ICS ICS8430DY-111T

PRELIMINARY
Integrated
Circuit
Systems, Inc.
ICS8430-111
700MHZ, LOW JITTER
DIFFERENTIAL-TO-3.3V LVPECL FREQUENCY SYNTHESIZER
GENERAL DESCRIPTION
FEATURES
The ICS8430-111 is a general purpose, dual outICS
put high frequency synthesizer and a member of
HiPerClockS™
the HiPerClockS™ family of High Performance
Clock Solutions from ICS. The CLK, nCLK pair
can accept most standard differential input levels. The single ended TEST_CLK input accepts LVCMOS or
LVTTL input levels and translates them to 3.3V LVPECL levels.
The VCO operates at a frequency range of 200MHz to 700MHz.
With the output configured to divide the VCO frequency by 2,
output frequency steps as small as 2MHz can be achieved
using a 16MHz differential or single ended reference clock. Output frequencies up to 700MHz can be programmed using the
serial or parallel interfaces to the configuration logic. The low
jitter and frequency range of the ICS8430-111 makes it an ideal
clock generator for most clock tree applications.
• Dual differential 3.3V LVPECL output
• Selectable 14MHz to 27MHz differential CLK, nCLK
or TEST_CLK input
• CLK, nCLK accepts any differential input signal:
LVPECL, LVHSTL, LVDS, SSTL, HCSL
• TEST_CLK accepts the following input types:
LVCMOS, LVTTL
• Output frequency range up to 700MHz
• VCO range: 200MHz to 700MHz
• Parallel or serial interface for programming counter
and output dividers
• Cycle-to-cycle jitter: 25ps (maximum)
• 3.3V supply voltage
• 0°C to 70°C ambient operating temperature
• Industrial termperature information available upon request
BLOCK DIAGRAM
PIN ASSIGNMENT
nCLK
nP_LOAD
M0
M1
32 31 30 29 28 27 26 25
1
÷ 16
PLL
PHASE DETECTOR
MR
VCO
÷M
0
1
1
24
CLK
M6
2
23
TEST_CLK
M7
3
22
CLK_SEL
M8
4
21
VCCA
N0
5
20
S_LOAD
N1
6
19
S_DATA
N2
7
18
S_CLOCK
VEE
8
17
MR
ICS8430-111
9 10 11 12 13 14 15 16
VEE
nFOUT0
FOUT0
VCCO
nFOUT1
FOUT1
VCC
CONFIGURATION
INTERFACE
LOGIC
M5
TEST
FOUT0
nFOUT0
FOUT1
nFOUT1
÷N
÷2
S_LOAD
S_DATA
S_CLOCK
nP_LOAD
M2
0
M3
CLK
nCLK
M4
CLK_SEL
TEST_CLK
VCO_SEL
VCO_SEL
TEST
32-Lead LQFP
7mm x 7mm x 1.4mm package body
Y Package
Top View
M0:M8
N0:N2
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.
8430DY-111
www.icst.com/products/hiperclocks.html
1
REV. F JUNE 1, 2005
PRELIMINARY
Integrated
Circuit
Systems, Inc.
ICS8430-111
700MHZ, LOW JITTER
DIFFERENTIAL-TO-3.3V LVPECL FREQUENCY SYNTHESIZER
FUNCTIONAL DESCRIPTION
the parallel input mode. The relationship between the VCO frequency, the input frequency and the M divider is defined as
follows: fVCO = fIN x M
The ICS8430-111 features a fully integrated PLL and therefore requires no external components for setting the loop
bandwidth. A differential clock input is used as the input to the
on-chip oscillator. The output of the oscillator is divided by 16
prior to the phase detector. A16MHz clock input provides a
1MHz reference frequency. The VCO of the PLL operates over
a range of 200 to 700MHz. The output of the M divider is also
applied to the phase detector.
The M value and the required values of M0 through M8 are
shown in Table 3B, Programmable VCO Frequency Function
Table. Valid M values for which the PLL will achieve lock for a
16MHz reference are defined as 100 ≤ M ≤ 350. The frequency
out is defined as follows: fOUT = fVCO = fIN x M
N
N
Serial operation occurs when nP_LOAD is HIGH and S_LOAD
is LOW. The shift register is loaded by sampling the S_DATA
bits with the rising edge of S_CLOCK. The contents of the
shift register are loaded into the M divider and N output divider
when S_LOAD transitions from LOW-to-HIGH. The M divide
and N output divide values are latched on the HIGH-to-LOW
transition of S_LOAD. If S_LOAD is held HIGH, data at the
S_DATA input is passed directly to the M divider and N output
divider on each rising edge of S_CLOCK. The serial mode can
be used to program the M and N bits and test bits T1 and T0.
