CDCU2A877 Series

1.8-V phase-lock loop clock driver with high output drive for DDR2 SDRAM applications

Link to Manufacturer Page: https://www.ti.com/

Catalog

1.8-V phase-lock loop clock driver with high output drive for DDR2 SDRAM applications

Part	Ratio - Input:Output [custom]	Ratio - Input:Output [custom]	Input	Supplier Device Package	Supplier Device Package [y]	Supplier Device Package [x]	Operating Temperature [Max]	Voltage - Supply [Min]	Voltage - Supply [Max]	Mounting Type	Output	Number of Circuits	Frequency - Max [Max]
Texas Instruments CDCU2A877NMKT	1	10	Clock	52-NFBGA	4.5	7	70 °C	1.7 V	1.9 V	Surface Mount	Clock	1	410 MHz
Texas Instruments CDCU2A877NMKR	2	11	Clock	52-NFBGA	4.5	7	70 °C	1.7 V	1.9 V	Surface Mount	Clock	1	410 MHz
Texas Instruments CDCU2A877ZQLT	1	10	SSTL-18	52-BGA MICROSTAR JUNIOR (7x4.5)			70 ░C	1.7 V	1.9 V	Surface Mount	SSTL-18	1	410 MHz
Texas Instruments CDCU2A877ZQLR	1	10	SSTL-18	52-BGA MICROSTAR JUNIOR (7x4.5)			70 ░C	1.7 V	1.9 V	Surface Mount	SSTL-18	1	410 MHz

Key Features

• 1.8-V/1.9-V Phase Lock Loop Clock Driver for Double Data Rate ( DDR II ) ApplicationsSpread Spectrum Clock CompatibleOperating Frequency: 125 MHz to 410 MHzApplication Frequency: 160 MHz to 410 MHzLow Jitter (Cycle-Cycle): ±40 psLow Output Skew: 35 psStabilization Time <6 µsDistributes One Differential Clock Input to 10 Differential OutputsHigh-Drive Version of CDCUA87752-Ball mBGA (MicroStar Junior™; BGA, 0,65-mm pitch)External Feedback Pins ( FBIN,FBIN) are Used to Synchronize the Outputs to the Input ClocksMeets or Exceeds CUA877/CUA878 Specification PLL Standard for PC2-3200/4300/5300/6400Fail-Safe InputsMicroStar Junior is a trademark of Texas Instruments.1.8-V/1.9-V Phase Lock Loop Clock Driver for Double Data Rate ( DDR II ) ApplicationsSpread Spectrum Clock CompatibleOperating Frequency: 125 MHz to 410 MHzApplication Frequency: 160 MHz to 410 MHzLow Jitter (Cycle-Cycle): ±40 psLow Output Skew: 35 psStabilization Time <6 µsDistributes One Differential Clock Input to 10 Differential OutputsHigh-Drive Version of CDCUA87752-Ball mBGA (MicroStar Junior™; BGA, 0,65-mm pitch)External Feedback Pins ( FBIN,FBIN) are Used to Synchronize the Outputs to the Input ClocksMeets or Exceeds CUA877/CUA878 Specification PLL Standard for PC2-3200/4300/5300/6400Fail-Safe InputsMicroStar Junior is a trademark of Texas Instruments.

Description

The CDCU2A877 is a high-performance, low-jitter, low-skew, zero-delay buffer that distributes a differential clock input pair (CK,CK) to 10 differential pairs of clock outputs (Yn,Yn) and to one differential pair of feedback clock outputs (FBOUT,FBOUT). The clock outputs are controlled by the input clocks (CK,CK), the feedback clocks (FBIN,FBIN), the LVCMOS control pins (OE, OS), and the analog power input (AVDD). When OE is low, the clock outputs, except FBOUT/FBOUT, are disabled while the internal PLL continues to maintain its locked-in frequency. OS (output select) is a program pin that must be tied to GND or VDD. When OS is high, OE functions as previously described. When OS and OE are both low, OE has no affect on Y7/Y7, they are free running. When AVDDis grounded, the PLL is turned off and bypassed for test purposes. When both clock inputs (CK,CK) are logic low, the device enters in a low power mode. An input logic detection circuit on the differential inputs, independent from input buffers, detects the logic low level and performs in a low power state where all outputs, the feedback, and the PLL are off. When the clock inputs transition from being logic low to being differential signals, the PLL turns back on, the inputs and the outputs are enabled, and the PLL obtains phase lock between the feedback clock pair (FBIN,FBIN) and the clock input pair (CK,CK) within the specified stabilization time. The CDCU2A877 is able to track spread spectrum clocking (SSC) for reduced EMI. This device operates from 0°C to 70°C. The CDCU2A877 is a high-performance, low-jitter, low-skew, zero-delay buffer that distributes a differential clock input pair (CK,CK) to 10 differential pairs of clock outputs (Yn,Yn) and to one differential pair of feedback clock outputs (FBOUT,FBOUT). The clock outputs are controlled by the input clocks (CK,CK), the feedback clocks (FBIN,FBIN), the LVCMOS control pins (OE, OS), and the analog power input (AVDD). When OE is low, the clock outputs, except FBOUT/FBOUT, are disabled while the internal PLL continues to maintain its locked-in frequency. OS (output select) is a program pin that must be tied to GND or VDD. When OS is high, OE functions as previously described. When OS and OE are both low, OE has no affect on Y7/Y7, they are free running. When AVDDis grounded, the PLL is turned off and bypassed for test purposes. When both clock inputs (CK,CK) are logic low, the device enters in a low power mode. An input logic detection circuit on the differential inputs, independent from input buffers, detects the logic low level and performs in a low power state where all outputs, the feedback, and the PLL are off. When the clock inputs transition from being logic low to being differential signals, the PLL turns back on, the inputs and the outputs are enabled, and the PLL obtains phase lock between the feedback clock pair (FBIN,FBIN) and the clock input pair (CK,CK) within the specified stabilization time. The CDCU2A877 is able to track spread spectrum clocking (SSC) for reduced EMI. This device operates from 0°C to 70°C.