ICS ICS95V847

ICS95V847
Integrated
Circuit
Systems, Inc.
2.5V Wide Range Frequency Clock Driver (45MHz - 233MHz)
Recommended Application:
• Zero Delay Board Fan Out, SO-DIMM
• Provides complete DDR registered DIMM solution
with ICSSSTV16857, ICSSSTV16859 or
ICSSSTV32852
GND
CLKC0
CLKT0
GND
VDD
CLK_INT
CLK_INC
AVDD
AGND
CLKC1
CLKT1
VDD
Product Description/Features:
• Low skew, low jitter PLL clock driver
• 1 to 5 differential clock distribution (SSTL_2)
• Feedback pins for input to output synchronization
• Spread Spectrum tolerant inputs
Switching Characteristics:
• CYCLE - CYCLE jitter: <60ps
• OUTPUT - OUTPUT skew: <60ps
• Period jitter: ±30ps
• DUTY CYCLE: 49.5% - 50.5%
1
2
3
4
5
6
7
8
9
10
11
12
ICS95V847
Pin Configuration
24
23
22
21
20
19
18
17
16
15
14
13
CLKT4
CLKC4
CLKC3
CLKT3
VDD
FB_INT
FB_INC
FB_OUTC
FB_OUTT
CLKT2
CLKC2
GND
24-Pin TSSOP
4.40 mm. Body, 0.65 mm. pitch
Functionality
Block Diagram
INPUTS
OUTPUTS
PLL State
AVDD CLK_INT
FB_OUTT
FB_OUTC
CLK_INC CLKT CLKC FB_OUTT FB_OUTC
GND
L
H
L
H
L
H
Bypassed/off
GND
H
L
H
L
H
L
Bypassed/off
2.5V
(nom)
L
H
L
H
L
H
on
2.5V
(nom)
H
L
H
L
H
L
on
FB_INT
FB_INC
CLK_INC
CLK_INT
CLKT0
CLKC0
PLL
CLKT1
CLKC1
CLKT2
CLKC2
CLKT3
CLKC3
CLKT4
CLKC4
0718D—04/08/05
ICS95V847
Pin Descriptions
PIN NUMBER
PIN NAME
TYPE
DESCRIPTION
5, 12, 20
VDD
PWR
Power supply, 2.5V
1, 4, 13
GND
PWR
Ground
8
AVDD
PWR
Analog power supply, 2.5V
9
AGND
PWR
A n a l o g gr o u n d
3, 11, 15, 21, 24
CLKT[0:4]
OUT
"Tr ue" Clock of differential pair outputs
2, 10, 14, 22, 23
CLKC[0:4]
OUT
"Complementar y" clocks of differential pair outputs
6
CLK_INT
IN
"True" reference clock input
7
CLK_INC
IN
"Complementar y" reference clock input
16
FB_OUTT
OUT
"True" " Feedback output, dedicated for external feedback. It switches
at the same frequency as the CLK. This output must be wired to
FB_INT
17
FB_OUTC
OUT
"Complementar y" Feedback output, dedicated for external feedback. It
switches at the same frequency as the CLK. This output must be wired
to FB_INC
19
FB_INT
IN
"True" Feedback input, provides feedback signal to the internal PLL for
synchronization with CLK_INT to eliminate phase error
18
FB_INC
IN
"Complementar y" Feedback input, provides signal to the internal PLL
for synchronization with CLK_INC to eliminate phase error
This PLL Clock Buffer is designed for a VDD of 2.5V, an AVDD of 2.5V and differential data input and output levels.
ICS95V847 is a zero delay buffer that distributes a differential clock input pair (CLK_INT, CLK_INC) to five differential
pair of clock outputs (CLKT[4:0], CLKC[4:0]) and one differential pair feedback clock output (FB_OUT, FB_OUTC). The
clock outputs are controlled by input clock (CLK_INT, CLK_INC), the feedback clock (FB_INT, FB_INC) and the analog
power input (AVDD). When AVDD is grounded, the PLL is turned off and bypassed for test purposes.
The PLL in ICS95V847 clock driver uses the input clock (CLK_INC, CLK_INT) and the feedback clock (FB_INT,
FB_INC) to provide high-performance, low-skew, low-jitter differential output clocks (CLKT[4:0], CLKC[4:0]). ICS95V847
is also able to track Spread Spectrum Clock (SSC) for reduced EMI.
ICS95V847 is characterized for operation from 0°C to 85°C.