The internal registers T0 and T1 determine the state of the
The phase detector and the M divider force the VCO output
frequency to be 2M times the reference frequency by adjusting the VCO control voltage. Note that for some values of M
(either too high or too low), the PLL will not achieve lock. The
output of the VCO is scaled by a divider prior to being sent to
each of the LVPECL output buffers. The divider provides a
50% output duty cycle.
The programmable features of the ICS8430-111 support two
input modes to program the M divider and N output divider.
The two input operational modes are parallel and serial. Figure 1 shows the timing diagram for each mode. In
parallel mode the nP_LOAD input is initially LOW. The data on
inputs M0 through M8 and N0 through N2 is passed directly
to the M divider and N output divider. On the LOW-to-HIGH
transition of the nP_LOAD input, the data is latched and the M
divider remains loaded until the next LOW transition on
nP_LOAD or until a serial event occurs. As a result, the M
and N bits can be hardwired to set the M divider and N output
divider to a specific default state that will automatically occur
during power-up. The TEST output is LOW when operating in
T1
T0
TEST Output
0
0
LOW
0
1
S_Data, Shift Register Input
1
0
Output of M divider
1
1
CMOS Fout
SERIAL LOADING
S_CLOCK
S_DATA
t
S_LOAD
S
t
H
nP_LOAD
t
S
PARALLEL LOADING
M, N
M0:M8, N0:N1
nP_LOAD
t
S
t
H
S_LOAD
Time
FIGURE 1. PARALLEL & SERIAL LOAD OPERATIONS
*NOTE:
8430DY-111
The NULL timing slot must be observed.
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2
REV. F JUNE 1, 2005
PRELIMINARY
Integrated
Circuit
Systems, Inc.
ICS8430-111
700MHZ, LOW JITTER
DIFFERENTIAL-TO-3.3V LVPECL FREQUENCY SYNTHESIZER
TABLE 1. PIN DESCRIPTIONS
Number
1, 2, 3,
28, 29, 30
31, 32
4
Name
M5, M6, M7,
M0, M1, M2,
M3, M4
M8
Input
5, 6
N0, N1
Input
7
8, 16
N2
VEE
Input
Power
9
TEST
Output
10
VCC
FOUT1,
nFOUT1
VCCO
FOUT0,
nFOUT0
Power
11, 12
13
14, 15
Type
Input
Description
Pulldown M divider inputs. Data latched on LOW-to-HIGH transition
of nP_LOAD input. LVCMOS/LVTTL interface levels.
Pullup
Pulldown Determines output divider value as defined in Table 3C
Function Table. LVCMOS/LVTTL interface levels.
Pullup
Negative supply pins.
Test output which is ACTIVE in the serial mode of operation.
Output driven LOW in parallel mode. LVCMOS/LVTTL interface levels.
Core supply pin.
Output
Differential output for the synthesizer. 3.3V LVPECL interface levels.
Power
Output supply pin.
Output
Differential output for the synthesizer. 3.3V LVPECL interface levels.
Active High Master Reset. When logic HIGH, the internal dividers
are reset causing the true outputs FOUTx to go low and the inver ted
17
MR
Input
Pulldown outputs nFOUTx to go high. When logic LOW, the internal dividers
and the outputs are enabled. Asser tion of MR does not affect loaded
M, N, and T values. LVCMOS / LVTTL interface levels.
Clocks in serial data present at S_DATA input into the shift register
18
S_CLOCK
Input
Pulldown
on the rising edge of S_CLOCK. LVCMOS/LVTTL interface levels.
Shift register serial input. Data sampled on the rising edge of
19
S_DATA
Input
Pulldown
S_CLOCK. LVCMOS/LVTTL interface levels.
Controls transition of data from shift register into the dividers.
20
S_LOAD
Input
Pulldown
LVCMOS/LVTTL interface levels.
Power
Analog supply pin.
