Pin and Signal Descriptions

Pin Descriptions

Table 5: DDR SDRAM Interface Pin Assignments (Continued)

Pin Name

I/O

Pin

Power

Description

 

 

Type

Rail

 

 

 

 

 

 

M_STARTBURST

O

SSTL

VDD_M

Start Burst

 

 

 

 

88F6281 indication of starting a burst read transaction.

 

 

 

 

Asserted with the first M_CASn cycle of SDRAM access.

 

 

 

 

NOTE: Must be routed on board to the SDRAM, and back to

 

 

 

 

the 88F6281 as M_STARTBURST_IN. For the

 

 

 

 

recommended length calculation for this routing and

 

 

 

 

termination requirements, see the 88F6180, 88F6190,

 

 

 

 

88F6192, and 88F6281 Design Guide.

 

 

 

 

 

M_START

I

SSTL

VDD_M

Start Burst Input

BURST_IN

 

 

 

 

 

 

 

 

 

M_PCAL

I

Calib

 

SDRAM interface P channel output driver calibration. Connect

 

 

 

 

to VSS through a resistor. The resistor value can vary

 

 

 

 

between 30–70 ohm.

 

 

 

 

NOTE: See the 88F6180, 88F6190, 88F6192, and 88F6281

 

 

 

 

Design Guide for the recommended values of the

 

 

 

 

calibration resistors.

 

 

 

 

 

M_NCAL

I

Calib

 

SDRAM interface N channel output driver calibration. Connect

 

 

 

 

to M_VDD through a resistor. The resistor value can vary

 

 

 

 

between 30–70 ohm.

 

 

 

 

NOTE: See the 88F6180, 88F6190, 88F6192, and 88F6281

 

 

 

 

Design Guide for the recommended values of the

 

 

 

 

calibration resistors.

 

 

 

 

 

Copyright © 2008 Marvell

 

Doc. No. MV-S104859-U0 Rev. E

December 2, 2008, Preliminary

Document Classification: Proprietary Information

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Image 25
Marvel Group 88F6281 specifications Mstartburst Sstl Vddm, Mstart Sstl Vddm, Burstin Mpcal, Mncal