0718D—04/08/05
2
ICS95V847
Absolute Maximum Ratings
Supply Voltage (VDD & AVDD) . . . . . . . . . . .
Logic Inputs . . . . . . . . . . . . . . . . . . . . . . . . .
Ambient Operating Temperature . . . . . . . . . .
Storage Temperature . . . . . . . . . . . . . . . . . . .
-0.5V to 4.6V
GND - 0.5V to VDD + 0.5V
0°C to +85°C
-65°C to +150°C
Stresses above 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 other conditions above those
listed in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions
for extended periods may affect product reliability.
Electrical Characteristics - Input/Supply/Common Output Parameters
TA = 0 - 85°C; Supply Voltage AVDD, VDD = 2.5 V +/- 0.2V (unless otherwise stated)
PARAMETER
Input High Current
Input Low Current
Operating Supply
Current
High Impedance
Output Current
Input Clamp Voltage
SYMBOL
I IH
I IL
IDD2.5
IDDPD
IOZ
VIK
High-level output
voltage
VOH
Low-level output voltage
VOL
CONDITIONS
VI = V DD or GND
VI = VDD or GND
CL = 0pf @ 200MHz
CL = 0pf
VDD = 2.7V, Vout = VDD or
GND
VDD = 2.3V Iin = -18mA
IOH = -1 mA
IOH = -12 mA
IOL =1 mA
IOH =12 mA
VI = GND or V DD
MIN
5
TYP
MAX
5
148
100
UNITS
µA
µA
mA
µA
±10
mA
-1.2
V
V
V
V
V
pF
VDD - 0.1
1.7V
CIN
Input Capacitance1
1
Guaranteed by design at 233MHz, not 100% tested in production.
0718D—04/08/05
3
2.5
0.1
0.6
3.5
ICS95V847
Recommended Operating Condition (see note1)
TA = 0 - 85°C; Supply Voltage AVDD, VDD = 2.5 V +/- 0.2V (unless otherwise stated)
PARAMETER
Supply Voltage
SYMBOL
VDD, A VDD
VDD + 0.6
UNITS
V
V
V
V
V
-0.3
VDD + 0.3
V
0.36
0.7
VDD + 0.6
VDD + 0.6
V
V
V OX
VDD/2 - 0.15
V DD/2 + 0.15
V
VIX
VDD/2 - 0.2
V DD/2 + 0.2
V
IOH
-6.4
mA
Low level output current
IOL
5.5
mA
Operating free-air
temperature
TA
85
°C
Low level input voltage
VIL
High level input voltage
VIH
DC input signal voltage
(note 2)
Differential input signal
voltage (note 3)
Output differential crossvoltage (note 4)
Input differential crossvoltage (note 4)
High level output
current
CONDITIONS
CLKT, CLKC, FB_INC
PD#
CLKT, CLKC, FB_INC
PD#
VIN
VID
DC - CLKT, FB_INT
AC - CLKT, FB_INT
MIN
2.3
-0.3
V DD/2 + 0.18
1.7
0
Notes:
1. Unused inputs must be held high or low to prevent them from floating.
2. DC input signal voltage specifies the allowable DC execution of differential input.
3. Differential inputs signal voltages specifies the differential voltage [VTR-VCP]
required for switching, where VT is the true input level and VCP is the
complementary input level.
4. Differential cross-point voltage is expected to track variations of VDD and is the
voltage at which the differential signal must be crossing.
0718D—04/08/05
4
TYP
2.5
0.4
MAX
2.7
VDD/2 - 0.18
0.7
2.1
V DD/2
ICS95V847
Timing Requirements
TA = 0 - 85°C; Supply Voltage AVDD, VDD = 2.5 V +/- 0.2V (unless otherwise stated)
CONDITIONS
PARAMETER
SYMBOL
MIN
MAX
Max clock frequency
Application Frequency
Range
Input clock duty cycle
CLK stabilization
2.5V+0.2V @ 25oC
freqop
freqApp
2.5V+0.2V @ 25oC
dtin
UNITS
45
233
MHz
95
210
MHz
40
60
%
15
µs
TSTAB
Switching Characteristics (see note 3)
PARAMETER
Low-to high level
propagation delay time
High-to low level propagation
delay time
Output enable time
Output disable time
Period jitter
Half-period jitter
Input clock slew rate
Output clock slew rate
Cycle to Cycle Jitter1
Phase error
Output to Output Skew
SYMBOL
CONDITION
MIN
TYP
MAX
UNITS
tPLH1
CLK_IN to any output
5.5
ns
tPLL1
CLK_IN to any output
5.5
ns
tEN
tdis
PD# to any output
PD# to any output
100MHz to 200MHz
100MHz to 200MHz
5
5
ns
ns
ps
ps
V/ns
V/ns
ps
ps
ps
Tjit (per)
t(jit_hper)
t sl(i)
t sl(o)
Tcyc -Tcyc
t(phase error)
Tskew
-30
-75
1
1
100MHz to 200MHz
4
-50
Notes:
1. Refers to transition on noninverting output in PLL bypass mode.
2. While the pulse skew is almost constant over frequency, the duty cycle error
increases at higher frequencies. This is due to the formula: duty cycle=twH/tc, where
the cycle (tc) decreases as the frequency goes up.
3. Switching characteristics guaranteed for application frequency range.
4. Static phase offset shifted by design.
0718D—04/08/05
5
0
30
30
4
2.5
60
50
60
ICS95V847
Parameter Measurement Information
VDD
V(CLKC)
R = 60Ω
R = 60Ω VDD/2
V(CLKC)
ICS95V847
GND
Figure 1. IBIS Model Output Load
VDD/2
C = 14 pF -VDD/2
ICS95V847
R = 10Ω
Z = 60Ω
SCOPE
Z = 50Ω
R = 50Ω
V(TT)
R = 10Ω
Z = 60Ω
Z = 50Ω
R = 50Ω
V(TT)
C = 14 pF
-VDD/2
-VDD/2
NOTE: V(TT) = GND
Figure 2. Output Load Test Circuit
YX, FBOUTC
YX, FBOUTT
tc(n)
tc(n+1)
tjit(cc) = tc(n) ± tc(n+1)
Figure 3. Cycle-to-Cycle Jitter
0718D—04/08/05
6
ICS95V847
Parameter Measurement Information
CLK_INC
CLK_INT
FB_INC
FB_INT
t( ) n
n=N
t( ) n
1
t( )=
N
(N is a large number of samples)
Figure 4. Static Phase Offset
YX #
YX
YX, FB_OUTC
YX, FB_OUTT
t(SK_O)
Figure 5. Output Skew
YX, FB_OUTC
YX, FB_OUTT
YX, FB_OUTC
YX, FB_OUTT
1
fO
t(jit_per) = tC(n) - 1
fO
Figure 6. Period Jitter
0718D—04/08/05
7
t ( ) n+1
ICS95V847
Parameter Measurement Information
YX, FB_OUTC
YX, FB_OUTT
t (hper_n+1)
t (hper_n)
1
fo
t(jit_Hper) = t(jit_Hper_n) - 1
2xfO
Figure 7. Half-Period Jitter
80%
80%
VID , VOD
Clock Inputs
and Outputs
20%
20%
Rise tsl
Fall tsl
Figure 8. Input and Output Slew Rates
0718D—04/08/05
8
ICS95V847
c
N
L
E1
INDEX
AREA
E
1 2
α
D
A
A2
A1
-Ce
In Millimeters
In Inches
SYMBOL COMMON DIMENSIONS COMMON DIMENSIONS
MIN
MAX
MIN
MAX
A
-1.20
-.047
A1
0.05
0.15
.002
.006
A2
0.80
1.05
.032
.041
b
0.19
0.30
.007
.012
c
0.09
0.20
.0035
.008
SEE VARIATIONS
SEE VARIATIONS
D
6.40 BASIC
0.252 BASIC
E
E1
4.30
4.50
.169
.177
0.65 BASIC
0.0256 BASIC
e
L
0.45
0.75
.018
.030
SEE VARIATIONS
SEE VARIATIONS
N
a
0°
8°
0°
8°
aaa
-0.10
-.004
VARIATIONS
N
SEATING
PLANE
b
aaa C
24
D mm.
MIN
7.70
D (inch)
MAX
7.90
MIN
.303
Reference Doc.: JEDEC Publication 95, MO-153
10-0035
4.40 mm. Body, 0.65 mm. pitch TSSOP
(0.0256 Inch)
(173 mil)
Ordering Information
ICS95V847yGLF-T
Example:
ICS XXXX y G LF- T
Designation for tape and reel packaging
Annealed Lead Free (Optional)
Package Type
G = TSSOP
Revision Designator (will not correlate with datasheet revision)
Device Type
Prefix
ICS = Standard Device
0718D—04/08/05
9
MAX
.311