21
VCCA
Selects between differential clock or test inputs as the PLL reference
source. Selects CLK, nCLK inputs when HIGH. Selects TEST_CLK
22
Input
Pullup
CLK_SEL
when LOW. LVCMOS/LVTTL interface levels.
Pulldown Test clock input. LVCMOS/LVTTL interface levels.
23
TEST_CLK
Input
24
CLK
Input
Pulldown Non-inver ting differential clock input.
nCLK
Input
Pullup
Inver ting differential clock input.
25
Parallel load input. Determines when data present at M8:M0 is
26
nP_LOAD
Input
Pulldown loaded into the M divider, and when data present at N2:N0 sets
the N output divider value. LVCMOS/LVTTL interface levels.
Determines whether synthesizer is in PLL or bypass mode.
27
VCO_SEL
Input
Pullup
LVCMOS/LVTTL interface levels.
NOTE: Pullup and Pulldown refer to internal input resistors. See Table 2, Pin Characteristics, for typical values.
TABLE 2. PIN CHARACTERISTICS
Symbol
CIN
RPULLUP
RPULLDOWN
8430DY-111
Parameter
Input Capacitance
Input Pullup Resistor
Input Pulldown Resistor
Test Conditions
Minimum
Typical
51
51
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3
Maximum
4
Units
pF
kΩ
kΩ
REV. F JUNE 1, 2005
PRELIMINARY
Integrated
Circuit
Systems, Inc.
TABLE 3A. PARALLEL
AND
ICS8430-111
700MHZ, LOW JITTER
DIFFERENTIAL-TO-3.3V LVPECL FREQUENCY SYNTHESIZER
SERIAL MODE FUNCTION TABLE
Inputs
Conditions
MR
nP_LOAD
M
N
S_LOAD
S_CLOCK
S_DATA
H
X
X
X
X
X
X
Reset. Forces outputs LOW.
L
L
Data
Data
X
X
X
Data on M and N inputs passed directly to the M
divider and N output divider. TEST output forced LOW.
L
↑
Data
Data
L
X
X
L
H
X
X
L
↑
Data
L
H
X
X
↑
L
Data
L
H
X
X
↓
L
Data
L
H
X
X
L
X
X
H
↑
Data
L
H
X
X
NOTE: L = LOW
H = HIGH
X = Don't care
↑ = Rising edge transition
↓ = Falling edge transition
Data is latched into input registers and remains loaded
until next LOW transition or until a serial event occurs.
Serial input mode. Shift register is loaded with data on
S_DATA on each rising edge of S_CLOCK.
Contents of the shift register are passed to the
M divider and N output divider.
M divider and N output divider values are latched.
Parallel or serial input do not affect shift registers.
S_DATA passed directly to M divider as it is clocked.
TABLE 3B. PROGRAMMABLE VCO FREQUENCY FUNCTION TABLE (NOTE 1)
100
256
M8
0
128
M7
0
64
M6
1
32
M5
1
16
M4
0
8
M3
0
4
M2
1
2
M1
0
1
M0
0
101
102
103
0
0
0
0
0
0
1
1
1
1
1
1
0
0
0
0
0
0
1
1
1
0
1
1
1
0
1
•
•
0
0
1
•
•
0
1
0
VCO Frequency
(MHz)
M Divide
200
202
204
206
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
696
34 8
1
0
1
0
1
1
1
698
349
1
0
1
0
1
1
1
700
35 0
1
0
1
0
1
1
1
NOTE 1: These M divide values and the resulting frequencies correspond to an input frequency of 16MHz.
TABLE 3C. PROGRAMMABLE OUTPUT DIVIDER FUNCTION TABLE
8430DY-111
N2
0
Input
N1
0
N0
0
0
0
1
4
50
175
0
1
0
8
25
87.5
N Divider Value
2
Output Frequency (MHz)
Minimum
Maximum
100
350
0
1
1
16
12.5
43.75
1
0
0
1
200
700
350
1
0
1
2
100
1
1
0
4
50
175
1
1
1
8
25
87.5
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4
REV. F JUNE 1, 2005
PRELIMINARY
Integrated
Circuit
Systems, Inc.
