IDT ICS8732-01 Maximum output frequency Datasheet

ICS8732-01
LOW VOLTAGE, LOW SKEW
3.3V LVPECL CLOCK GENERATOR
GENERAL DESCRIPTION
Features
The ICS8732-01 is a low voltage, low skew,
3.3V LVPECL Clock Generator. The ICS8732-01 has two
selectable clock inputs. The CLK0, nCLK0 pair can accept
most standard differential input levels. The single ended
clock input accepts LVCMOS or LVTTL input levels. The
ICS8732-01 has a fully integrated PLL along with frequency
configurable outputs. An external feedbackinput and
outputs regenerate clocks with “zero delay”.
• Ten differential 3.3V LVPECL outputs
• Selectable differential CLK0, nCLK0 or
LVCMOS/LVTTL CLK1 inputs
• CLK0, nCLK0 supports the following input types:
LVPECL, LVDS, LVHSTL, SSTL, HCSL
• CLK1 accepts the following input levels:
LVCMOS or LVTTL
• Maximum output frequency: 350MHz
The ICS8732-01 has multiple divide select pins for each
bank of outputs along with 3 independent feedback divide
select pins allowing the ICS8732-01 to function both as a
frequency multiplier and divider. The PLL_SEL input can
be usedto bypass the PLL for test and system debug
purposes.In bypass mode, the input clock is routed around
the PLLand into the internal output dividers.
• VCO range: 250MHz to 700MHz
• External feedback for “zero delay” clock regeneration
with configurable frequencies
• Cycle-to-cycle jitter: CLK0, nCLK0, 50ps (maximum)
CLK1, 80ps (maximum)
• Output skew: 150ps (maximum)
• Static phase offset: -150ps to 150ps
• Lead-Free package fully RoHS compliant
VCCO
QFB1
nQFB1
QFB0
nQFB0
VEE
VCC
FB_IN
2
38
nQB3
nQA1
5
35
QB2
VEE
6
34
VEE
PLL_SEL
7
33
MR
QA3
nQA3
ICS8732-01
QB1
nQB1
VCCO
QB2
nQB2
nQA2
10
30
QB1
QA3
11
29
nQB0
nQA3
12
VCCO
31
VEE
DIV_SELA1
QFB0
nQFB0
28
13
27
14 15 16 17 18 19 20 21 22 23 24 25 26
QFB1
nQFB1
QB0
VEE
DIV_SELB0
VCC
QB3
nQB3
FBDIV_SEL2
52-Lead LQFP
10mm x 10mm x 1.4mm package body
Y package
Top View
MR
8732AY-01
nFB_IN
VCCO
QA0
QA2
nQA2
QB0
nQB0
FBDIV_SEL0
52 51 50 49 48 47 46 45 44 43 42 41 40
39
nc
DIV_SELB1
FBDIV_SEL1
1
VCCA
DIV_SELB1
FBDIV_SEL0
VCCO
QA1
nQA1
CLK_SEL
DIV_SELB0
÷4 ÷6 ÷8 ÷10
÷8 ÷12 ÷16 ÷20
QA0
nQA0
CLK0
DIV_SELA1
÷2 ÷4 ÷6 ÷8
÷2 ÷4 ÷8 ÷12
nCLK0
DIV_SELA0
1
CLK1
PLL_SEL
0
PLL
VEE
FB_IN
nFB_IN
1
VCC
CLK1
0
DIV_SELA0
CLK0
nCLK0
VEE
CLK_SEL
FBDIV_SEL1
PIN ASSIGNMENT
FBDIV_SEL2
BLOCK DIAGRAM
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REV. E MAY 2, 2013
ICS8732-01
LOW VOLTAGE, LOW SKEW
3.3V LVPECL CLOCK GENERATOR
TABLE 1. PIN DESCRIPTIONS
Number
1, 8, 32,
39, 40
2, 3,
4, 5
6,
13, 17,
27, 34,
45, 52
Name
Type
Description
VCCO
Power
Output supply pins.
QA0, nQA0,
QA1, nQA1
Output
Differential output pair. LVPECL interface levels.
VEE
Power
Negative supply pins.
