Typ.
Max.
Unit
VCCI,
VCCO
Power
Supply(1)
2.37
—
3.6
2.37
—
3.8
2.37
—
3.6
V
ICC
Total Supply Current(2)
—
100
150
—
100
150
—
100
150
mA
NOTES:
1. VCCI and VCCO must be connected together on the PCB such that they remain at the same potential. VCCI and VCCO are not internally connected on the die.
2. No load. Outputs floating.
LVDS Input (VCC = 2.37V to 3.6V, GND = 0V)
TA = –40°C
Symbol
Parameter
VIN
Input Voltage Range
VID
Differential Input Swing
Current(1)
IIL
Input Low
RIN
LVDS Differential Input Resistance
(LVDS_CLK to /LVDS_CLK)
TA = +25°C
TA = +85°C
Min.
Typ.
Max.
Min.
Typ.
Max.
Min.
Typ.
Max.
Unit
0
—
2.4
0
—
2.4
0
—
2.4
V
100
—
—
100
—
—
100
—
—
mV
–1.25
—
—
–1.25
—
—
–1.25
—
—
mA
80
100
120
80
100
120
80
100
120
Ω
NOTE:
1. For IIL, both LVDS inputs are grounded.
LVPECL Input/Output (VCC = 2.37V to 3.6V, GND = 0V)
TA = –40°C
Symbol
Parameter
TA = +25°C
TA = +85°C
Min.
Max.
Min.
Max.
Min.
Max.
Unit
VIH
Input HIGH Voltage
(Single ended)
VCC – 1.165
VCC – 0.88
VCC – 1.165
VCC – 0.88
VCC – 1.165
VCC – 0.88
V
VIL
Input LOW Voltage
VCC – 1.945
VCC – 1.625 VCC – 1.945
VCC – 1.625
VCC – 1.945
VCC – 1.625
V
Swing(1)
VPP
Minimum Input
LVPECL_CLK
600
—
600
—
600
—
mV
VCMR
Common Mode Range(2)
LVPECL_CLK
–1.5
–0.4
–1.5
–0.4
–1.5
–0.4
V
VOH
Output HIGH Voltage(3)
VCCO – 1.085 VCCO – 0.880 VCCO – 1.025 VCCO – 0.880 VCCO – 1.025 VCCO – 0.880
VOL
Output LOW
Voltage(3)
VCCO – 1.830 VCCO – 1.555 VCCO – 1.810 VCCO – 1.620 VCCO – 1.810 VCCO – 1.620
IIH
Input HIGH Current
—
150
—
150
—
150
µA
IIL
Input LOW Current
0.5
—
0.5
—
0.5
—
µA
V
V
NOTES:
1. The VPP (min.) is defined as the minimum input differential voltage which will cause no increase in the propagation delay.
2. VCMR is defined as the range within which the VIH level may vary, with the device still meeting the propagation delay specification. The numbers in the table are
referenced to VCCI. The VIL level must be such that the peak-to-peak voltage is less than 1.0V and greater than or equal to VPP (min.). The lower end of the
CMR range varies 1:1 with VCCI. The VCMR (min) will be fixed at 3.3V – |VCMR (min)|.
3. Outputs loaded with 50Ω to VCC -2V.
LVCMOS/LVTTL Control Inputs (OE, CLK_SEL) (VCC = 2.37V to 3.6V, GND = 0V)
TA = –40°C
Symbol
Parameter
TA = +25°C
TA = +85°C
Min.
Typ.
Max.
Min.
Typ.
Max.
Min.
Typ.
Max.
Unit
VIH
Input HIGH Voltage
2.0
—
—
2.0
—
—
2.0
—
—
V
VIL
Input LOW Voltage
—
—
0.8
—
—
0.8
—
—
0.8
V
IIH
Input HIGH Current
+20
—
–250
+20
—
–250
+20
—
–250
µA
IIL
Input LOW Current
—
—
–600
—
—
–600
—
—
–600
µA
3
ClockWorks™
SY89825U
Micrel
AC ELECTRICAL CHARACTERISTICS(1)
VCC = 2.37V to 3.6V, GND = 0V
TA = –40°C
Symbol
Parameter
Frequency(2)
fMAX
Max Toggle
tPHL
tPLH
Propagation Delay
(Differential)(3)
LVPECL IN
LVDS IN
tSKEW
Within-Device Skew(4)
Part-to-Part
Skew(5)
TA = +25°C
TA = +85°C
Min.
Typ.
Max.
Min.
Typ.
Max.
Min.
Typ.
Max.
Unit
2
—
—
2
—
—
2
—
—
GHz
0.600
0.800
—
—
1.2
1.4
0.600
0.800
0.900
1.1
1.2
1.4
0.600
0.800
—
—
1.2
1.4
—
—
35
—
20
35
—
—
35
ns
ps
—
100
200
—
100
200
—
100
200
ps
tS(OE)
OE Set-Up Time(6)
1.0
—
—
1.0
—
—
1.0
—
—
ns
tH(OE)
OE Hold Time(6)
0.5
—
—
0.5
—
—
0.5
—
—
ns
tr
tf
Output Rise/Fall Time
(20% – 80%)
300
—
600
300
450
600
300
—
600
ps
—
—
1.2
—
—
1.2
—
—
1.2
ns
t(switchover) Input Switchover
CLK_SEL-to-valid output
NOTES:
1. Outputs loaded with 50Ω to VCC – 2V. Airflow ≥ 300lfpm.
2. fMAX is defined as the maximum toggle frequency measured. Measured with a 750mV input signal, all loading with 50Ω to VCC –2V.
