FAN6550 Ver la hoja de datos (PDF) - Fairchild Semiconductor

Número de pieza

componentes Descripción

Fabricante

FAN6550

2A DDR Bus Termination Regulator

Fairchild Semiconductor 

PRODUCT SPECIFICATION

FAN6550

Applications

Using the FAN6550 for DDR Bus Termination

The circuit schematic in Figure 1 shows a recommended

approach for constructing a bus terminating solution for a

DDR bus. This circuit can be used in PC memory and Graph-

ics memory applications as shown in Figures 2 and 3. Note

that the FAN6550 can provide the voltage reference (VREF)

and terminating voltages (VTT). Using the layout

as shown in Figures 4, 5, and 6, and measuring the VTT

performance using the test setup as described in Figure 7,

the FAN6550 delivered a VTT ± 20mV for 1A to 2A loads

(see Figure 8). Table 1 provides a recommended parts list.

Bus Termination Solutions for Others Buses

Table 2 provides a summary of various bus termination VREF

& VTT requirements. The FAN6550 can be used for those

applications.

168/184/208-PIN DIMM CONNECTORS

AND SDRAM/SGRAM MODULES

TERMINATION

RESISTORS

PC CHIP SET

NORTHBRIDGE

DATA LINE, CLOCK LINES,

ADDRESS LINES, CONTROL LINES

TERMINATION

RESISTORS

VTT

VREF

Figure 2. Complete Termination Solution PC Main Memory (PC Motherboard)

FAN6550

REV. 1.0.2 3/11/02

5

Share Link: