83905AM http://www.icst.com/products/hiperclocks.html REV. A JANUARY 20, 2005
1
Integrated
Circuit
Systems, Inc.
ICS83905
LOW SKEW, 1:6 CRYSTAL INTERFACE-TO-
LVCMOS / LVTTL FANOUT BUFFER
PRELIMINARY
GENERAL DESCRIPTION
The ICS83905 is a low skew, 1-to-6 LVCMOS /
LVTTL Fanout Buffer and a member of the
HiPerClockS™ family of High Performance Clock
Solutions from ICS. The ICS83905 single ended
clock input accepts LVCMOS or LVTTL input lev-
els. The low impedance LVCMOS/LVTTL outputs are designed
to drive 50Ω series or parallel terminated transmission lines.
The effective fanout can be increased from 6 to 12 by utilizing
the ability of the outputs to drive two series terminated lines.
The ICS83905 is characterized at full 3.3V, 2.5V, and 1.8V,
mixed 3.3V/2.5V, 3.3V/1.8V and 2.5V/1.8V output operating
supply mode. Guaranteed output and part-to-part skew char-
acteristics along with the 1.8V output capabilities makes the
ICS83905 ideal for high performance, single ended applica-
tions that also require a limited output voltage.
BLOCK DIAGRAM PIN ASSIGNMENT
FEATURES
•6 LVCMOS / LVTTL outputs
•Crystal oscillator interface
•Output frequency range: 10MHz to 50MHz
•Crystal input frequency range: 10MHz to 50MHz
•Output skew: 10ps (typical)
•5V tolerant enable inputs
•Synchronous output enables
•Operating supply modes: Full 3.3V, 2.5V and 1.8V,
mixed 3.3Vcore/2.5V or1.8V operating supply, and
mixed 2.5V core/1.8V operating supply
•0°C to 70°C ambient operating temperature
•Lead-Free package fully RoHS compliant
•Pin compatible to MPC905
•Industrial version available upon request
HiPerClockS™
ICS
ICS83905
16-Lead SOIC
3.9mm x 9.9mm x 1.38mm body package
M Pacakge
Top View
ICS83905
16-Lead TSSOP
4.4mm x 3.0mm x 0.92mm body package
G Pacakge
Top View
SYNCHRONIZE
SYNCHRONIZE
BCLK0
BCLK1
BCLK2
BCLK3
BCLK4
BCLK5
ENABLE 1
ENABLE 2
XTAL_IN
XTAL_OUT
XTAL_OUT
ENABLE 2
GND
BCLK0
VDDo
BCLK1
GND
BCLK2
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
XTAL_IN
ENABLE 1
BCLK5
VDDO
BCLK4
GND
BCLK3
VDD
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.
20 19 18 17 16
6 7 8 9 10
1
2
3
4
5
15
14
13
12
11
ENABLE2
XTAL_OUT
XTAL_IN
ENABLE1
nc
BCLK5
VDDO
BCLK4
GND
GND
GND
GND
BCLK0
VDDO
BCLK1
GND
GND
BCLK2
VDD
BCLK3
ICS83905
20-Lead VFQFN
4mm x 4mm x 0.9mm
body package
K Package
Top View