CSP2510D

Features:

• Phase-Lock Loop Clock Distribution for Synchronous DRAM Applications
• Distributes one clock input to one bank of ten outputs
• Output enable bank control
• External feedback (FBIN) pin is used to synchronize the outputs to the clock input signal
• No external RC network required for PLL loop stability
• Operates at 3.3V VDD
• tpd Phase Error at 166MHz: < ±150ps
• Jitter (peak-to-peak) at 166MHz: < ±75ps @ 166MHz
• Spread Spectrum Compatible
• Operating frequency 50MHz to 175MHz
• Available in 24-Pin TSSOP package


Application

• SDRAM Modules
• PC Motherboards
• Workstations


Pinout




Specifications

Symbol	Rating	Max	Unit
VDD	Supply Voltage Range	0.5 to +4.6	V
VI(1)	Input Voltage Range	0.5 to +6.5	V
VO(1,2)	Voltage range applied to any output in the high or low state	0.5 to VDD + 0.5	V
IIK (VI <0)	Input clamp current	50	mA
IOK (VO <0 or VO > VDD)	Terminal Voltage with Respect to GND (inputs VIH 2.5, VIL 2.5)	±50	mA
IO (VO = 0 to VDD)	Continuous Output Current	±50	mA
VDD or GND	Continuous Current	±100	mA
TSTG	Storage Temperature Range	65 to +150	°C
TJ	Junction Temperature	+150	°C

Description

The CSP2510D is a high performance, low-skew, low-jitter, phase-lock loop (PLL) clock driver. It uses a PLL to precisely align, in both frequency and phase, the feedback (FBOUT) output to the clock (CLK) input signal.

It is specifically designed for use with synchronous DRAMs. The CSP2510D operates at 3.3V. One bank of ten outputs provide low-skew, low-jitter copies of CLK. Output signal duty cycles are adjusted to 50 percent, independent of the duty cycle at CLK.

The outputs can be enabled or disabled via the control G input. When the G input is high, the outputs switch in phase and frequency with CLK; when the G input is low, the outputs are disabled to the logic-low state. Unlike many products containing PLLs, the CSP2510D does not require external RC networks. The loop filter for the PLL is included on-chip, minimizing component count, board space, and cost. Because it is based on PLL circuitry, the CSP2510D requires a stabilization time to achieve phase lock of the feedback signal to the reference signal.

This stabilization time is required, following power up and application of a fixed-frequency, fixed-phase signal at CLK, as well as following any changes to the PLL reference or feedback signals. The PLL can be bypassed for the test purposes by strapping AVDD to ground.

The CSP2510D is specified for operation from 0°C to +85°C. This device is also available (on special order) in Industrial temperature range (-40°C to +85°C). See ordering information for details.