ICS ICS8725Y

PRELIMINARY
ICS8725
Integrated
Circuit
Systems, Inc.
1-TO-5
DIFFERENTIAL-TO-LVHSTL ZERO DELAY BUFFER
GENERAL DESCRIPTION
FEATURES
The ICS8725 is a high performance LVHSTL
zero delay buffer and a member of the
HiPerClockS™
HiPerClockS™ family of High Performance
Clocks Solutions from ICS. The VCO operates
at a frequency range of 250MHz to 500MHz.
Utilizing one of the outputs as feedback to the PLL output
frequencies up to 500MHz can be regenerated with zero
delay with respect to the input. Dual reference clock inputs
support redundant clock or multiple reference applications.
• Fully integrated PLL
,&6
• 5 LVHSTL outputs each with the ability to drive 50Ω to
ground
• Voh (max) = 1.2V
• 31.25MHz to 500MHz output frequency range
• Spread Smart™ for regenerating spread spectrum clocks
• Differential reference clock inputs accept any differential
input signal
•· Differential reference clock inputs will accept single ended
input signal with one of the inputs biased with a resistor
network
• 31.25MHz to 622MHz input frequency range
• LVCMOS / LVTTL control inputs
• 3.3V core, 1.8V output operating supply voltage
• 32 lead low-profile QFP (LQFP), 7mm x 7mm x 1.4mm
package body, 0.8mm package lead pitch
• 0°C to 70°C ambient operating temperature
• Industrial temperature version available upon request
BLOCK DIAGRAM
PIN ASSIGNMENT
VDDO
nQ4
Q4
VEE
VEE
VDDA
VDDi
PLL_SEL
DIV_SEL0
32 31 30 29 28 27 26 25
DIV_SEL1
REF_CLK1
nREF_CLK1
0
REF_CLK2
nREF_CLK2
1
0
0
÷8
1
PLL
1
Q0
nQ0
Q1
nQ1
Q2
nQ2
Q3
nQ3
Q4
nQ4
÷1
÷2
÷4
÷8
REF_SEL
DIV_SEL0
1
24
VDDO
DIV_SEL1
2
23
Q3
REF_CLK1
3
22
nQ3
nREF_CLK1
4
21
Q2
REF_CLK2
5
20
nQ2
nREF_CLK2
6
19
Q1
REF_SEL
7
18
nQ1
MR
8
17
VDDO
REF_DIV
FB_IN
nFB_IN
ICS8725
9 10 11 12 13 14 15 16
VDDO
Q0
nQ0
VEE
REF_DIV
FB_IN
MR
nFB_IN
VDDI
PLL_SEL
32-Lead LQFP
Y Package
Top View
The Preliminary Information presented herein represents a product in prototyping or pre-production. The noted characteristics are based on initial
product characterization. Integrated Circuit Systems, Incorporated (ICS) reserves the right to change any circuitry or specifications without notice.
8725
www.icst.com/products/hiperclocks.html
1
REV. A MARCH 5, 2001
PRELIMINARY
ICS8725
Integrated
Circuit
Systems, Inc.
1-TO-5
DIFFERENTIAL-TO-LVHSTL ZERO DELAY BUFFER
TABLE 1. PIN DESCRIPTIONS
Number
Name
Type
1
DIV_SEL0
Input
2
DIV_SEL1
Input
3
REF_CLK1
Input
4
nREF_CLK1
Input
5
REF_CLK2
Input
6
nRE2_CLK2
Input
7
REF_SEL
Input
8
MR
Input
Description
Determines output divider valued in Table 3.
Pulldown
LVCMOS / LVTTL interface levels.
Determines output divider valued in Table 3.
Pulldown
LVCMOS / LVTTL interface levels.
Pulldown Non-inver ting differential clock input.
Pullup
Inver ting differential clock input.
Pulldown Non-inver ting differential clock input.
Pullup
Inver ting differential clock input.
Differential clock select input. When Low selects REF_CLK2 or
Pulldown
nREF_CLK2. When HIGH selects REF_CLK1 or nREF_CLK1.