7
PLL_SEL
Input
9, 10,
11, 12
QA2, nQA2,
QA3, nQA3
Output
14
DIV_SELA1
Input
15
DIV_SELA0
Input
VCC
Power
16, 26,
46
18
CLK1
Input
19
nCLK0
Input
20
CLK0
Input
21
CLK_SEL
Input
22
VCCA
Power
23
nc
Unused
24
DIV_SELB1
Input
25
DIV_SELB0
Input
28, 29,
30, 31
QB0, nQB0,
QB1, nQB1
Output
33
MR
Input
35, 36,
37, 38
41, 42,
43, 44
QB2, nQB2,
QB3, nQB3
QFB1, nQFB1,
QFB0, nQFB0
47
FB_IN
Input
48
nFB_IN
Input
49
FBDIV_SEL0
Input
50
FBDIV_SEL1
Input
51
FBDIV_SEL2
Input
Pullup
Selects between the PLL and reference clock as the input to the dividers.
When LOW, selects reference clock. When HIGH, selects PLL.
LVCMOS / LVTTL interface levels.
Differential output pairs. LVPECL interface levels.
Determines output divider valued in Table 3.
LVCMOS / LVTTL interface levels.
Determines output divider valued in Table 3.
Pulldown
LVCMOS / LVTTL interface levels.
Pulldown
Core supply pins.
Pulldown LVCMOS / LVTTL reference clock input.
Pullup
Inver ting differential clock input.
Pulldown Non-inver ting differential clock input.
Clock select input. When LOW, selects CLK0, nCLK0.
Pulldown
When HIGH, selects CLK1. LVCMOS / LVTTL interface levels.
Analog supply pin.
No connect.
Determines output divider valued in Table 3.
Pulldown
LVCMOS / LVTTL interface levels.
Determines output divider valued in Table 3.
Pulldown
LVCMOS / LVTTL interface levels.
Differential output pairs. LVPECL interface levels.
Active High Master Reset. When logic HIGH, the internal dividers
are reset causing the true outputs Qx to go low and the inver ted outputs
Pulldown
nQx to go high. When LOW, the internal dividers and the outputs are
enabled. LVCMOS / LVTTL interface levels.
Output
Differential output pairs. LVPECL interface levels.
Output
Differential feedback output pairs. LVPECL interface levels.
Feedback input to phase detector for regenerating clocks
with "zero delay".
Feedback input to phase detector for regenerating clocks
Pullup
with "zero delay".
Selects divide value for differential feedback output pairs.
Pulldown
LVCMOS / LVTTL interface levels.
Selects divide value for differential feedback output pairs.
Pulldown
LVCMOS / LVTTL interface levels.
Selects divide value for differential feedback output pairs.
Pulldown
LVCMOS / LVTTL interface levels.
Pulldown
NOTE: Pullup and Pulldown refer to internal input resistors. See Table 2, Pin Characteristics, for typical values.
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REV. E MAY 2, 2013
ICS8732-01
LOW VOLTAGE, LOW SKEW
3.3V LVPECL CLOCK GENERATOR
TABLE 2. PIN CHARACTERISTICS
Symbol
Parameter
CIN
Input Capacitance
Test Conditions
4
pF
RPULLUP
Input Pullup Resistor
51
kΩ
RPULLDOWN
Input Pulldown Resistor
51
kΩ
TABLE 3A. CONTROL INPUT FUNCTION TABLE
FOR
Typical
Maximum
Units
QA0:QA3 OUTPUTS
Inputs
Outputs
MR
PLL_SEL
DIV_SELA1
DIV_SELA0
1
X
X
X
Low
0
1
0
0
fVCO/2
QA0:QA3, nQA0:nQA3
0
1
0
1
fVCO/4
0
1
1
0
fVCO/6
0
1
1
1
fVCO/8
0
0
0
0
fREF_CLK/2
0
0
0
1
fREF_CLK/4
0
0
1
0
fREF_CLK/6
0
0
1
1
fREF_CLK/8