3. Differential propagation delay is defined as the delay from the crossing point of the differential input signals to the crossing point of the differential
output signals.
4. The within-device skew is defined as the worst case difference between any two similar delay paths within a single device operating at the same
voltage and temperature.
5. The part-to-part skew is defined as the absolute worst case difference between any two delay paths on any two devices operating at the same
voltage and temperature. Part-to-part skew is the total skew difference; pin-to-pin skew + part-to-part skew.
6. Set-up and hold time applies to synchronous applications that intend to enable/disable before the next clock cycle. For asynchronous applications,
set-up and hold time does not apply. OE set-up time is defined with respect to the rising edge of the clock. OE HIGH to LOW transition ensures
outputs remain disabled during the next clock cycle. OE LOW to HIGH transition enables normal operation of the next input clock.
PRODUCT ORDERING CODE
4
Ordering
Code
Package
Type
Operating
Range
Package
Marking
SY89825UHI
H64-1
Industrial
SY89825UHI
ClockWorks™
SY89825U
Micrel
LVDS/LVPECL INPUTS
VCC
VCC
1.9k
1.9k
75k
LVPECL_CLK
1.9k
75k
75k
1.9k
VIN
100Ω
VIN
/LVPECL_CLK
GND
GND
LVPECL Input Stage
LVDS Input Stage
Figure 1. Simplified LVPECL & LVDS Input Stage
5
ClockWorks™
SY89825U
Micrel
TYPICAL CHARACTERISTICS
Frequency Response
vs. Output Amplitude
Frequency Response
vs. Output Amplitude
900
300
4000
3500
0
FREQUENCY (MHz)
3000
200
100
4000
3500
3000
2500
2000
1500
0
100
1000
200
400
2500
300
500
2000
400
600
1500
500
700
1000
600
VSUP = 3.3V
VDIFFIN = 800mV
800
500
700
OUTPUT AMPLITUDE (mV)
VSUP = 2.5V
VDIFFIN = 800mV
800
500
OUTPUT AMPLITUDE (mV)
900
FREQUENCY (MHz)
Frequency Response
vs. Output Amplitude @2.5V
Frequency Response
vs. Output Amplitude @3.3V
6
ClockWorks™
SY89825U
Micrel
LVPECL TERMINATION RECOMMENDATIONS
down resistor at the output of each driver. The emmiter follower
outputs requires a DC current path to GND. Unused outputs can be
left floating with minimal impact on skew and jitter.
Output Considerations
Be sure to properly terminate all outputs as shown below, or
equivalent. For AC coupled applications, be sure to include a pull
+3.3V
R1
130Ω
R1
130Ω
+3.3V
ZO = 50Ω
+3.3V
ZO = 50Ω
R2
82Ω
R2
82Ω
Vt = VCC —2V
Figure 1. Parallel Termination–Thevenin Equivalent
Notes:
1. For +2.5V systems:
R1 = 250Ω
R2 = 62.5Ω
+3.3V
+3.3V
Z = 50Ω
“source”
“destination”
Z = 50Ω
50Ω
46Ω to 49Ω
50Ω
Rb
Figure 2. 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 = 46Ω to 49Ω.
4. Precision, low-cost 3-Resistor networks are available from resistor manufacturers such as Thin Film Technology (www.thinfilm.com).
7
ClockWorks™
SY89825U
Micrel
64 LEAD EPAD-TQFP (DIE UP) (H64-1)
12.00 0.472 BSC SQ.
1.00 +0.05
–0.05
0.039 +0.002
–0.002
4
10.00 0.394 BSC SQ.
4.50
0.177
+0.05
–0.05
+0.012
–0.012
48
64
6
DETAIL "A"
0° MIN.
6 7
0.20 0.008
0.09 0.004
0.15 0.006
0.05 0.002
48
0°- 7°
4.50 +0.03
–0.03
0.177+0.012
–0.012
0.60 +0.15
–0.15
0.024 +0.006
–0.006
1.00 0.039 REF.
33
16
17
32
5
0.50 0.020
1.20 0.047 MAX
SEE DETAIL "A"
BSC
0.01 0.004
7
0.22 +0.05
–0.05
0.009 +0.002
–0.002
Rev. 03
MICREL-SYNERGY 3250 SCOTT BOULEVARD
TEL
+ 1 (408) 980-9191
FAX
SANTA CLARA CA 95054
+ 1 (408) 914-7878
WEB
USA
http://www.micrel.com
This information is believed to be accurate and reliable, however no responsibility is assumed by Micrel for its use nor for any infringement of patents or
other rights of third parties resulting from its use. No license is granted by implication or otherwise under any patent or patent right of Micrel Inc.
© 2001 Micrel Incorporated
8