Texas Instruments CDC509PWR Datasheet

CDC509
3.3-V PHASE-LOCK LOOP CLOCK DRIVER
SCAS576B – JULY 1996 – REVISED JANUAR Y 1998
1
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
D
Phase-Lock Loop Clock Distribution for Synchronous DRAM Applications
D
Distributes One Clock Input to One Bank of Five and One Bank of Four Outputs
D
Separate Output Enable for Each Output Bank
D
External Feedback (FBIN) Pin Is Used to Synchronize the Outputs to the Clock Input
D
No External RC Network Required
D
Operates at 3.3-V V
CC
D
Packaged in Plastic 24-Pin Thin Shrink Small-Outline Package
description
The CDC509 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 CDC509 operates at 3.3-V VCC and is designed to drive up to five clock loads per output.
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 CDC509 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 CDC509 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 test purposes by strapping AV
CC
to ground.
The CDC509 is characterized for operation from 0°C to 70°C.
FUNCTION TABLE
INPUTS
OUTPUTS
1G 2G CLK
1Y
(0:4)2Y(0:3)
FBOUT
X X L L L L L LHLLH
L HHLHH H LHHLH
H H H H H H
Copyright 1998, Texas Instruments Incorporated
PRODUCTION DATA information is current as of publication date. Products conform to specifications per the terms of Texas Instruments standard warranty. Production processing does not necessarily include testing of all parameters.
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
CLK AV
CC
V
CC
2Y0 2Y1 GND GND 2Y2 2Y3 V
CC
2G FBIN
1 2 3 4 5 6 7 8 9 10 11 12
AGND
V
CC
1Y0 1Y1
1Y2 GND GND
1Y3
1Y4
V
CC
1G
FBOUT
24 23 22 21 20 19 18 17 16 15 14 13
PW PACKAGE
(TOP VIEW)
CDC509
3.3-V PHASE-LOCK LOOP CLOCK DRIVER
SCAS576B – JULY 1996 – REVISED JANUAR Y 1998
2
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
functional block diagram
1Y2
1Y1
1Y0
PLL
FBIN
AV
CC
2G
CLK
1G
2Y2
2Y1
2Y0
2Y3
FBOUT
1Y3
1Y4
11
14
24
13
23
3
4
5
8
9
21
20
17
16
12
AVAILABLE OPTIONS
PACKAGE
T
A
SMALL OUTLINE
(PW)
0°C to 70°C CDC509PWR
CDC509
3.3-V PHASE-LOCK LOOP CLOCK DRIVER
SCAS576B – JULY 1996 – REVISED JANUAR Y 1998
3
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
Terminal Functions
TERMINAL
NAME NO.
TYPE
DESCRIPTION
CLK 24 I
Clock input. CLK provides the clock signal to be distributed by the CDC509 clock driver. CLK is used to provide the reference signal to the integrated PLL that generates the clock output signals. CLK must have a fixed frequency and fixed phase for the PLL to obtain phase lock. Once the circuit is powered up and a valid CLK signal is applied, a stabilization time is required for the PLL to phase lock the feedback signal to its reference signal.
FBIN 13 I
Feedback input. FBIN provides the feedback signal to the internal PLL. FBIN must be hard-wired to FBOUT to complete the PLL. The integrated PLL synchronizes CLK and FBIN so that there is nominally zero phase error between CLK and FBIN.
1G 11 I
Output bank enable. 1G is the output enable for outputs 1Y(0:4). When 1G is low, outputs 1Y(0:4) are disabled to a logic-low state. When 1G is high, all outputs 1Y(0:4) are enabled and switch at the same frequency as CLK.
2G 14 I
Output bank enable. 2G is the output enable for outputs 2Y(0:3). When 2G is low, outputs 2Y(0:3) are disabled to a logic low state. When 2G is high, all outputs 2Y(0:3) are enabled and switch at the same frequency as CLK.
FBOUT 12 O
Feedback output. FBOUT is dedicated for external feedback. It switches at the same frequency as CLK. When externally wired to FBIN, FBOUT completes the feedback loop of the PLL.
1Y(0:4) 3, 4, 5, 8, 9 O
Clock outputs. These outputs provide low-skew copies of CLK. Output bank 1Y(0:4) is enabled via the 1G input. These outputs can be disabled to a logic-low state by deasserting the 1G control input.
2Y(0:3) 16, 17, 20 21 O
Clock outputs. These outputs provide low-skew copies of CLK. Output bank 2Y(0:3) is enabled via the 2G input. These outputs can be disabled to a logic-low state by deasserting the 2G control input.
AV
CC
23 Power
Analog power supply. A VCC provides the power reference for the analog circuitry. In addition, A V
CC
can be used to bypass the PLL for test purposes. When AVCC is strapped to ground, PLL is bypassed and CLK is buffered directly to the device outputs.
AGND 1 Ground Analog ground. AGND provides the ground reference for the analog circuitry.
V
CC
2, 10, 15, 22 Power Power supply
GND 6, 7, 18, 19 Ground Ground
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)
Supply voltage range, V
CC
–0.5 V to 4.6 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Input voltage range, V
I
(see Note 1) –0.5 V to 6.5 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Voltage range applied to any output in the high
or low state, VO (see Notes 1 and 2) –0.5 V to VCC + 0.5 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Input clamp current, I
IK
(V
I
< 0) –50 mA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Output clamp current, I
OK
(V
O
< 0 or VO > VCC) ±50 mA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Continuous output current, I
O
(V
O
= 0 to VCC) ±50 mA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Continuous current through each VCC or GND ±100 mA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Maximum power dissipation at TA = 55°C (in still air) (see Note 3) 0.7 W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Storage temperature range, T
stg
–65°C to 150°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
NOTES: 1. The input and output negative-voltage ratings may be exceeded if the input and output clamp-current ratings are observed.
2. This value is limited to 4.6 V maximum.
3. The maximum package power dissipation is calculated using a junction temperature of 150°C and a board trace length of 750 mils. For more information, refer to the
Package Thermal Considerations
application note in the
ABT Advanced BiCMOS T echnology Data
Book
, literature number SCBD002.
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