m48t18 STMicroelectronics, m48t18 Datasheet
m48t18
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m48t18 Summary of contents
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... Automatic power-fail chip deselect and write protection ■ Write protect V = Power-fail deselect voltage): PFD – M48T08 4.75 to 5.5V CC 4.5V V 4.75V PFD – M48T18/T08Y 4.5 to 5.5V CC 4.2V V 4.5V PFD ■ Software controlled clock calibration for high accuracy applications ■ Self-contained battery and crystal in the CAPHAT™ dip package ■ ...
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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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... WRITE enable Supply voltage Ground INT A12 A11 M48T08 A10 M48T18 DQ7 DQ0 11 18 DQ6 DQ1 12 17 DQ5 DQ2 13 16 DQ4 DQ3 AI01182 ...
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Figure 3. SOIC connections Figure 4. Block diagram OSCILLATOR AND CLOCK CHAIN 32,768 Hz CRYSTAL LITHIUM CELL VOLTAGE SENSE SWITCHING V CC INT 1 28 A12 ...
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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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... READ or WRITE Cycle. Data-in must be valid t of WRITE and remain valid for t Cycles to avoid bus contention; however, if the output bus has been activated by a low on E1 and G and a high on E2, a low on W will disable the outputs t 10/30 M48T08/M48T18/T08Y (1) –100/–10 (T08Y) Min 100 ...
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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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... V is not less than t . The M48T08/18/08Y may respond to transient noise spikes reach into the deselect window during the time the device is sampling V decoupling of the power supply lines is recommended. 12/30 M48T08/M48T18/T08Y (1) –100/–10 (T08Y) Min 100 0 0 ...
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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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... The STOP Bit (ST) is the MSB of the seconds register. Setting '1' stops the oscillator. The M48T08/18/08Y (in the PCDIP28 package) is shipped from STMicroelectronics with the STOP Bit set to a '1.' When reset to a '0,' the M48T08/18/08Y oscillator starts within one second. ...
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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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... These are stress ratings only and operation of the device at these or any other conditions above those indicated in the Operating sections of this specification is not implied. Exposure to Absolute Maximum Rating conditions for extended periods may affect device reliability. Refer also to the STMicroelectronics SURE Program and other relevant quality documents. Table 6. ...
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... Effective capacitance measured with power supply at 5V; sampled only, not 100% tested 25° 1MHz. 3. Outputs deselected. 20/30 M48T08 ) 4. 100 1.5 DEVICE UNDER TEST includes JIG capacitance (1)(2) Parameter M48T18/T08Y Unit 4 100 1.5 5V 1.8k OUT 100pF AI01019 Min Max ° ...
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... V = 4.75 to 5.5V or 4.5 to 5.5V (except where noted tDR tFB tPFX DON'T CARE HIGH-Z (min). Some systems may perform inadvertent WRITE PFD (min) but before normal system operations begin. Even PFD M48T08/M48T18/T08Y Unit Min Max ±1 µA ±1 µ – ...
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... V A (min) fall time of less than t may result in deselection/write protection not occurring F passes V (min). PFD may cause corruption of RAM data. FB (1)(2) Parameter M48T08 M48T18/T08Y . 70° 8.5 years (typ) at 70°C. Requires use of M4T32-BR12SH SNAPHAT DR Min Max 0 300 10 0 ...
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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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Part numbering Table 16. Ordering information scheme Example: Device type M48T Supply Voltage and Write Protect Voltage ( 4.75 to 5.5V 18/08Y = V = 4.5 to 5.5V Speed –100 = 100ns ...
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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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Revision history Table 18. Document revision history Date Revision Dec-1999 1.0 07-Feb-2000 2.0 11-Jul-2000 2.1 16-Jul-2001 3.0 01-Aug-2001 3.1 21-Dec-2001 3.2 06-Mar-2002 3.3 20-May-2002 3.4 29-Aug-2002 3.5 28-Mar-2003 4.0 10-Dec-2003 5.0 30-Mar-2004 6.0 13-Dec-2005 7.0 04-Jul-2007 8.0 Changes First Issue ...
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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 time, without notice. All ST products are sold pursuant to ST’s terms and conditions of sale. ...