PCK9446 Datasheet, PDF (1/17 Pages) NXP Semiconductors – 2.5 V and 3.3 V LVCMOS clock fan-out buffer

PCK9446
2.5 V and 3.3 V LVCMOS clock fan-out buffer
Rev. 01 — 10 April 2006
Product data sheet
1. General description
The PCK9446 is a 2.5 V and 3.3 V compatible 1 : 10 clock distribution buffer designed for
low-voltage mid-range to high-performance telecom, networking and computing
applications. Both 3.3 V, 2.5 V and dual supply voltages are supported for mixed-voltage
applications. The PCK9446 offers 10 low skew outputs and 2 selectable inputs for clock
redundancy. The outputs are configurable and support 1 : 1 and 1 : 2 output to input
frequency ratios. The PCK9446 is specified for the extended temperature range of
−40 °C to +85 °C.
The PCK9446 is a full static design supporting clock frequencies up to 250 MHz. The
signals are generated and retimed on-chip to ensure minimal skew between the three
output banks. Two independent LVCMOS compatible clock inputs are available. This
feature supports redundant clock sources or the addition of a test clock into the system
design. Each of the three output banks can be individually supplied by 2.5 V or 3.3 V
supporting mixed voltage applications. The FSELx pins choose between division of the
input reference frequency by one or two. The frequency divider can be set individually for
each of the three output banks. The PCK9446 can be reset and the outputs are disabled
by deasserting the MR/OE pin (logic HIGH state). Asserting OE will enable the outputs.
All inputs accept LVCMOS signals while the outputs provide LVCMOS compatible levels
with the capability to drive terminated 50 Ω transmission lines. Please refer to the
PCK9456 specification for a 1 : 10 mixed voltage buffer with LVPECL compatible inputs.
For series terminated transmission lines, each of the PCK9446 outputs can drive one or
two traces giving the devices an effective fan-out of 1 : 20. The device is packaged in a
32-lead LQFP package which has a 7 mm × 7 mm body size with a conservative 0.8 mm
pin spacing.
2. Features
I Configurable 10 outputs LVCMOS clock distribution buffer
I Compatible to single, dual and mixed 3.3 V/2.5 V voltage supply
I Wide range output clock frequency up to 250 MHz
I Designed for mid-range to high-performance telecom, networking and computer
applications
I Supports applications requiring clock redundancy
I Maximum output skew of 200 ps (100 ps within one bank)
I Selectable output configurations per output bank
I 3-stateable outputs
I 32-lead LQFP packaging
I Ambient operating temperature range of −40 °C to +85 °C