ICS8430-111
700MHZ, LOW JITTER
DIFFERENTIAL-TO-3.3V LVPECL FREQUENCY SYNTHESIZER
ABSOLUTE MAXIMUM RATINGS
Supply Voltage, VCC
4.6V
Inputs, VI
-0.5V to VCC + 0.5 V
Outputs, VO
-0.5V to VCCO + 0.5V
Package Thermal Impedance, θJA
47.9°C/W (0 lfpm)
Storage Temperature, TSTG
-65°C to 150°C
NOTE: Stresses beyond those listed under Absolute
Maximum Ratings may cause permanent damage to the
device. These ratings are stress specifications only. Functional
operation of product at these conditions 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 4A. POWER SUPPLY DC CHARACTERISTICS, VCC = VCCA = VCCO = 3.3V±5%, TA = 0°C TO 70°C
Symbol
Parameter
Test Conditions
Minimum
Typical
Maximum
Units
VCC
Core Supply
3.135
3.3
3.465
V
VCCA
Analog Voltage
3.135
3.3
3.465
V
VCCO
Ouput Voltage
3.135
3.3
3.465
V
IEE
Power Supply Current
120
mA
ICCA
Analog Supply Current
10
mA
TABLE 4B. LVCMOS/LVTTL DC CHARACTERISTICS, VCC = VCCA = VCCO = 3.3V±5%, TA = 0°C TO 70°C
Symbol
Parameter
Test Conditions
VIH
Input High Voltage
VIL
Input Low Voltage
M0-M7, N0, N1, MR,
S_CLOCK, S_DATA, S_LOAD,
Input
High Current TEST_CLK, nP_LOAD
M8, N2, CLK_SEL, VCO_SEL
M0-M7, N0, N1, MR,
S_CLOCK, S_DATA, S_LOAD,
Input
TEST_CLK, nP_LOAD
Low Current
M8, N2, CLK_SEL, VCO_SEL
IIH
IIL
Maximum
Units
2
VCC + 0.3
V
-0.3
0.8
V
VCC = VIN = 3.465V
150
µA
VCC = VIN = 3.465V
5
µA
VCC = 3.465V,
VIN = 0V
VCC = 3.465V,
VIN = 0V
Output
TEST; NOTE 1
High Voltage
Output
VOL
TEST; NOTE 1
Low Voltage
NOTE 1: Outputs terminated with 50Ω to VCCO/2.
VOH
8430DY-111
Minimum
Typical
-5
µA
-150
µA
2.6
V
0.5
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5
V
REV. F JUNE 1, 2005
PRELIMINARY
Integrated
Circuit
Systems, Inc.
ICS8430-111
700MHZ, LOW JITTER
DIFFERENTIAL-TO-3.3V LVPECL FREQUENCY SYNTHESIZER
TABLE 4C. DIFFERENTIAL DC CHARACTERISTICS, VCC = VCCA = VCCO = 3.3V±5%, TA = 0°C TO 70°C
Symbol
Parameter
Test Conditions
IIH
Input High Current
IIL
Input Low Current
Minimum
Typical
Maximum
Units
nCLK
VIN = VCC = 3.465V
5
µA
CLK
VIN = VCC = 3.465V
150
µA
nCLK
VIN = 0V, VCC = 3.465V
-150
CLK
VIN = 0V, VCC = 3.465V
-5
µA
µA
VPP
Peak-to-Peak Input Voltage
0.15
Common Mode Input Voltage;
VEE + 0.5
VCMR
NOTE 1, 2
NOTE 1: For single ended applications, the maximum input voltage for CLK, nCLK is VCC + 0.3V.
NOTE 2: Common mode voltage is defined as VIH.
1.3
V
VCC - 0.85
V
Maximum
Units
TABLE 4D. LVPECL DC CHARACTERISTICS, VCC = VCCA = VCCO = 3.3V±5%, TA = 0°C TO 70°C
Symbol
Parameter
Test Conditions
Minimum
Typical
VOH
Output High Voltage; NOTE 1
VCCO - 1.4
VCCO - 0.9
V
VOL
Output Low Voltage; NOTE 1
VCCO - 2.0
VCCO - 1.7
V
VSWING
Peak-to-Peak Output Voltage Swing
0.6
1.0
V
NOTE 1: Outputs terminated with 50Ω to VCCO - 2V. See 3.3V Output Load Test Circuit figure in the
Parameter Measurement Information section.