Resets dividers and determine state of the outputs.
Pulldown
LVCMOS / LVTTL interface levels.
Input and core power supply pin. Connect to 3.3V.
9
VDDI
Power
10
nFB_IN
Input
11
FB_IN
Input
Pulldown Feedback input to phase detector for regenerating clocks with "zero delay".
12
13, 28,
29
REF_DIV
Input
Pulldown
VEE
Power
Ground pins. Connect to ground.
14, 15
nQ0,
Q0
Output
Differential clock outputs. 50Ω typical output impedance.
LVHSTL interface levels.
16. 17,
24, 25
VDDO
Power
Output power supply pins. Connect to 1.8V.
30
nQ1,
Q1
nQ2,
Q2
nQ3,
Q3
nQ4,
Q4
VDDA
31
PLL_SEL
Input
32
VDDI
Power
18, 19
20, 21
22, 23
26, 27
8725
Pullup
Output
Output
Output
Output
Power
Pullup
Feedback input to phase detector for regenerating clocks with "zero delay".
Differential clock outputs. 50Ω typical output impedance.
LVHSTL interface levels.
Differential clock outputs. 50Ω typical output impedance.
LVHSTL interface levels.
Differential clock outputs. 50Ω typical output impedance.
LVHSTL interface levels.
Differential clock outputs. 50Ω typical output impedance.
LVHSTL interface levels.
PLL power supply pin. Connect to 3.3V.
Selects between the PLL and the reference clock as the input to the
dividers. When HIGH select PLL. When LOW selects reference clock.
LVCMOS / LVTTL interface levels.
Output power supply pin. Connect to 3.3V.
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2
REV. A MARCH 5, 2001
PRELIMINARY
ICS8725
Integrated
Circuit
Systems, Inc.
1-TO-5
DIFFERENTIAL-TO-LVHSTL ZERO DELAY BUFFER
TABLE 2. PIN CHARACTERISTICS
Symbol
Parameter
Input
Capacitance
CIN
Test Conditions
Minimum
REF_CLK1,
nREF_CLK1,
REF_CLK2,
nREF_CLK2,
FB_IN, nFB_IN
DIV_SEL0,
DIV_SEL1,
REF_SEL,
REF_DIV
PLL_SEL, MR
Input
Pullup Resistor
Input
Pulldown Resistor
RPULLUP
RPULLDOWN
Typical
Maximum
Units
TBD
pF
TBD
pF
51
KΩ
51
KΩ
TABLE 3. CONTROL INPUTS FUNCTION TABLE
DIV_SEL1
DIV_SEL0
0
0
FREQUENCY (MHz)
MINIMUM
MAXIMUM
250
250
0
1
125
250
1
0
62.5
125
1
1
31.25
62.5
TABLE 4. PLL INPUT REFERENCE CHARACTERISTICS, VDDI=VDDA=3.3V±5%, VDDO=1.8V±5%, TA=0°C TO 70°C
Symbol
Parameter
fREF
Input Reference Frequency
Test Conditions
Minimum
20
Typical
Maximum
Units
250
MHz
tR
Input Rise Time
Measured at 20% to 80% points
TBD
ns
tF
Input Fall Time
Measured at 20% to 80% point
TBD
ns
tDC
Input Reference Duty Cycle
TBD
%
8725
TBD
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3
REV. A MARCH 5, 2001
PRELIMINARY
ICS8725
Integrated
Circuit
Systems, Inc.
1-TO-5
DIFFERENTIAL-TO-LVHSTL ZERO DELAY BUFFER
ABSOLUTE MAXIMUM RATINGS
Supply Voltage
4.6V
Inputs
-0.5V to VDD+0.5 V
Outputs
-0.5V to VDD+0.5V
Ambient Operating Temperature 0°C to 70°C
Storage Temperature
-65°C to 150°C
Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These ratings are
stress specifications only and functional operation of the device at these or any conditions beyond those listed in the DC Characteristics or AC Characteristics is not implied. Exposure to absolute maximum rating conditions for extended periods may affect product
reliability.
