DATASHEET
551S SEPTEMBER 20, 2018 1 ©2018 Integrated Device Technology, Inc.
Low Skew 1 to 4 Clock Buffer 551S
Description
The 551S is a low cost, high-speed single inp ut to four outp ut
clock buffer. The 551S has best in class Additive Phase Jitter
of sub 50fsec.
IDT makes many non-PLL and PLL based low skew output
devices as well as Zero Delay Buffers to synchronize clocks.
Contact IDT for all of your clocking needs.
Features
Low additive phase jitter RMS: 50fs
Extremely low skew outputs (50ps)
Low cost clock buffer
Packaged in 8-pin SOIC and 8-pin DFN, Pb-free
Input/Output clock frequency up to 200MHz
Non-inverting output clock
Ideal for network i ng clock s
Operating Volta ge s: 1.8V to 3.3V
Output Enable mode tri-states ou tputs
Advanced, low power CMOS process
Extended temperature range (-40°C to +105°C)
Block Diagram
Q1
ICLK
Q2
Q3
Q4
Output Enable
LOW SKEW 1 TO 4 CLOCK BUFFER 2 SEPTEMBER 20, 2018
551S DATASHEET
Pin Assignment
Pin Descriptions
External Componen ts
A minimum number of external components are required for proper operation. A decoupling capacitor of 0.01F should be
connected between VDD o n pin 7 a nd GND o n pi n 6, as close to th e d evice as possible . A 33 series terminating resistor may
be used on each clock output if the trace is longer than 1 inch.
1
2
3
ICLK
4
Q1
Q2
VDD
Q3
GND
Q4
8
7
6
5
OE
8 Pin (150 mil) SOIC
1
2
3
ICLK
4
Q1
Q2
VDD
Q3
GND
Q4
8
7
6
5
OE
8-pin DFN
Pin
Number
Pin
Name
Pin
Type
Pin Description
1 ICLK Input Clock input. Internal pull-up resistor.
2 Q1 Output Clock output 1.
3 Q2 Output Clock output 2.
4 Q3 Output Clock output 3.
5 Q4 Output Clock output 4.
6 GND Power Connect to ground.
7 VDD Power Connect +1.8V, +2.5V or +3.3V.
8 OE Input Output Enable. Tri-states outputs when low. Internal pull-up resistor.