TABLE 5. INPUT FREQUENCY CHARACTERISTICS, VCC = VCCA = VCCO = 3.3V±5%, TA = 0°C TO 70°C
Symbol Parameter
fIN
Input Frequency
Maximum
Units
TEST_CLK; NOTE 1
Test Conditions
Minimum
14
Typical
27
MHz
CLK, nCLK; NOTE 1
14
27
MHz
S_CLOCK
50
MHz
NOTE1: For the differential input and reference frequency range, the M value must be set for the VCO to operate within
the 200MHz to 700MHz range. Using the minimum input frequency of 14MHz, valid values of M are 115 ≤ M ≤ 400.
Using the maximum frequency of 27MHz, valid values of M are 60 ≤ M ≤ 208.
8430DY-111
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6
REV. F JUNE 1, 2005
PRELIMINARY
Integrated
Circuit
Systems, Inc.
ICS8430-111
700MHZ, LOW JITTER
DIFFERENTIAL-TO-3.3V LVPECL FREQUENCY SYNTHESIZER
TABLE 6. AC CHARACTERISTICS, VCC = VCCA = VCCO = 3.3V±5%, TA = 0°C TO 70°C
Symbol
Parameter
FMAX
Output Frequency
Test Conditions
Minimum
Typical
fOUT > 87.5MHz
Maximum
Units
700
MHz
25
ps
tjit(cc)
Cycle-to-Cycle Jitter ; NOTE 1
40
ps
tjit(per)
Period Jitter, RMS
9.5
ps
tsk(o)
Output Skew; NOTE 1, 2
15
ps
tR / tF
Output Rise/Fall Time
700
ps
fOUT < 87.5MHz
20% to 80%
M, N to nP_LOAD
tS
tH
Setup Time
Hold Time
5
S_DATA to S_CLOCK
5
ns
5
ns
M, N to nP_LOAD
5
ns
S_DATA to S_CLOCK
5
ns
5
Output Duty Cycle
48
52
%
N=1
45
55
%
1
ms
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7
ns
N≠1
PLL Lock Time
tLOCK
See Parameter Measurement Information section.
NOTE 1:This parameter is defined in accordance with JEDEC Standard 65.
NOTE 2: Defined as skew between outputs at the same supply voltage and with equal load conditions.
Measured at the output differential cross points.
8430DY-111
ns
S_CLOCK to S_LOAD
S_CLOCK to S_LOAD
odc
200
REV. F JUNE 1, 2005
PRELIMINARY
Integrated
Circuit
Systems, Inc.
ICS8430-111
700MHZ, LOW JITTER
DIFFERENTIAL-TO-3.3V LVPECL FREQUENCY SYNTHESIZER
PARAMETER MEASUREMENT INFORMATION
VCC, VCCA , VCCO = 2V
VCC
Qx
SCOPE
nCLK
V
LVPECL
V
Cross Points
PP
CMR
CLK
nQx
VEE
VEE = -1.3V ± 0.165V
3.3V OUTPUT LOAD AC TEST CIRCUIT
DIFFERENTIAL INPUT LEVEL
nFOUTx
80%
80%
FOUTx
VSW I N G
Clock
Outputs
nFOUTy
20%
20%
tF
tR
FOUTy
tsk(o)
OUTPUT RISE/FALL TIME
OUTPUT SKEW
VOH
nFOUTx
VREF
FOUTx
➤
tcycle
➤
n
tcycle n+1
VOL
1σ contains 68.26% of all measurements
2σ contains 95.4% of all measurements
3σ contains 99.73% of all measurements
4σ contains 99.99366% of all measurements
6σ contains (100-1.973x10-7)% of all measurements
➤
➤
t jit(cc) = tcycle n –tcycle n+1
Reference Point
1000 Cycles
(Trigger Edge)
Histogram
Mean Period
(First edge after trigger)
PERIOD JITTER
CYCLE-TO-CYCLE JITTER
nFOUTx
FOUTx
t PW
t
odc =
PERIOD
t PW
x 100%
t PERIOD
OUTPUT DUTY CYCLE/PULSE WIDTH/PERIOD
8430DY-111
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8
REV. F JUNE 1, 2005
PRELIMINARY
Integrated
Circuit
Systems, Inc.
