m41st95w STMicroelectronics, m41st95w Datasheet
m41st95w
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m41st95w Summary of contents
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... AUTOMATIC SWITCH-OVER AND DESELECT CIRCUITRY CHOICE OF POWER-FAIL DESELECT VOLTAGES: – M41ST95Y 4.5 to 5.5V CC 4.20V V 4.50V PFD – M41ST95W 2.7 to 3.6V CC 2.55V V 24.70V PFD 1.25V REFERENCE (FOR PFI/PFO) COUNTERS FOR TENTHS/HUNDREDTHS OF SECONDS, SECONDS, MINUTES, HOURS, DAY, DATE, MONTH, YEAR, AND CENTURY 44 BYTES OF GENERAL PURPOSE RAM ...
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... M41ST95Y*, M41ST95W TABLE OF CONTENTS FEATURES SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Figure 1. 28-pin SOIC Package Figure 2. 28-pin (300mil) SOIC Package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 SUMMARY DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Figure 3. Logic Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Table 1. Signal Names . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Figure 4. 28-pin SOIC Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Figure 5. 28-pin, 300mil SOIC (MX) Connections Figure 6. Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Figure 7. Hardware Hookup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 SPI Bus Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Signal Description ...
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... Figure 25.SOX28 – 28-lead Plastic Small Outline, 300mils, Embedded Crystal, Outline . . . . . . . . 32 Table 18. SOX28 – 28-lead Plastic Small, 300mils, Embedded Crystal, Package Mech. Data . . . 32 PART NUMBERING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Table 19. Ordering Information Scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Table 20. SNAPHAT Battery Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 REVISION HISTORY Table 21. Document Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 M41ST95Y*, M41ST95W 3/35 ...
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... M41ST95Y*, M41ST95W SUMMARY DESCRIPTION The M41ST95Y/W Serial TIMEKEEPER is a low power, 512-bit static CMOS SRAM orga- nized as 64 words by 8 bits. A built-in 32,768Hz oscillator (external crystal controlled) and 8 bytes of the SRAM (see Table 4., page the clock/calendar function and are configured in binary coded decimal (BCD) format. ...
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... BAT Note: 1. For SOX28 package only. 2. Available only in 28-pin, 300mil SOIC (MX) package. M41ST95Y*, M41ST95W Conditioned Chip Enable Output External Chip Enable Chip Enable Interrupt/Frequency Test/Out Output (Open Drain) Reset Output (Open Drain) Reset 1 Input Reset 2 Input Serial Clock Input ...
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... M41ST95Y*, M41ST95W Figure 4. 28-pin SOIC Connections SQW M41ST95Y 22 M41ST95W WDI 8 21 RSTIN1 9 20 RSTIN2 PFO 6/35 Figure 5. 28-pin, 300mil SOIC (MX) Connections (1) NF IRQ/FT/OUT ...
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... REAL TIME CLOCK CALENDAR 44 BYTES USER RAM SPI RTC w/ALARM & CALIBRATION OUTPUT DRIVER FREQUENCY TEST WATCHDOG SQUARE WAVE COMPARE V BL COMPARE V SO COMPARE V PFD COMPARE M41ST95Y*, M41ST95W AFE OUT FT IRQ/FT/OUT WDS SQW F 32k V OUT BL POR RST E CON PFO (1) (2) (1) AI06371 7/35 ...
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... M41ST95Y*, M41ST95W Figure 7. Hardware Hookup SPI Interface with (CPOL, CPHA) (1) = ('0','0') or ('1','1') Master (ST6, ST7, ST9, ST10, Others) CS3 CS2 CS1 Note: 1. CPOL (Clock Polarity) and CPHA (Clock Phase) are bits that may be set in the SPI Control Register of the MCU. ...
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... There is one clock for each bit transferred. Ad- dress and data bits are transferred in groups of eight bits. Due to memory size the second most significant address bit is a Don’t Care (address bit 6). M41ST95Y*, M41ST95W CC (min). For more information REC 8). (CPOL, CPHA) = ('0', '0') or (CPOL, CPHA) = ('1', '1') ...
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... M41ST95Y*, M41ST95W Signal Description Serial Data Output (SDO). The output pin is used to transfer data serially out of the Memory. Data is shifted out on the falling edge of the serial clock. Serial Data Input (SDI). The input pin is used to transfer data serially into the device. Instructions, addresses, and the data to be written, are each re- ceived this way ...
