IS43/46DR86400B, IS43/46DR16320B

Integrated Silicon Solution, Inc. – www.issi.com –

7

Rev. I, 8/01/2012

DLL Enable/Disable

The DLL must be enabled for normal operation. DLL enable is required during power up initialization, and upon returning to normal

operation after having the DLL disabled. The DLL is automatically disabled when entering self refresh operation and is automatically

re-enabled upon exit of self refresh operation. Any time the DLL is enabled (and subsequently reset), 200 clock cycles must occur

before a Read command can be issued to allow time for the internal clock to be synchronized with the external clock. Failing to wait

for synchronization to occur may result in a violation of the tAC or tDQSCK parameters.

Extended Mode Register 1(EMR[1]) Diagram

A12

0

1

BA1

0

BA0

1

0

0

RDQS/DM RDQS#

DQS

DQS#

1

0

0

DM

Hi-Z

DQS

DQS#

A10

0

1

DM

Hi-Z

DQS

Hi-Z

0

1

0

RDQS

RDQS#

DQS

DQS#

1

1

1

RDQS

Hi-Z

DQS

Hi-Z

A9

A8

A7

0

0

0

0

0

1

0

1

0

1

0

0

1

1

1

A5

A4

A3

0

0

0

A6

A2

0

0

1

0

0

0

1

0

0

1

0

1

1

1

0

1

0

0

1

1

1

0

1

1

1

0

1

1

1

A1

A0

0

0

1

1

Qoff

Output buffer enabled

Ouput buffer disabled

RDQS Enable

A11

(RDQS)

A10

(DQS#)

Strobe Function Matrix

Disable

A12

Qoff

Enable

DQS#

A11

RDQS

Enable

Disable

A10

DQS#

OCD Calibration Program

A9

OCD

Program

OCD Calibration mode exit; maintain setting

Drive(1)

A8

Drive(0)

A7

A6

Rtt

Additive Latency

0

Rtt(NOMINAL)

A5

Additive

Latency

1

ODT Disabled

2

75 ohms

A4

3

150 ohms

4

50 ohms

A3

5

Reserved

Rtt

Reserved

A1

D.I.C

Output Drive Impedance Control

Address

Field

Mode

Register

DLL enable

A0

DLL

Normal Strength (100%)

Enable

Reduced strength (60%)

Disable

A2

Notes:

1.

A13 is reserved for future use and must be set to 0 when programming the EMR[1].

2.

If RDQS is enabled, the DM function is disabled. RDQS is active for reads and don’t care for writes. The x16 option does not support RDQS. This must be set to 0

when programming the EMR[1] for the x16 option.

3.

When Adjust mode is issued, AL from previously set value must be applied.

4.

After setting to default, OCD calibration mode needs to be exited by setting A9-A7 to 000.