TABLE 3B. CONTROL INPUT FUNCTION TABLE
FOR
QB0:QB3 OUTPUTS
Inputs
Outputs
MR
PLL_SEL
DIV_SELB1
DIV_SELB0
1
X
X
X
Low
0
1
0
0
fVCO/2
QB0:QB3, nQB0:nQB3
0
1
0
1
fVCO/4
0
1
1
0
fVCO/8
0
1
1
1
fVCO/12
0
0
0
0
fREF_CLK/2
0
0
0
1
fREF_CLK/4
0
0
1
0
fREF_CLK/8
0
0
1
1
fREF_CLK/12
8732AY-01
Minimum
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REV. E MAY 2, 2013
ICS8732-01
LOW VOLTAGE, LOW SKEW
3.3V LVPECL CLOCK GENERATOR
TABLE 3C. CONTROL INPUT FUNCTION TABLE
FOR
QFB0, QFB1
Inputs
MR
PLL_SEL
FBDIV_SEL2
FBDIV_SEL1
FBDIV_SEL0
1
X
X
X
X
Outputs
QFB0, QFB1
nQFB0, nQFB1
Low
0
1
0
0
0
fVCO/4
0
1
0
0
1
fVCO/6
0
1
0
1
0
fVCO/8
0
1
0
1
1
fVCO/10
0
1
1
0
0
fVCO/8
0
1
1
0
1
fVCO/12
0
1
1
1
0
fVCO/16
0
1
1
1
1
fVCO/20
0
0
0
0
0
fREF_CLK/4
0
0
0
0
1
fREF_CLK/6
0
0
0
1
0
fREF_CLK/8
0
0
0
1
1
fREF_CLK/10
0
0
1
0
0
fREF_CLK/8
0
0
1
0
1
fREF_CLK/12
0
0
1
1
0
fREF_CLK/16
0
0
1
1
1
fREF_CLK/20
TABLE 4A. QX OUTPUT FREQUENCY W/FB_IN = QFB0
OR
QFB1
Inputs
fVCO
CLK1 (MHz)
FB_IN
FBDIV_SEL2
FBDIV_SEL1
FBDIV_SEL0
Output Divider Mode
QFB
0
0
0
÷4
62.5
Minimum
(NOTE 1)
QFB
0
0
1
÷6
41.67
Maximum
175
(NOTE 2)
116.67
QFB
0
1
0
÷8
31.25
87.5
fREF_CLK x 8
QFB
0
1
1
÷10
25
70
fREF_CLK x 10
QFB
1
0
0
÷8
31.25
87.5
fREF_CLK x 8
QFB
1
0
1
÷12
20.83
58.33
fREF_CLK x 12
QFB
1
1
0
÷16
15.62
43.75
fREF_CLK x 16
35
fREF_CLK x 20
QFB
1
1
1
12.5
÷20
NOTE 1: VCO frequency range is 250MHz to 700MHz.
NOTE 2: The maximum input frequency that the phase detector can accept is 175MHz.
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4
fREF_CLK x 4
fREF_CLK x 6
REV. E MAY 2, 2013
ICS8732-01
LOW VOLTAGE, LOW SKEW
3.3V LVPECL CLOCK GENERATOR
ABSOLUTE MAXIMUM RATINGS
Supply Voltage, VCC
4.6V
Inputs, VI
-0.5V to VCC + 0.5 V
Outputs, IO
Continuous Current
Surge Current
50mA
100mA
Package Thermal Impedance, θJA
42.3°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 5A. 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 Voltage
3.135
3.3
3.465
V
VCCA
Analog Supply Voltage
3.135
3.3
3.465
V
VCCO
Output Supply Voltage
3.135
3.3
3.465
V
ICC
Power Supply Current
165
mA
ICCA
Analog Supply Current
15
mA
TABLE 5B. LVCMOS/LVTTL DC CHARACTERISTICS, VCC = VCCA = VCCO = 3.3V±5%, TA = 0°C TO 70°C
Symbol Parameter
VIH
Input High Voltage
VIL
Input Low Voltage
IIH
Input High Current
IIL
Input Low Current
Test Conditions
CLK1
CLK_SEL, PLL_SEL,
DIV_SELAx, DIV_SELBx,
FBDIV_SELx, MR
CLK1
CLK_SEL, PLL_SEL,
DIV_SELAx, DIV_SELBx,
FBDIV_SELx, MR
CLK_SEL, MR, CLK1
DIV_SELAx, DIV_SELBx,
FBDIV_SELx
PLL_SEL
CLK_SEL, MR, CLK1
DIV_SELAx, DIV_SELBx,
FBDIV_SELx
Maximum
Units
2
VCC+ 0.3
V
2
VCC+ 0.3
V
-0.3
1.3
V
-0.3
0.8
V
VCC = VIN = 3.465V
150
µA
VCC = VIN = 3.465V
5
µA
PLL_SEL
8732AY-01
Typical
VCC = 3.465V,
VIN = 0V
-5
µA
VCC = 3.465V,
VIN = 0V
-150
µA
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Minimum
REV. E MAY 2, 2013
ICS8732-01
LOW VOLTAGE, LOW SKEW
3.3V LVPECL CLOCK GENERATOR
TABLE 5C. DIFFERENTIAL DC CHARACTERISTICS, VCC = VCCA = VCCO = 3.3V±5%, TA = 0°C TO 70°C