TABLE 5A. POWER SUPPLY DC CHARACTERISTICS, VDDI=VDDA=3.3V±5%, VDDO=1.8V±5%, TA=0°C TO 70°C
Symbol
Parameter
VDDI
VDDA
Test Conditions
Minimum
Typical
Maximum
Units
Input Power Supply Voltage
3.135
3.3
3.465
V
Analog Power Supply Voltage
3.135
3.3
3.465
V
VDDO
Output Power Supply Voltage
IEE
Power Supply Current
1.8
V
mA
TABLE 5B. DIFFERENTIAL DC CHARACTERISTICS, VDDI=VDDA=3.3V±5%, VDDO=1.8V±5%, TA=0°C TO 70°C
Symbol
Parameter
Test Conditions Minimum Typical Maximum Units
REF_CLK1, REF_CLK2,
VIN = 3.465V
150
µA
FB_IN
IIH
Input High Current
nREF_CLK1, nREF_CLK2,
VIN = 3.465V
5
µA
nFB_IN
REF_CLK1, REF_CLK2,
VIN = 0V
-5
µA
IIL
Input Low Current FB_IN
nREF1, nREF2, nFB_IN
VIN = 0V
-150
µA
NOTE: For REF_CLK1, nREF_CLK1 and REF_CLK2, nREF_CLK2 input levels, see VPP and VCMR in AC Characteristics
table.
TABLE 5C. LVCMOS DC CHARACTERISTICS, VDDI=VDDA=3.3V±5%, VDDO=1.8V±5%, TA=0°C TO 70°C
Symbol Parameter
VIH
Input High Voltage
VIL
Input Low Voltage
IIH
Input High Current
Test Conditions
DIV_SEL0, DIV_SEL1,
REF_SEL, PLL_SEL,
REF_DIV, MR
DIV_SEL0, DIV_SEL1,
REF_SEL, PLL_SEL,
REF_DIV, MR
DIV_SEL0, DIV_ SEL1,
REF_DIV, REF_SEL, MR
PLL_SEL
IIL
8725
Input Low Current
Minimum
Typical
Maximum
Units
2
3.765
V
-0.3
0.8
V
VIN = 3.465V
150
µA
VIN = 3.465V
5
µA
DIV_SEL0, DIV_ SEL1,
REF_DIV, REF_SEL, MR
VIN = 0V
-5
µA
PLL_SEL
VIN = 0V
-150
µA
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4
REV. A MARCH 5, 2001
PRELIMINARY
Integrated
Circuit
Systems, Inc.
ICS8725
1-TO-5
DIFFERENTIAL-TO-LVHSTL ZERO DELAY BUFFER
TABLE 5D. LVHSTL DC CHARACTERISTICS, VDDI=VDDA=3.3V±5%, VDDO=1.8V±5%, TA=0°C TO 70°C
Symbol
Parameter
VOH
Output High Voltage; NOTE 1
VOL
Output Low Voltage; NOTE 1
Test Conditions
Minimum
Typical
Maximum
Units
1.2
V
1.0
0
0.4
40% x (VOH-VOL)
60% x (VOH-VOL)
VOX
Output Crossover Voltage
+ VOL
+ VOL
NOTE 1: Outputs terminated with 50Ω to ground. The power dissipation of a terminated output pair is 32mW.
V
V
TABLE 6. AC CHARACTERISTICS, VDDI=VDDA=3.3V±5%, VDDO=1.8V±5%, TA=0°C TO 70°C
Symbol Parameter
Test Conditions
Minimum
Typical
Maximum
Units
500
MHz
fMAX
Maximum Output Frequency
VPP
Peak-to-Peak Input Voltage
f = 500MHz
Common Mode Input Voltage
f = 500MHz
Propagation Delay,
Low-to-High
Propagation Delay,
High-to-Low
REF_CLK1,
PLL Reference
nREF_CLK1
Zero Delay;
REF_CLK2,
NOTE 2
nREF_CLK2
PLL_SEL=0V, 0MHz ≤ f ≤ 500MHz
TBD
TBD
ns
PLL_SEL=0V, 0MHz ≤ f ≤ 500MHz
TBD
TBD
ns
PLL_SEL=3.3V, fREF=TBD,
fVCO=TBD
-100
100
ps
100
ps
VCMR
tpLH
tpHL
t(Ø)
Measured on rising edge at
VDDO/2
Measured on rising edge at
VDDO/2
TBD
tsk(o)
Output Skew; NOTE 3
tjit(cc)
Cycle-to-Cycle Jitter
tL
PLL Lock Time
tR
Output Rise Time
TBD
TBD
ps
tF
Output Fall Time
TBD
TBD
ps
tPW
Output Pulse Width
±100
ps
TBD
0MHz ≤ f ≤ 500MHz
tCYCLE/2
-TBD
tCYCLE/2
tCYCLE/2
+TBD
ns
f = 500MHz
TBD
2.08
TBD
ns
tEN
Output Enable Time
TBD
ns
tDIS
Output Disable Time
TBD
ns
NOTE 1: All parameters measured at fMAX unless noted otherwise. All outputs terminated with 50Ω to VDDO/2.
NOTE 2: Defined as the time difference between the input reference clock and the averaged feedback input signal
when the PLL is locked and the input reference frequency is stable.
NOTE 3: Defined as skew across banks of outputs at the same supply voltages and with equal load conditions.
NOTE 4: Defined as the variation in cycle time of a signal between adjacent cycles, over a random sample of adjacent pairs
of cycles.
8725
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5
REV. A MARCH 5, 2001
PRELIMINARY
ICS8725
Integrated
Circuit
Systems, Inc.
1-TO-5
DIFFERENTIAL-TO-LVHSTL ZERO DELAY BUFFER
PACKAGE OUTLINE - Y SUFFIX
D
D2
θ
E
25
24
32
1
2
3
L
E1
E2
N
8
17
16
9
e
A
D1
A2
-Cccc C
b
A1
SEATING
PLANE
c
TABLE 7. PACKAGE DIMENISIONS
JEDEC VARIATION
ALL DIMENSIONS IN MILLIMETERS
BBA
SYMBOL
MINIMUM
NOMINAL
32
N
1.60
A
A1
MAXIMUM
0.05
0.15
A2
1.35
1.40
1.45
b
0.30
0.37
0.45
c
0.09
0.20
D
9.00 BASIC
D1
7.00 BASIC
D2
5.60
E
9.00 BASIC
E1
7.00 BASIC
E2
5.60
e
0.80 BASIC
L
0.45
q
0°
0.60
0.75
7°
0.10
ccc
Reference Document: JEDEC Publication 95, MS-026
8725
www.icst.com/products/hiperclocks.html
6
REV. A MARCH 5, 2001
PRELIMINARY
ICS8725
Integrated
Circuit
Systems, Inc.
1-TO-5
DIFFERENTIAL-TO-LVHSTL ZERO DELAY BUFFER
TABLE 8. ORDERING INFORMATION
Part/Order Number
Marking
Package
Count
Temperature
ICS8725Y
ICS87251
32 Lead LQFP
250 per tray
0°C to 70°C
ICS8725YT
ICS8725
32 Lead LQFP on Tape and Reel
2000
0°C to 70°C
While the information presented herein has been checked for both accuracy and reliability, Integrated Circuit Systems, Incorporated (ICS) assumes no responsibility for either its use or
for infringement of any patents or other rights of third parties, which would result from its use. No other circuits, patents, or licenses are implied. This product is intended for use in normal
commercial applications. Any other applications such as those requiring extended temperature range, high reliability, or other extraordinary environmental requirements are not
recommended without additional processing by ICS. ICS reserves the right to change any circuitry or specifications without notice. ICS does not authorize or warrant any ICS product for
use in life support devices or critical medical instruments.
8725
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7
REV. A MARCH 5, 2001