ICS8430-111
700MHZ, LOW JITTER
DIFFERENTIAL-TO-3.3V LVPECL FREQUENCY SYNTHESIZER
APPLICATION INFORMATION
POWER SUPPLY FILTERING TECHNIQUES
As in any high speed analog circuitry, the power supply pins
are vulnerable to random noise. The ICS8430-111 provides
separate power supplies to isolate any high switching
noise from the outputs to the internal PLL. VCC, VCCA, and VCCO
should be individually connected to the power supply
plane through vias, and bypass capacitors should be
used for each pin. To achieve optimum jitter performance,
power supply isolation is required. Figure 2 illustrates how
a 10Ω resistor along with a 10μF and a .01μF bypass
capacitor should be connected to each VCCA pin.
TERMINATION
FOR
3.3V
VCC
.01μF
10Ω
V CCA
.01μF
10 μF
FIGURE 2. POWER SUPPLY FILTERING
LVPECL OUTPUTS
drive 50Ω transmission lines. Matched impedance techniques
should be used to maximize operating frequency and minimize
signal distortion. There are a few simple termination schemes.
Figures 3A and 3B show two different layouts which are recommended only as guidelines. Other suitable clock layouts may
exist and it would be recommended that the board designers
simulate to guarantee compatibility across all printed circuit and
clock component process variations.
The clock layout topology shown below is a typical termination
for LVPECL outputs. The two different layouts mentioned are
recommended only as guidelines.
FOUT and nFOUT are low impedance follower outputs that
generate ECL/LVPECL compatible outputs. Therefore, terminating resistors (DC current path to ground) or current sources
must be used for functionality. These outputs are designed to
3.3V
Zo = 50Ω
125Ω
FOUT
FIN
Zo = 50Ω
Zo = 50Ω
FOUT
50Ω
1
RTT =
Z
((VOH + VOL) / (VCC – 2)) – 2 o
FIN
50Ω
Zo = 50Ω
VCC - 2V
VCC
- 2V
RTT
84Ω
FIGURE 3A. LVPECL OUTPUT TERMINATION
8430DY-111
125Ω
84Ω
FIGURE 3B. LVPECL OUTPUT TERMINATION
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9
REV. F JUNE 1, 2005
PRELIMINARY
Integrated
Circuit
Systems, Inc.
ICS8430-111
700MHZ, LOW JITTER
DIFFERENTIAL-TO-3.3V LVPECL FREQUENCY SYNTHESIZER
WIRING THE DIFFERENTIAL INPUT TO ACCEPT SINGLE ENDED LEVELS
of R1 and R2 might need to be adjusted to position the V_REF in
the center of the input voltage swing. For example, if the input
clock swing is only 2.5V and VCC = 3.3V, V_REF should be 1.25V
and R2/R1 = 0.609.
Figure 4 shows how the differential input can be wired to accept
single ended levels. The reference voltage V_REF = VCC/2 is
generated by the bias resistors R1, R2 and C1. This bias circuit
should be located as close as possible to the input pin. The ratio
VCC
R1
1K
Single Ended Clock Input
CLK
V_REF
nCLK
C1
0.1u
R2
1K
FIGURE 4. SINGLE ENDED SIGNAL DRIVING DIFFERENTIAL INPUT
8430DY-111
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10
REV. F JUNE 1, 2005
PRELIMINARY
Integrated
Circuit
Systems, Inc.
ICS8430-111
700MHZ, LOW JITTER
DIFFERENTIAL-TO-3.3V LVPECL FREQUENCY SYNTHESIZER
DIFFERENTIAL CLOCK INPUT INTERFACE
The CLK /nCLK accepts LVDS, LVPECL, LVHSTL, SSTL, HCSL
and other differential signals. Both VSWING and VOH must meet the
VPP and VCMR input requirements. Figures 5A to 5E show interface examples for the HiPerClockS CLK/nCLK input driven by
the most common driver types. The input interfaces suggested
here are examples only. Please consult with the vendor of the
driver component to confirm the driver termination requirements.
For example in Figure 5A, the input termination applies for ICS
HiPerClockS LVHSTL drivers. If you are using an LVHSTL driver
from another vendor, use their termination recommendation.