Symbol
Parameter
Maximum
Units
CLK0, FB_IN
VCC = VIN = 3.465V
Test Conditions
150
µA
nCLK0, nFB_IN
VCC = VIN = 3.465V
5
µA
IIH
Input High Current
IIL
Input Low Current
VPP
Peak-to-Peak Input Voltage
VCMR
Common Mode Input Voltage; NOTE 1, 2
Minimum
Typical
CLK0, FB_IN
VCC = 3.465V, VIN = 0V
-5
µA
nCLK0, nFB_IN
VCC = 3.465V, VIN = 0V
-150
µA
0.15
1.3
V
VEE + 0.5
VCC - 0.85
V
Maximum
Units
NOTE 1: For single ended applications, the maximum input voltage for FB_IN, nFB_IN is VCC + 0.3V.
NOTE 2: Common mode voltage is defined as VIH.
TABLE 5D. 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
Maximum
Units
200
MHz
Maximum
350
Units
MHz
150
ps
150
ps
50
ps
80
ps
10
700
52
ms
ps
%
NOTE 1: Outputs terminated with 50Ω to VCCO - 2V.
TABLE 6. PLL INPUT REFERENCE CHARACTERISTICS, VCC = VCCA = VCCO = 3.3V±5%, TA = 0°C TO 70°C
Symbol
Parameter
fREF
Input Reference Frequency
Test Conditions
Minimum
Typical
TABLE 7. AC CHARACTERISTICS, VCC = VCCA = VCCO = 3.3V±5%, TA = 0°C TO 70°C
Symbol
fMAX
Parameter
Output Frequency
t(Ø)
Static Phase Offset; NOTE 1
tsk(o)
Output Skew; NOTE 2, 3, 4
CLK0,
Cycle-to-Cycle Jitter ; nCLK
NOTE 3
CLK1
tjit(cc)
Test Conditions
Minimum
PLL_SEL = 3.3V,
fREF = 100MHz, fVCO = 400MHz
-150
Typical
tL
PLL Lock Time
Output Rise/Fall Time
20% to 80%
200
tR / tF
odc
Output Duty Cycle
fOUT ≤ 175MHz
48
All parameters measured at fMAX unless noted otherwise.
NOTE 1: Defined as the time difference between the input reference clock and the averaged feedback input
when the PLL is locked and the input reference frequency is stable.
NOTE 2: Defined as skew between outputs at the same supply voltage and with equal load conditions.
Measured at the output differential cross points.
NOTE 3: This parameter is defined in accordance with JEDEC Standard 65.
NOTE 4: All outputs in divide by 4 configuration.
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REV. E MAY 2, 2013
ICS8732-01
LOW VOLTAGE, LOW SKEW
3.3V LVPECL CLOCK GENERATOR
PARAMETER MEASUREMENT INFORMATION
2V
V CC ,
VCCA,
VCCO
Qx
Vcc
SCOPE
nCLK0,
nFB_IN
LVPECL
V
CLK0,
FB_IN
nQx
V
Cross Points
PP
CMR
VEE
VEE
-1.3V ± 0.165V
3.3V OUTPUT LOAD AC TEST CIRCUIT
DIFFERENTIAL INPUT LEVEL
nQA0:nQA3,
nQB0:nQB3,
nQFB0,
nQFB1
Qx
QA0:QA3,
QB0:QB3,
QFB0, QFB1
➤
nQy
tcycle
n
➤
nQx
➤
tcycle n+1
➤
t jit(cc) = tcycle n –tcycle n+1
Qy
1000 Cycles
tsk(o)
CYCLE-TO-CYCLE JITTER
OUTPUT SKEW
nCLK0
VOH
CLK0,
CLK1
VOL
nFB_IN
VOH
FB_IN
80%
80%
VSW I N G
Clock
Outputs
20%
20%
tR
tF
VOL
➤
➤ t(Ø)
OUTPUT RISE/FALL TIME
STATIC PHASE OFFSET
nQA:nQA3,
nQFB0, nQFB1
QA:QA3,
QFB0, QFB1
t PW
t
odc =
PERIOD
t PW
x 100%
t PERIOD
OUTPUT DUTY CYCLE/PULSE WIDTH/PERIOD
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REV. E MAY 2, 2013
ICS8732-01
LOW VOLTAGE, LOW SKEW
3.3V LVPECL CLOCK GENERATOR
APPLICATION INFORMATION
WIRING THE DIFFERENTIAL INPUT TO ACCEPT SINGLE ENDED LEVELS
Figure 1 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
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.