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... MSB OUT SDO ADDR. LSB IN SDI Figure 11. WRITE Cycle Timing: RTC and External SRAM Control Signals EX E CON tELCH tCHEH tCHDX tCLCH tDLDH tDHDL tCH tEXPD tEXPD M41ST95Y*, M41ST95W tEHEL tEHCH tCHCL LSB IN AI04633 tCL tEHQZ LSB OUT tQLQH tQHQL AI04634 AI03663 11/35 ...
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... M41ST95Y*, M41ST95W Table 3. AC Characteristics Symbol f Serial Clock Input Frequency SCL (2) Clock High t CH (3) Clock Transition (Fall Time) t CHCL t Serial Clock Input High to Input Data Transition CHDX t Serial Clock Input High to Chip Enable High CHEH (2) Clock Low t CL (3) Clock Transition (Rise Time) ...
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... RAM address (08h to 3Fh). Note: This is true both in READ and WRITE mode DATA OUT (BYTE MSB M41ST95Y*, M41ST95W 22 DATA OUT (BYTE MSB AI04635 13/35 ...
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... M41ST95Y*, M41ST95W Figure 13. WRITE Mode Sequence SCL 7 BIT ADDR W/R BIT SDI MSB SDO Data Retention Mode With valid V applied, the M41ST95Y/W can be CC accessed as described above with READ or WRITE Cycles. Should the supply voltage decay, the M41ST95Y/W will automatically deselect, ...
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... The update will resume either due to a deselect condition or when the pointer in- crements to a non-clock or RAM address. TIMEKEEPER and Alarm Registers store data in BCD. Control, Watchdog and Square Wave Reg- isters store data in Binary format. M41ST95Y*, M41ST95W Table 15/35 ...
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... M41ST95Y*, M41ST95W ® Table 4. TIMEKEEPER Register Map Addr D7 D6 00h 0.1 Seconds 01h ST 10 Seconds 02h 0 10 Minutes 03h CEB CB 04h TR 0 05h 0 0 06h 0 0 07h 10 Years 08h OUT FT 09h WDS BMB4 BMB3 0Ah AFE SQWE ABE 0Bh RPT4 RPT5 0Ch ...
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... It should also be noted that if the last address writ- ten is the “Alarm Seconds,” the address pointer will increment to the Flag address, causing this sit- uation to occur. M41ST95Y*, M41ST95W For example, a reading Table 5., page 18 shows the possible ...
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... M41ST95Y*, M41ST95W To disable the alarm, write '0' to the Alarm Date Register and to RPT1-5. The IRQ/FT/OUT output is cleared by a READ to the Flags Register as shown in Figure 14. A subsequent READ of the Flags Register is necessary to see that the value of the Alarm Flag has been reset to '0.' The IRQ/FT/OUT pin can also be activated in the battery back-up mode ...
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... Watchdog Register is cleared. If the watchdog function is set to output to the IRQ/FT/OUT pin and the Frequency Test (FT) function is activated, the watchdog function pre- vails and the Frequency Test function is denied. M41ST95Y*, M41ST95W tREC HIGH-Z AI03920 if not used. In order to per- ...
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... M41ST95Y*, M41ST95W Square Wave Output The M41ST95Y/W offers the user a programma- ble square wave function which is output on the SQW pin. RS3-RS0 bits located in 13h establish the square wave output frequency. These fre- quencies are listed in Table 6. Once the selection Table 6. Square Wave Output Frequency ...
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... RSTIN1 and RSTIN2 are each internally pulled through a 100k tRLRH1 tRLRH2 tR1HRH (1) Parameter = –40 to 85° 4.5 to 5.5V or 2.7 to 3.6V (except where noted 23) M41ST95Y*, M41ST95W and t RLRH1 resistor. tR2HRH AI03665 Min Max 200 100 ...
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... M41ST95Y*, M41ST95W Power-fail INPUT/OUTPUT The Power-Fail Input (PFI) is compared to an in- ternal reference voltage (1.25V). If PFI is less than the power-fail threshold (V PFI Output (PFO) will go low. This function is intended for use as an under-voltage detector to signal a failing power supply. Typically PFI is connected through an external voltage divider (see Figure 17) ...
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... Min Out M41ST95Y*, M41ST95W applied to the device applied to the device. Thus appli- CC refers to the automatic continuation of REC reaches V CC Bit will allow the user to REC Time Max (1) 98 200 2000 FT AFE ABE ...
