H5GQ1H24AFR-R0C datasheet(61/173 Pages) HYNIX

61 / 173 page

This document is a general product description and is subject to change without notice. Hynix Semiconductor does not assume any

responsability for use of circuits described. No patent licenses are implied.

Rev. 1.0 /Nov. 2009

H5GQ1H24AFR

Data Preamble

When enabled by bit A5, non‐gapless READ bursts will be preceded by a fixed data preamble on the DQ

and DBI# pins of 4 U.I. duration. The programmed READ latency does not change when the Data

Preamble is enabled. The pattern is not encoded with RDBI, however, if RDBI is disabled, the DBI# pins

will not toggle and drive a HIGH.

Temperature Sensor

The on‐chip temperature sensor is enabled by bit A6.

A detailed description of the Temperature Sensor can be found in the VENDOR ID, TEMP SENSOR and

SCAN section.

Half VREFD

This mode allows users to adjust the Vref level in case the GDDR5 SGRAM is operated without

termination: when bit A7 is set to’1’, a Vref level of nominally 0.5 * VDDQ is expected at the VREFD pin or

being generated internally (see Figure 31).

Duty Cycle Correction (DCC)

Bits A10 and A11 control the operation of the duty cycle corrector (DCC). The DCC can be used to cancel

out a static duty cycle error on the WCK clocks. For more details see Duty Cycle Correction (DCC) in the

section entitled OPERATION.

VREFD Selection Options Summary

The following table summarizes the complete set of VREFD selection options.

Table 15 VREFD Selection Options

MR6

MR7

Description

Internal VREFD

Half VREFD

External

Internal 0.7 * VDDQ

Internal 0.5 * VDDQ

H5GQ1H24AFR-R0C Datasheet(PDF) 61 Page - Hynix Semiconductor