VCC
R1
1K
Single Ended Clock Input
CLK
V_REF
nCLK
C1
0.1u
R2
1K
FIGURE 1. SINGLE ENDED SIGNAL DRIVING DIFFERENTIAL INPUT
TERMINATION
FOR
LVPECL OUTPUTS
drive 50Ω transmission lines. Matched impedance techniques
should be used to maximize operating frequency and minimize
signal distortion. Figures 2A and 2B 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
125Ω
FIN
Zo = 50Ω
Zo = 50Ω
FOUT
50Ω
RTT =
1
Z
((VOH + VOL) / (VCC – 2)) – 2 o
Zo = 50Ω
VCC - 2V
RTT
84Ω
FIGURE 2A. LVPECL OUTPUT TERMINATION
8732AY-01
FIN
50Ω
84Ω
FIGURE 2B. LVPECL OUTPUT TERMINATION
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REV. E MAY 2, 2013
ICS8732-01
LOW VOLTAGE, LOW SKEW
3.3V LVPECL CLOCK GENERATOR
POWER SUPPLY FILTERING TECHNIQUES
As in any high speed analog circuitry, the power supply pins
are vulnerable to random noise. The ICS8732-01 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 3 illustrates how a 10Ω
resistor along with a 10μF and a .01μF bypass capacitor
should be connected to each VCCA pin.
3.3V
VCC
.01μF
10Ω
VCCA
.01μF
10μF
FIGURE 3. POWER SUPPLY FILTERING
DIFFERENTIAL CLOCK INPUT INTERFACE
component to confirm the driver termination requirements. For
example in Figure 4A, the input termination applies for LVHSTL
drivers. If you are using an LVHSTL driver from another
vendor, use their termination recommendation.
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 4A to 4D show
interface examples for the 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
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 4A. CLK/NCLK INPUT DRIVEN BY
LVHSTL DRIVER
FIGURE 4B. CLK/NCLK INPUT DRIVEN BY
3.3V LVPECL DRIVER
3.3V
3.3V
3.3V
3.3V
3.3V
R3
125
R4
125
Zo = 50 Ohm
LVDS_Driv er
Zo = 50 Ohm
CLK
CLK
R1
100
Zo = 50 Ohm
nCLK
LVPECL
R1
84
HiPerClockS
Input
Receiv er
R2
84
FIGURE 4C. CLK/NCLK INPUT DRIVEN BY
3.3V LVPECL DRIVER
8732AY-01
nCLK
Zo = 50 Ohm
FIGURE 4D. CLK/NCLK INPUT DRIVEN BY
3.3V LVDS DRIVER
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REV. E MAY 2, 2013
ICS8732-01
LOW VOLTAGE, LOW SKEW
3.3V LVPECL CLOCK GENERATOR
LAYOUT GUIDELINE
Figure 5 shows a schematic example of the ICS8732-01. In this
example, the CLK0/nCLK0 input is selected. The decoupling ca-
pacitors should be physically located near the power pin. For
ICS8732-01, the unused outputs can be left floating.