3.3V
3.3V
3.3V
1.8V
Zo = 50 Ohm
CLK
Zo = 50 Ohm
CLK
Zo = 50 Ohm
nCLK
Zo = 50 Ohm
LVPECL
nCLK
HiPerClockS
Input
LVHSTL
ICS
HiPerClockS
LVHSTL Driver
R1
50
R1
50
HiPerClockS
Input
R2
50
R2
50
R3
50
FIGURE 5A. HIPERCLOCKS CLK/NCLK INPUT DRIVEN
ICS HIPERCLOCKS LVHSTL DRIVER
FIGURE 5B. HIPERCLOCKS CLK/NCLK INPUT DRIVEN
3.3V LVPECL DRIVER
BY
3.3V
3.3V
3.3V
3.3V
3.3V
R3
125
BY
R4
125
Zo = 50 Ohm
LVDS_Driv er
Zo = 50 Ohm
CLK
CLK
R1
100
Zo = 50 Ohm
nCLK
LVPECL
R1
84
HiPerClockS
Input
nCLK
Receiv er
Zo = 50 Ohm
R2
84
FIGURE 5C. HIPERCLOCKS CLK/NCLK INPUT DRIVEN
3.3V LVPECL DRIVER
FIGURE 5D. HIPERCLOCKS CLK/NCLK INPUT DRIVEN
3.3V LVDS DRIVER
BY
BY
3.3V
3.3V
3.3V
LVPECL
Zo = 50 Ohm
C1
Zo = 50 Ohm
C2
R3
125
R4
125
CLK
nCLK
R5
100 - 200
R6
100 - 200
R1
84
HiPerClockS
Input
R2
84
R5,R6 locate near the driver pin.
FIGURE 5E. HIPERCLOCKS CLK/NCLK INPUT DRIVEN
3.3V LVPECL DRIVER WITH AC COUPLE
8430DY-111
BY
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11
REV. F JUNE 1, 2005
PRELIMINARY
Integrated
Circuit
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ICS8430-111
700MHZ, LOW JITTER
DIFFERENTIAL-TO-3.3V LVPECL FREQUENCY SYNTHESIZER
POWER CONSIDERATIONS
This section provides information on power dissipation and junction temperature for the ICS8430-111.
Equations and example calculations are also provided.
1. Power Dissipation.
The total power dissipation for the ICS8430-111 is the sum of the core power plus the power dissipated in the load(s).
The following is the power dissipation for VCC = 3.3V + 5% = 3.465V, which gives worst case results.
NOTE: Please refer to Section 3 for details on calculating power dissipated in the load.
•
•
Power (core)MAX = VCC_MAX * IEE_MAX = 3.465V * 120mA = 415.8mW
Power (outputs)MAX = 30mW/Loaded Output pair
If all outputs are loaded, the total power is 2 * 30mW = 60mW
Total Power_MAX (3.465V, with all outputs switching) = 415.8mW + 60mW = 475.8mW
2. Junction Temperature.
Junction temperature, Tj, is the temperature at the junction of the bond wire and bond pad and directly affects the reliability of the
device. The maximum recommended junction temperature for HiPerClockSTM devices is 125°C.
The equation for Tj is as follows: Tj = θJA * Pd_total + TA
Tj = Junction Temperature
θJA = Junction-to-Ambient Thermal Resistance
Pd_total = Total Device Power Dissipation (example calculation is in section 1 above)
TA = Ambient Temperature
In order to calculate junction temperature, the appropriate junction-to-ambient thermal resistance θJA must be used. Assuming a
moderate air flow of 200 linear feet per minute and a multi-layer board, the appropriate value is 42.1°C/W per Table 7 below.
Therefore, Tj for an ambient temperature of 70°C with all outputs switching is:
70°C + 0.476W * 42.1°C/W = 90°C. This is well below the limit of 125°C.
This calculation is only an example. Tj will obviously vary depending on the number of loaded outputs, supply voltage, air flow,
and the type of board (single layer or multi-layer).
TABLE 7. THERMAL RESISTANCE θJA
FOR
32-PIN LQFP, FORCED CONVECTION
θJA by Velocity (Linear Feet per Minute)
Single-Layer PCB, JEDEC Standard Test Boards
Multi-Layer PCB, JEDEC Standard Test Boards
0
200
500
67.8°C/W
47.9°C/W
55.9°C/W
42.1°C/W
50.1°C/W
39.4°C/W
NOTE: Most modern PCB designs use multi-layered boards. The data in the second row pertains to most designs.
8430DY-111
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REV. F JUNE 1, 2005
PRELIMINARY
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ICS8430-111
700MHZ, LOW JITTER
DIFFERENTIAL-TO-3.3V LVPECL FREQUENCY SYNTHESIZER
3. Calculations and Equations.
The purpose of this section is to derive the power dissipated into the load.
