1245

INNOVATIVE
IM1245Y-100
128K X 8 NO POWER SRAM
FEATURES
PIN NAMES
Functional Description
The IM 1245Y–100 is a 1,048,576 bit, fully static NP RAM organized as 128K X 8 using CMOS and an This ‘NO POWER’ RAM has all the normal characteristics of a CMOS static RAM with an impor- tant benefit of data being retained in the absence of power. Data retention current is so small that a minia- ture lithium cell contained within the package providesan energy source to preserve data. Protection againstdata loss has also been incorporated to maintain dataintegrity during power on/off conditions.
The IM 1245Y–100 RAM can be directly used in placeof existing static RAMs. There is no limit to the numberof write cycles that can be executed and no additionalsupport circuitry is required for interface to a micropro-cessor.
INNOVATIVE MICROTECHNOLOGY INC.Phone/Fax-440-322-8083.Website:www.innovativemicrotechnology.com INNOVATIVE
IM1245Y-100
128K X 8 NO POWER SRAM
READ MODE
Maximum Ratings
The IM 1245Y-100 performs a read cycle when- ever WE high and CE low. The unique address speci-fied by the 17 address inputs A0-A16 defines which of the 131,072 bytes of data is to be accessed. Valid data will be available to the eight data output drivers withinaccess time t And Time………………….260oC for 10 sec provided that CE and OE access times are satisfied. If OE or CE access times are not satisfied, data accesswill be measured from the limiting parameter (t or t ), Input Voltage………………-0.5V to 7.0V rather than address. The state of the eight data I/O Input/ Output Voltage…….-0.5V to Vcc + 0.3V lines is controlled by the OE and CE control signals.
The data lines may be in an indeterminate state be- WRITE MODE
Recommended D.C. Operating Conditions
The IM 1245Y-100 is in the write mode whenever CEand WE inputs are held low. The latter occurring falling edge of either CE or WE determines the start of a write cycle. A write is terminated by the earlier rising edge of CE or WE. The address must be held valid throughoutthe write cycle. WE must return to the high state for a Write cycle can be initiated. CE or WE is high during power on to perfect memory after Vcc reaches Vcc (min)but before the processor stabilizes.
FRESHNESS SEAL AND SHIPPING
DATA RETENTION
The IM1245Y - 100 is shipped from INNOVATIVEMICROTECHONOLOGY INC. with the lithium energy The IM 1245Y-100 provides full functional ca- source disconnected , guaranteeing full energy capac- pability for Vcc greater than 4.5V and write protects at ity. When Vcc is first applied at a level of greater than 4.25V. Data is retained in the absence of Vcc without 4.5 volts, the lithium energy source is enabled for bat- any additional support circuitry. The SRAM constantly monitors Vcc. The moment Vcc decays, the RAM au-tomatically write protects itself. All inputs to the RAMbecome “don’t care” and all outputs are in high imped-ance-state. As Vcc falls below approximately 3.0V thepower switching circuit connects the lithium energysource to RAM to retain data. During power-on, whenVcc rises above approximately 3.0V the power switch-ing circuit connects external Vcc to the RAM and dis-connects the lithium energy source. Normal RAM op-eration can resume after Vcc becomes greater than4.5V.
INNOVATIVE
IM1245Y-100
128K X 8 NO POWER SRAM
Electrical Characeteristics
Parameter
Description
Test conditons
Capacitance
Parameter
Description
Test conditons
INNOVATIVE
IM1245Y-100
128K X 8 NO POWER SRAM
Switching Characteristics over the operating range
Parameter Description
INNOVATIVE
IM1245Y-100
128K X 8 NO POWER SRAM
READ CYCLE
WRITE CYCLE 1
INNOVATIVE
IM1245Y-100
128K X 8 NO POWER SRAM
WRITE CYCLE 2
POWER – DOWN/ POWER –ON CONDITION
4.75V ————————————————————————————————————————————————— 3.2V —————————————————————————————————————————————————— During write cycle that is controlled by CE, output buffer is in high impedance state irrespective of whether OEis high or low level.
During write cycle that is controlled by WE, output buffer is in high impedance state if OE is high.
INNOVATIVE
IM1245Y-100
128K X 8 NO POWER SRAM
DIM IN INCHES MIN.

Source: http://www.ic72.net.cn/pdf_file/i/512765.pdf