Zo = 50
+
VCC
R14
1K
Zo = 50
-
VCC
VCC
R4
50
10
C16
10uF
C11
0.1uF
DIV_SELA1
DIV_SELA0
VCC
Zo = 50
Zo = 50
R1
50
R2
50
DIV_SELA1
DIV_SELA0
VCC
VEE
CLK1
nCLK0
CLK0
CLK_SEL
VCCA
nc
DIV_SELB1
DIV_SELB0
VCC
52
51
50
49
48
47
46
45
44
43
42
41
40
VEE
FBDIV_SEL2
FBDIV_SEL1
FBDIV_SEL0
nFB_IN
FB_IN
VCC
VEE
nQFB0
QFB0
nQFB1
QFB1
VCCO
FBDIV_SEL2
FBDIV_SEL1
FBDIV_SEL0
R10
50
R13
1K
R11
50
R12
50
27
28
29
30
31
32
33
34
35
36
37
38
39
R3
50
R6
50
VEE
QB0
nQB0
QB1
nQB1
VCCO
MR
VEE
QB2
nQB2
QB3
nQB3
VCCO
DIV_SELB1
DIV_SELB0
LVPECL
14
15
16
17
18
19
20
21
22
23
24
25
26
R5
50
U1
ICS8732-01
VEE
nQA3
QA3
nQA2
QA2
VCCO
PLL_SEL
VEE
nQA1
QA1
nQA0
QA0
VCCO
R7
13
12
11
10
9
8
7
6
5
4
3
2
1
VCCA
Zo = 50
Logic Input Pin Examples
VCC
Set Logic
Input to
'1'
RU1
1K
VCC
Set Logic
Input to
'0'
RU2
SP
To Logic
Input
pins
RD1
SP
+
To Logic
Input
pins
RD2
1K
Zo = 50
-
VCC=3.3V
SP = Spare (i.e. not intstalled)
(U1-1)
VCC
C1
0.1uF
(U1-8)
C2
0.1uF
(U1-16)
R8
50
(U1-26)
C3
0.1uF
C4
0.1uF
(U1-32)
(U1-39)
C5
0.1uF
(U1-40)
C6
0.1uF
R7
50
(U1-46)
C7
0.1uF
C8
0.1uF
R9
50
Bypass capacitors located near the power pins
FIGURE 5. ICS8732-01 LVPECL BUFFER SCHEMATIC EXAMPLE
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POWER CONSIDERATIONS
This section provides information on power dissipation and junction temperature for the ICS8732-01.
Equations and example calculations are also provided.
1. Power Dissipation.
The total power dissipation for the ICS8732-01 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 * 165mA = 572mW
Power (outputs)MAX = 30mW/Loaded Output pair
If all outputs are loaded, the total power is 10 * 30mW = 300mW
Total Power_MAX (3.465V, with all outputs switching) = 572mW + 300mW = 872mW
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 the 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 36.4°C/W per Table 8 below.
Therefore, Tj for an ambient temperature of 70°C with all outputs switching is:
70°C + 0.872W * 36.4°C/W = 101.7°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 8. THERMAL RESISTANCE θJA FOR 52-PIN LQFP, FORCED CONVECTION
θJA by Velocity (Linear Feet per Minute)
0
Single-Layer PCB, JEDEC Standard Test Boards
Multi-Layer PCB, JEDEC Standard Test Boards
58.0°C/W
42.3°C/W
200
500
47.1°C/W
36.4°C/W
42.0°C/W
34.0°C/W
NOTE: Most modern PCB designs use multi-layered boards. The data in the second row pertains to most designs.
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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
OL_MAX
CCO_MAX
-V
OL_MAX
CCO_MAX
– 0.9V
) = 0.9V
For logic low, VOUT = V
(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
-V
OH_MAX
))/R ] * (V
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
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RELIABILITY INFORMATION
TABLE 9.
