Intel® 820E Chipset

R

Figure 73. 5VREF Circuitry

 

 

 

Vcc supply (3.3 V)

 

 

 

 

 

 

 

 

5 V supply

 

 

 

 

 

 

 

 

 

 

 

1 k

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1 µF

 

 

 

 

 

 

 

 

 

 

 

 

 

 

To system

 

 

 

 

 

 

 

 

To system

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Vref

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

sys_des_5Vref_circ

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Table 41. IDE Checklist

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Checklist Items

Recommendations

 

Reason/Effect

 

 

 

 

 

 

 

 

 

 

PDD[15:0], SDD[15:0]

No extra series termination resistors or

 

These signals have integrated series

 

 

 

 

other pull-ups/pull-downs are required.

 

resistors.

 

 

 

 

PDD7/SDD7 doesn’t require a 10 k

 

NOTE: Simulation data indicates that the

 

 

 

 

pull-down resistor.

 

 

 

 

 

 

 

 

 

integrated series termination resistors are

 

 

 

 

Refer to the ATA TAPI-4 specification.

 

a nominal 33 , but can range from 31

 

 

 

 

 

to 43 .

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

PDIOW#, PDIOR#,

No extra series termination resistors.

 

These signals have integrated series

 

 

 

PDDACK#, PDA[2:0],

Pads for series resistors can be

 

resistors.

 

 

 

PDCS1#, PDCS3#,

implemented if the system designer has

 

NOTE: Simulation data indicates that the

 

 

 

SDIOW#, SDIOR#,

signal integrity concerns.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

integrated series termination resistors are

 

 

 

SDDACK#, SDA[2:0],

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

a nominal 33 , but can range from 31

 

 

 

SDCS1#, SDCS3#

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

to 43 .

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

PDREQ

No extra series termination resistors

 

These signals have integrated series

 

 

 

SDREQ

No pull-down resistors are needed.

 

resistors in the ICH2.

 

 

 

 

These signals have integrated pull-down

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

resistors in the ICH2.

 

 

 

 

 

 

 

 

 

 

PIORDY

No extra series termination resistors.

 

These signals have integrated series

 

 

 

SIORDY

Pull-up to 3.3 V via a 4.7 k

resistor.

 

resistors in the ICH2.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

IRQ14, IRQ15

Recommend 8.2 kto 10 k

pull-up

 

Open-drain outputs from drive

 

 

 

 

resistor to 3.3 V.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

No extra series termination resistors

 

 

 

 

 

 

 

 

 

 

 

 

IDERST#

The PCIRST# signal should be buffered

 

 

 

 

 

 

to form the IDERST# signal. A 33

 

 

 

 

 

 

series termination resistor is

 

 

 

 

 

 

 

 

 

 

 

 

 

 

recommended on this signal.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

132

Design Guide

Page 132
Image 132
Intel 820E manual IDE Checklist