Philips Semiconductors

Product specification

PCK2509SL

50–150 MHz 1:9 SDRAM clock driver

2

2000 Dec 01

853–2230 25137

FEATURES

PC100/PC133 SDRAM applications

clock signal is present.

locked when outputs are disabled.

bank of four outputs

outputs to the clock input

DESCRIPTION

The PCK2509SL is a high-performance, low-skew, low-jitter,

phase-locked 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

is input compatible with both 2.5 V and 3.3 V input voltage ranges. It

also provides integrated series-damping resistors that make it ideal

for driving point-to-point loads.

One bank of five outputs and one bank of four outputs provide nine

low-skew, low-jitter copies of CLK. Output signal duty cycles are

adjusted to 50 percent, independent of the duty cycle at CLK. Each

bank of outputs can be enabled or disabled separately via the

control (1G and 2G) inputs. When the G inputs are high, the outputs

switch in phase and frequency with CLK; when the G inputs are low,

the outputs are disabled to the logic–low state.

Unlike many products containing PLLs, the PCK2509SL 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 PCK2509SL 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, and

following any changes to the PLL reference or feedback signals. The

The PCK2509SL is characterized for operation from 0

°C to +70 °C.

PIN CONFIGURATION

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

AGND

CLK

2Y0

1Y0

2Y1

GND

1Y1

GND

2Y3

1Y2

2Y2

GND

FBIN

GND

1Y3

1Y4

1G

FBOUT

SW00389

2G

ORDERING INFORMATION

PACKAGES

TEMPERATURE RANGE

ORDER CODE

DRAWING NUMBER

24-Pin Plastic TSSOP

0 to +70

°C

PCK2509SLDH

SOT355-1