θJAVS. AIR FLOW TABLE FOR 52 LEAD LQFP
θJA by Velocity (Linear Feet per Minute)
0
Single-Layer PCB, JEDEC Standard Test Boards
Multi-Layer PCB, JEDEC Standard Test Boards
58.0°C/W
42.3°C/W
200
500
47.1°C/W
36.4°C/W
42.0°C/W
34.0°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 ICS8732-01 is: 4916
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PACKAGE OUTLINE - Y SUFFIX
FOR
52 LEAD LQFP
TABLE 10. PACKAGE DIMENSIONS
JEDEC VARIATION
ALL DIMENSIONS IN MILLIMETERS
SYMBOL
BCC
MINIMUM
NOMINAL
MAXIMUM
52
N
A
--
--
1.60
A1
0.05
--
0.15
A2
1.35
1.40
1.45
b
0.22
0.32
0.38
c
0.09
--
0.20
D
12.00 BASIC
D1
10.00 BASIC
E
12.00 BASIC
E1
10.00 BASIC
0.65 BASIC
e
L
0.45
--
0.75
θ
0°
--
7°
ccc
--
--
0.08
Reference Document: JEDEC Publication 95, MS-026
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ICS8732-01
LOW VOLTAGE, LOW SKEW
3.3V LVPECL CLOCK GENERATOR
TABLE 11. ORDERING INFORMATION
Part/Order Number
8732AY-01LF
8732AY-01LFT
Marking
ICS8732AY-01LF
ICS8732AY-01LF
Package
52 lead "Lead Free" LQFP
52 lead "Lead Free" LQFP
Shipping Packaging
Tube
500 Tape and Reel
Temperature
0°C to +70°C
0°C to +70°C
NOTE: "LF" suffix to the part number are the PB-free configuration, RoHS compliant
While the information presented herein has been checked for both accuracy and reliability, Integrated Device Technology, Inc. (IDT) 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 and industrial
applications. Any other applications such as those requiring high reliability, or other extraordinary environmental requirements are not recommended without additional processing by IDT. IDT reserves
the right to change any circuitry or specifications without notice. IDT does not authorize or warrant any IDT product for use in life support devices or critical medical instruments.
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ICS8732-01
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REVISION HISTORY SHEET
Rev
Table
Page
1
T2
3
Pin Characteristics Table - changed CIN from max. 4pF to typical 4pF.
T4A
4
Qx Output Frequency Table - changed the CLK1 min. column to correlate with
the VCO change.
B
C
C
C
C
8
Added Differential Clock Input Interface in the Application Information section.
Power Supply DC Characteristics Table - changed IEE from 240mA max. to
165mA max., and ICCA from 14mA max. to 15mA max.
Power Considerations - recalculated Power Dissipation and Junction
Temperatures to correspond with Table 5A.
Updated LVPECL Output Termination diagrams.
Added Schematic Layout.
Block Diagram - changed REF_SEL to CLK_SEL.
Ordering Information Table - corrected Tape & Reel Count to read 500 from
1000.
Qx Output Frequency Table - changed NOTE 2 from "200MHz" to "175MHz".
Features Section - added Lead Free bullet.
Ordering Information Table - added Lead Free par t number and note.
Power Supply DC Characteristics Table - corrected IEE to read ICC.
LVPECL DC Characteristics Table -corrected VOH max. from VCCO - 1.0V to
VCCO - 0.9V.
Power Considerations - corrected power dissipation to reflect VOH max in Table
T11
8
10
1
15
T4A
T11
T5A
T5D
D
4
1
15
5
6
11 - 12
E
T11
E
T 5D
8732AY-01
Absolute Maximum Ratings - changed VO to IO and included Continuous
Current and Surge Current
5
C
C
5
T5A
C
Description of Change
Features Section - changed VCO min. from 200MHz to 250MHz.
15
17
9
5D.
Updated datasheet's header/footer with IDT from ICS.
Removed ICS prefix from Par t/Order Number column.
Added Contact Page.
VOH Maximum = VCCO - 0.9
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16
Date
5/20/03
6/23/03
9/24/03
3/3/04
4/29/04
10/19/04
5/23/05
5/31/05
4/13/07
7/31/10
5/2/13
REV. E MAY 2, 2013
ICS8732-01
LOW VOLTAGE, LOW SKEW
3.3V LVPECL CLOCK GENERATOR
We’ve Got Your Timing Solution.
6024 Silver Creek Valley Road
San Jose, CA 95138
Sales
Tech Support
800-345-7015 (inside USA)
+408-284-8200 (outside USA)
Fax: 408-284-2775
[email protected]
© 2010 Integrated Device Technology, Inc. All rights reserved. Product specifications subject to change without notice. IDT, the IDT logo, ICS and HiPerClockS are trademarks of Integrated Device Technology, Inc.
Accelerated Thinking is a service mark of Integrated Device Technology, Inc. All other brands, product names and marks are or may be trademarks or registered trademarks used to identify products or services of
their respective owners.
Printed in USA
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