M48T08Y STMICROELECTRONICS [STMicroelectronics], M48T08Y Datasheet
M48T08Y
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M48T08Y Summary of contents
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... Pin and function compatible with DS1643 and JEDEC standard 8K x8 SRAMs ■ RoHS compliant – Lead-free second level interconnect July 2007 5V, 64Kbit ( TIMEKEEPER Rev 8 M48T08 M48T08Y, M48T18 ® SRAM 28 1 PCDIP28 (PC) battery/crystal CAPHAT SNAPHAT (SH) battery/crystal 28 1 SOH28 (MH) www ...
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Contents Summary description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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List of tables Table 1. Signal names . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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List of figures Figure 1. Logic diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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... Figure 1. Logic diagram ® RAM non-volatile static RAM and real ® housing containing the battery and crystal. The A0-A12 W M48T08 M48T08Y E1 M48T18 Table 17 on page 28). DQ0-DQ7 INT AI01020 5/30 ...
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Table 1. Signal names A0-A12 DQ0-DQ7 INT Figure 2. DIP connections 6/30 Address inputs Data inputs / outputs Power fail interrupt (open drain) Chip enable 1 Chip enable 2 Output enable WRITE ...
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... CLOCK CHAIN 32,768 Hz CRYSTAL LITHIUM CELL VOLTAGE SENSE SWITCHING V CC INT 1 28 A12 M48T08Y DQ0 11 18 DQ1 12 17 DQ2 AI01021B POWER V PFD AND CIRCUITRY INT V CC ...
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Operation modes As Figure 4 on page 7 oscillator of the M48T08/18/08Y are integrated on one silicon chip. The two circuits are interconnected at the upper eight memory locations to provide user accessible BYTEWIDE™ clock information in the bytes with ...
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Chip Enable Access times (t Output Enable Access time (t The state of the eight three-state Data I/O signals is controlled by E1, E2 and G. If the outputs are activated ...
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Table 3. Read mode AC characteristics Symbol Parameter t READ Cycle Time AVAV t Address Valid to Output Valid AVQV t Chip Enable 1 Low to Output Valid E1LQV t Chip Enable 2 High to Output Valid E2HQV t Output ...
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Figure 6. Write enable controlled, write AC waveform A0-A12 DQ0-DQ7 Figure 7. Chip enable controlled, write AC waveforms A0-A12 tAVE1L E1 tAVE2H E2 W DQ0-DQ7 tAVAV VALID tAVWH tAVE1L tAVE2H tWLWH tAVWL tWLQZ tWHDX DATA INPUT tDVWH ...
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Table 4. Write mode AC characteristics Symbol Parameter t WRITE Cycle Time AVAV t Address Valid to WRITE Enable Low AVWL t Address Valid to Chip Enable 1 Low AVE1L t Address Valid to Chip Enable 2 High AVE2H t ...
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When V drops below V CC preserves data and powers the clock. The internal button cell will maintain data in the M48T08/18/08Y for an accumulated period of at least 10 years when V Note: Requires use of M4T32-BR12SH SNAPHAT As ...
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Clock operations Reading the clock Updates to the TIMEKEEPER prevent reading data in transition. The BiPORT™ TIMEKEEPER cells in the RAM array are only data registers and not the actual clock counters, so updating the registers can be halted without ...
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Table 5. Register map Address D7 1FFFh 1FFEh 0 1FFDh 0 1FFCh 0 1FFBh 0 1FFAh 0 1FF9h ST 1FF8h W Note SIGN Bit FT = FREQUENCY TEST Bit (Set to '0' for normal clock operation ...
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Calibration Byte found in the Control Register. Adding counts speeds the clock up, subtracting counts slows the clock down. The Calibration Byte occupies the five lower order bits in the Control register. This byte can be set ...
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Figure 8. Crystal accuracy across temperature ppm 20 0 -20 -40 -60 -80 -100 0 5 Figure 9. Clock calibration NORMAL POSITIVE CALIBRATION NEGATIVE CALIBRATION V noise and negative going transients CC I transients, including those produced by output switching, ...
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MBRS120T3 is recommended for surface mount. Figure 10. Supply voltage protection 18/ 0.1 F DEVICE V SS AI02169 ...
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Maximum rating Stressing the device above the rating listed in the “Absolute Maximum Ratings” table may cause permanent damage to the device. These are stress ratings only and operation of the device at these or any other conditions above those ...
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DC and AC parameters This section summarizes the operating and measurement conditions, as well as the DC and AC characteristics of the device. The parameters in the following DC and AC Characteristic tables are derived from tests performed under the ...
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Table 9. DC characteristics Symbol Parameter I Input Leakage Current LI (2) I Output Leakage Current LO I Supply Current CC (3) I Supply Current (Standby) TTL CC1 (3) I Supply Current (Standby) CMOS CC2 V Input Low Voltage IL ...
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Table 10. Power down/up AC characteristics Symbol Down ( (max PFD ( (min PFD t V (min PFD t V ...
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Package mechanical data In order to meet environmental requirements, ST offers these devices in ECOPACK® packages. These packages have a Lead-free second level interconnect. The category of second Level Interconnect is marked on the package and on the inner box ...
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Figure 14. SOH28 – 28-lead plastic small outline, 4-socket battery SNAPHAT, package outline B Note: Drawing is not to scale. Table 13. SOH28 – 28-lead plastic SO, 4-socket battery SNAPHAT, package mech. data Symb Typ ...
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Figure 15. SH – 4-pin SNAPHAT housing for 48mAh battery & crystal, package outline Note: Drawing is not to scale. Table 14. SH – 4-pin SNAPHAT housing for 48mAh battery & crystal, package mech. data Symb Typ ...
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Figure 16. SH – 4-pin SNAPHAT housing for 120mAh battery & crystal, package outline Note: Drawing is not to scale. Table 15. SH – 4-pin SNAPHAT housing for 120mAh battery & crystal, package mech data. Symb Typ ...
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... The SOIC package (SOH28) requires the SNAPHAT under the part number“M4TXX-BR12SH” in plastic tube or “M4TXX-BR12SHTR” in Tape & Reel form (see Table 17). The M48T08Y part is offered in the SOH28 (SNAPHAT) package only. Caution: Do not place the SNAPHAT battery package “M4TXX-BR12SH” in conductive foam as it will drain the lithium button-cell battery ...
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Table 17. SNAPHAT battery table Part Number M4T28-BR12SH M4T32-BR12SH 28/30 Description Lithium Battery (48mAh) SNAPHAT Lithium Battery (120mAh) SNAPHAT Package SH SH ...
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... Reformatted; SNAPHAT battery table added temp./voltage info. to tables (Table Reference to App. Note corrected in “Calibrating the Clock” section Changes to text in document to reflect addition of M48T08Y option Fix Ordering Information table and add to footnote Modify reflow time and temperature footnotes t specification temperature updated DR v2.2 template applied ...
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Information in this document is provided solely in connection with ST products. STMicroelectronics NV and its subsidiaries (“ST”) reserve the right to make changes, corrections, modifications or improvements, to this document, and the products and services described herein at any ...