LVPECL output driver circuit and termination are shown in Figure 6.
VCCO
Q1
VOUT
RL
50
VCCO - 2V
FIGURE 6. LVPECL DRIVER CIRCUIT
AND
TERMINATION
To calculate worst case power dissipation into the load, use the following equations which assume a 50Ω load, and a termination
voltage of V - 2V.
CCO
•
For logic high, VOUT = V
OH_MAX
(V
CCO_MAX
•
-V
OH_MAX
=V
OL_MAX
CCO_MAX
-V
OL_MAX
CCO_MAX
– 0.9V
) = 0.9V
For logic low, VOUT = V
(V
=V
CCO_MAX
– 1.7V
) = 1.7V
Pd_H is power dissipation when the output drives high.
Pd_L is the power dissipation when the output drives low.
Pd_H = [(V
OH_MAX
– (V
CCO_MAX
- 2V))/R ] * (V
CCO_MAX
L
-V
OH_MAX
) = [(2V - (V
CCO_MAX
))/R ] * (V
-V
OH_MAX
CCO_MAX
L
-V
)=
OH_MAX
[(2V - 0.9V)/50Ω) * 0.9V = 19.8mW
Pd_L = [(V
OL_MAX
– (V
CCO_MAX
- 2V))/R ] * (V
L
CCO_MAX
-V
OL_MAX
) = [(2V - (V
CCO_MAX
-V
OL_MAX
))/R ] * (V
L
CCO_MAX
-V
OL_MAX
)=
[(2V - 1.7V)/50Ω) * 1.7V = 10.2mW
Total Power Dissipation per output pair = Pd_H + Pd_L = 30mW
8430DY-111
www.icst.com/products/hiperclocks.html
13
REV. F JUNE 1, 2005
PRELIMINARY
Integrated
Circuit
Systems, Inc.
ICS8430-111
700MHZ, LOW JITTER
DIFFERENTIAL-TO-3.3V LVPECL FREQUENCY SYNTHESIZER
RELIABILITY INFORMATION
TABLE 8. θJAVS. AIR FLOW TABLE
FOR
32 LEAD LQFP
θJA by Velocity (Linear Feet per Minute)
Single-Layer PCB, JEDEC Standard Test Boards
Multi-Layer PCB, JEDEC Standard Test Boards
0
200
500
67.8°C/W
47.9°C/W
55.9°C/W
42.1°C/W
50.1°C/W
39.4°C/W
NOTE: Most modern PCB designs use multi-layered boards. The data in the second row pertains to most designs.
TRANSISTOR COUNT
The transistor count for ICS8430-111 is: 3960
8430DY-111
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REV. F JUNE 1, 2005
PRELIMINARY
Integrated
Circuit
Systems, Inc.
PACKAGE OUTLINE - Y SUFFIX
FOR
ICS8430-111
700MHZ, LOW JITTER
DIFFERENTIAL-TO-3.3V LVPECL FREQUENCY SYNTHESIZER
32 LEAD LQFP
TABLE 9. PACKAGE DIMENSIONS
JEDEC VARIATION
ALL DIMENSIONS IN MILLIMETERS
BBA
SYMBOL
MINIMUM
NOMINAL
MAXIMUM
32
N
1.60
A
A1
0.05
A2
1.35
1.40
0.15
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
0.80 BASIC
e
L
0.45
q
0°
0.60
0.75
7°
0.10
ccc
Reference Document: JEDEC Publication 95, MS-026
8430DY-111
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REV. F JUNE 1, 2005
PRELIMINARY
Integrated
Circuit
Systems, Inc.
ICS8430-111
700MHZ, LOW JITTER
DIFFERENTIAL-TO-3.3V LVPECL FREQUENCY SYNTHESIZER
TABLE 10. ORDERING INFORMATION
Part/Order Number
Marking
Package
Shipping Packaging
Temperature
ICS8430DY-111
ICS8430DY-111
32 Lead LQFP
tray
0°C to 70°C
ICS8430DY-111T
ICS8430DY-111
32 Lead LQFP
1000 tape & reel
0°C to 70°C
The aforementioned trademark, HiPerClockS™ is a trademark of Integrated Circuit Systems, Inc. or its subsidiaries in the United States and/or other countries.
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.
8430DY-111
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REV. F JUNE 1, 2005