M48T35 TIMEKEEPER SRAM_BDTIC 代理M48T35

M48T35 TIMEKEEPER SRAM

The M48T35/Y TIMEKEEPER®RAM is a 32 Kb x 8 non-volatile static RAM and real-time clock. The monolithic chip is available in two special packages to provide a highly integrated battery-backed memory and real-time clock solution.

The M48T35/Y is a non-volatile pin and function equivalent to any JEDEC standard 32 Kb x 8 SRAM. It also easily fits into many ROM, EPROM, and EEPROM sockets, providing the non-volatility of PROMs without any requirement for special WRITE timing or limitations on the number of WRITEs that can be performed.

The 28-pin, 600 mil DIP CAPHAT™houses the M48T35/Y silicon with a quartz crystal and a long life lithium button cell in a single package.

The 28-pin, 330 mil SOIC provides sockets with gold plated contacts at both ends for direct connection to a separate SNAPHAT®housing containing the battery and crystal. The unique design allows the SNAPHAT battery package to be mounted on top of the SOIC package after the completion of the surface mount process. Insertion of the SNAPHAT housing after reflow prevents potential battery and crystal damage due to the high temperatures required for device surface-mounting. The SNAPHAT housing is keyed to prevent reverse insertion. The SOIC and battery/crystal packages are shipped separately in plastic anti-static tubes or in tape & reel form.

For the 28-lead SOIC, the battery/crystal package (e.g., SNAPHAT) part number is “M4T28-BR12SH”.

技术特性

Integrated, ultra low power SRAM, real-time clock, power-fail control circuit and battery
BYTEWIDE™RAM-like clock access
BCD coded year, month, day, date, hours, minutes, and seconds
Frequency test output for real-time clock
Automatic power-fail chip deselect and WRITE protection
WRITE protect voltages VPFD= power-fail deselect voltage):
- M48T35: VCC= 4.75 to 5.5 V; 4.5 V ≤ VPFD≤ 4.75 V
- M48T35Y: VCC= 4.5 to 5.5 V; 4.2 V ≤ VPFD≤ 4.5 V
Self-contained battery and crystal in the CAPHAT™DIP package
SOIC package provides direct connection for a SNAPHAT® housing containing the battery and crystal
SNAPHAT® housing (battery and crystal) is replaceable
Pin and function compatible with JEDEC standard 32 Kb x 8 SRAMs
RoHS compliant
- Lead-free second level interconnect

功能框图

M48T35 订购信息

订购型号	产品状态	美金价格	数量	封装	包装形式	温度范围	材料声明
M48T35-150PC1	Active			PDIP 28 .7	Tube	0 °C-70°C	M48T35-150PC1
M48T35-70PC1	Active			PDIP 28 .7	Tube	0 °C-70°C	M48T35-70PC1

DATASHEET

描述	版本	大小
M48T35 : DS0524: 5 V, 256 Kbit (32 Kb x 8) TIMEKEEPER® SRAM	10	473KB

APPLICATION NOTES

描述	版本	大小
AN968: VMEbus TIMEKEEPER® requirements	1	38KB
AN925: Time update in ST's TIMEKEEPER® devices	1	31KB
AN923: TIMEKEEPER® rolling into the year 2000 (21st century, Y2K)	1	20KB
AN1012: Predicting the battery life and data retention period of NVRAMs and serial RTCs	4	440KB
AN934: How to use the digital calibration feature in TIMEKEEPER® and serial real-time clock (RTC) products	4	124KB
AN1011: Battery technology used in NVRAM and real-time clock (RTC) products from ST	4	249KB
AN1009: 'Negative undershoot' NVRAM data corruption	1	34KB