HYB25L512160AC Datasheet, PDF (16/50 Pages) Infineon Technologies AG – 512MBit Mobile-RAM

HYB25L512160AC–7.5
512MBit Mobile-RAM
Functional Description
3.2.2.1 Partial Array Self Refresh (PASR)
Partial Array Self Refresh is power-saving feature specific to Mobile-RAMs. With PASR, self refresh may be
restricted to variable portions of the total array. The selection comprises all four banks (default), two banks, one
bank, half a bank, and a quarter of one bank. Data written to the non activated memory sections will get lost after
a period defined by t_REF (cf. Table 13).
3.2.2.2 Temperature Compensated Self Refresh (TCSR) with On-Chip Temperature
Sensor
DRAM devices store data as a electrical charge in tiny capacitors that require a periodic refresh in order to retain
the stored information. This refresh requirement heavily depends on the die temperature: high temperature
corresponds to short refresh period, and low temperature to long refresh period.
The Mobile-RAM is equipped with an on-chip temperature sensor which continuously monitors the current die
temperature and adjusts the refresh period in self refresh mode accordingly. By default the on-chip temperature
sensor is enabled (TCSR = 00, see Figure 6 ); the other three TCSR settings use defined temperature values to
adjust the self refresh period with the on-chip temperature sensor being disabled.
Data Sheet
16
Rev. 1.3, 2004-04
10212003-BSPE-77OL