DDR4 ² Memory Subsystem

PLL

Command

Address

Clock

Clock

Data

CAB4A

Data

CPU / DSP / Ethernet MCU

MEMORY

CONTROLLER

(MCH)

CAB4A

www.ti.com

SNAS630B – JULY 2013 – REVISED OCTOBER 2013

CAB4A - DDR4 Register

32-Bit 1:2 Command/Address/Control Buffer and 1:4 Differential Clock Buffer

Check for Samples: CAB4A

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FEATURES

DESCRIPTION

The CAB4 is 32-bit 1:2 Command/Address/Control

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•

DDR4RCD01 JEDEC Compliant

Buffer and 1:4 differential Clock Buffer designed for

•

DDR4 RDIMM and LRDIMM up to DDR4-2400

operation on DDR4 registered DIMMs with a 1.2 V

•

32 Bits 1-to-2 Register Outputs

VDD mode.

•

1-to-4 Differential Clock Buffer

All inputs are pseudo-differential using external or

•

1.2V Operation

internal voltage reference. All outputs are full swing

CMOS drivers optimized to drive 15 to 50

Ω effective

•

PLL with Internal Feedback

terminated traces in DDR4 RDIMM, LRDIMM and 3D-

•

Configurable Driver Strength

Stacked DIMM applications. The clock outputs,

•

Scalable Weak Driver

command/address outputs, control outputs, data

buffer control outputs can be enabled in groups, and

•

Programmable Latency

independently

driven

with

different

strengths

to

•

Output Driver Calibration

compensate for different DIMM net topologies. The

•

Address Mirroring and Inversion

DDR4 Register operates from a differential clock

(CK_t and CK_c). Inputs are registered at the

•

DDR4 Full-Parity Operation

crossing of CK_t going HIGH, and CK_c going LOW.

•

The input signals could be either re-driven to the

•

CA Bus Training Mode

outputs if one of the input signals DCS[n:0]_n is

driven LOW or it could be used to access device

•

internal control registers when certain input conditions

•

Up to 16-Logical Ranks Support for 3DS

are met.

RDIMMs and LRDIMMs

The

device

is

characterized

in

the

operating

•

Up to 4 Physical Ranks Support for RDIMMs

temperature range from -40°C to 95°C.

and LRDIMMs

Figure 1. DDR4 - RDIMM Memory Subsystem

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PRODUCTION DATA information is current as of publication date.

Copyright © 2013, Texas Instruments Incorporated

Products conform to specifications per the terms of the Texas

Instruments standard warranty. Production processing does not

necessarily include testing of all parameters.