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... M41ST95Y*, M41ST95W Figure 18. Crystal Accuracy Across Temperature Frequency (ppm –20 –40 –60 –80 –100 –120 –140 –160 –40 –30 –20 Figure 19. Calibration Waveform NORMAL POSITIVE CALIBRATION NEGATIVE CALIBRATION 24/ – –0.036 ppm ± – ...
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... STMicroelectronics SURE Program and other rel- evant quality documents. Parameter Off, Oscillator Off) CC M41ST95Y M41ST95W Lead-free lead finish Standard (SnPb) lead finish M41ST95Y*, M41ST95W Refer also to Value Unit –55 to 125 °C –0 –0.3 to 4.6 V (1) 260 ° ...
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... M41ST95Y*, M41ST95W DC AND AC PARAMETERS This section summarizes the operating and mea- surement 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 Measure- Table 11. DC and AC Measurement Conditions V Supply Voltage ...
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... V = 3V(W) CC PFI Rising 20 2.5 = –40 to 85° 4.5 to 5.5V or 2.7 to 3.6V (except where noted open. through 100K resistor. WDI internally pulled-down specification. CC (max) may be considered M41ST95Y*, M41ST95W M41ST95W Max Min Typ Max 550 400 550 50 2 1.4 1.4 ±1 25 –25 2 ±1 175 ...
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... M41ST95Y*, M41ST95W Figure 21. Power Down/Up Mode AC Waveforms PFD (max) V PFD (min tPD PFO INPUTS RECOGNIZED RST OUTPUTS VALID (PER CONTROL INPUT) E CON Table 14. Power Down/Up AC Characteristics Symbol (2) V (max PFD PFD F (3) V (min PFD (min ...
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... millimeters Min Max 3.05 0.05 0.36 2.34 2.69 0.36 0.51 0.15 0.32 17.71 18.49 8.23 8.89 – – 3.20 3.61 11.51 12.70 0.41 1.27 0° 8° 28 0.10 M41ST95Y*, M41ST95W inches Typ Min 0.002 0.092 0.014 0.006 0.697 0.324 0.050 – 0.126 0.453 0.016 0° 28 Max 0.120 0.014 0.106 0.020 0.012 0.728 0.350 – 0.142 0.500 0.050 8° ...
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... M41ST95Y*, M41ST95W Figure 23. SH – 4-pin SNAPHAT Housing for 48mAh Battery & Crystal, Package Outline Note: Drawing is not to scale. Table 16. SH – 4-pin SNAPHAT Housing for 48mAh Battery & Crystal, Package Mechanical Data Symbol Typ 30/ ...
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... Table 17. SH – 4-pin SNAPHAT Housing for 120mAh Battery & Crystal, Package Mech. Data Symbol Typ millimeters Min Max 10.54 6.73 7.24 6.48 6.99 0.38 0.46 0.56 21.21 21.84 14.22 14.99 15.55 15.95 3.20 3.61 2.03 2.29 M41ST95Y*, M41ST95W SHTK-A inches Typ Min Max 0.4150 0.2650 0.2850 0.2551 0.2752 0.0150 0.0181 0.0220 0.8350 0.8598 0.5598 0.5902 0.6122 0.6280 0.1260 0.1421 0.0799 0.0902 A2 31/35 ...
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... M41ST95Y*, M41ST95W Figure 25. SOX28 – 28-lead Plastic Small Outline, 300mils, Embedded Crystal, Outline SO-E Note: Drawing is not to scale. Table 18. SOX28 – 28-lead Plastic Small, 300mils, Embedded Crystal, Package Mech. Data Symbol Typ ddd 32/ ...
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... Lithium Battery (48mAh) and Crystal SNAPHAT M4T32-BR12SH Lithium Battery (120mAh) and Crystal SNAPHAT M41ST V 4.50V PFD V 2.70V PFD ® ), Tubes ® ), Tape & Reel ® battery package which is ordered separately under the part number “M4TXX- Description M41ST95Y*, M41ST95W 95Y MH 6 Package SH SH 33/35 ...
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... Update Maximum ratings (Table 10) M41ST95, 41ST95, ST95, M41ST95Y, 41ST95Y, ST95Y, M41ST95W, 41ST95W, ST95W, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, ...
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