M48T37Y-70MH1E STMicroelectronics, M48T37Y-70MH1E Datasheet
M48T37Y-70MH1E
Specifications of M48T37Y-70MH1E
M48T37Y-70MH1
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M48T37Y-70MH1E Summary of contents
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... Frequency test output for real-time clock software calibration ■ Automatic power-fail chip deselect and WRITE protection ■ Watchdog timer ■ WRITE protect voltage (V = Power-fail deselect voltage): PFD – M48T37Y 4 4.2 V ≤ V ≤ 4.5 V PFD – M48T37V 3 2.7 V ≤ V ≤ 3.0 V PFD ■ ...
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... Power-on reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 3.8 Programmable interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 3.9 Battery low flag . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 3.10 Initial power-on defaults . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 3.11 V noise and negative going transients . . . . . . . . . . . . . . . . . . . . . . . . . Maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . and AC parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 6 Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 7 Part numbering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 8 Environmental information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 9 Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 2/30 Doc ID 7019 Rev 9 M48T37Y, M48T37V ...
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... M48T37Y, M48T37V List of tables Table 1. Signal names . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Table 2. Operating modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Table 3. READ mode AC characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Table 4. WRITE mode AC characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Table 5. Register map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Table 6. Alarm repeat modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Table 7. Default values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Table 8. Absolute maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Table 9. Operating and AC measurement conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Table 10. Capacitance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Table 11. ...
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... SOH44 – 44-lead plastic small outline, 4-socket SNAPHAT Figure 15. SH – 4-pin SNAPHAT Figure 16. SH – 4-pin SNAPHAT Figure 17. Recycling symbols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 4/30 ® housing for 48 mAh battery & crystal, pack. outline . . . . . . . . . . . 25 ® housing for 120 mAh battery & crystal, pack. outline . . . . . . . . . . 26 Doc ID 7019 Rev 9 M48T37Y, M48T37V ® outline ...
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... M48T37Y, M48T37V 1 Description The M48T37Y/V TIMEKEEPER clock. The monolithic chip is available in a special package which provides a highly integrated battery-backed memory and real-time clock solution. The 44-lead, 330 mil SOIC package provides sockets with gold-plated contacts at both ends for direct connection to a separate SNAPHAT housing containing the battery and crystal. ...
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... Chip enable Output enable WRITE enable Supply voltage Ground Not connected internally RST A14 5 40 A12 M48T37Y NC 12 M48T37V WDI DQ0 18 27 DQ1 19 26 DQ2 Doc ID 7019 Rev 9 M48T37Y, M48T37V IRQ/FT W A13 A8 A9 A11 A10 E NC DQ7 DQ6 DQ5 DQ4 DQ3 NC AI02174 ...
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... M48T37Y, M48T37V Figure 3. Block diagram 32,768 Hz CRYSTAL LITHIUM CELL IRQ/FT WDI OSCILLATOR AND CLOCK CHAIN POWER VOLTAGE SENSE V PFD AND SWITCHING CIRCUITRY V CC RST Doc ID 7019 Rev 9 Description BiPORT SRAM ARRAY A0-A14 32,752 x 8 DQ0-DQ7 SRAM ARRAY AI03253 7/30 ...
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... READ mode The M48T37Y the READ mode whenever WRITE enable (W) is high and chip enable (E) is low. The unique address specified by the 15 address inputs defines which one of the 32,752 bytes of data accessed. Valid data will be available at the data I/O pins within address access time (t and output enable (G) access times are also satisfied ...
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... M48T37Y, M48T37V met, valid data will be available after the latter of the chip enable access time (t output enable access time (t The state of the eight three-state data I/O signals is controlled by E and G. If the outputs are activated before t If the address inputs are changed while E and G remain active, output data will remain valid for output data hold time (t Figure 4 ...
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... Operation modes 2.2 WRITE mode The M48T37Y the WRITE mode whenever W and E are low. The start of a WRITE is referenced from the latter occurring falling edge WRITE is terminated by the earlier rising edge The addresses must be held valid throughout the cycle must return high for a minimum the initiation of another READ or WRITE cycle ...
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... V supply lines is recommended. When V power to the internal battery which preserves data and powers the clock. The internal button cell will maintain data in the M48T37Y/V for an accumulated period of at least 7 years at room temperature when V above V ...
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... The STOP bit is the MSB of the seconds register. Setting '1' stops the oscillator. When reset to a '0,' the M48T37Y/V oscillator starts within one second. Note not necessary to set the WRITE bit when setting or resetting the FREQUENCY TEST bit (FT) or the STOP bit (ST) ...
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... M48T37Y, M48T37V Table 5. Register map Address D7 7FFFh 7FFEh 0 7FFDh 0 7FFCh 0 7FFBh 0 7FFAh 0 7FF9h ST 7FF8h W 7FF7h WDS 7FF6h AFE 7FF5h RPT4 7FF4h RPT3 7FF3h RPT2 7FF2h RPT1 7FF1h 7FF0h WDF Keys Sign bit FT = Frequency test bit R = READ bit W = WRITE bit ST = Stop bit ...
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... Registers 7FF5h-7FF2h contain the alarm settings. The alarm can be configured to go off at a predetermined time on a specific day of the month or repeat every day, hour, minute, or second. It can also be programmed to go off while the M48T37Y the battery backup mode of operation to serve as a system wake-up call. ...
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... IRQ/FT 3.5 Calibrating the clock The M48T37Y/V is driven by a quartz controlled oscillator with a nominal frequency of 32,768 Hz. The devices are tested not to exceed ±35 ppm (parts per million) oscillator frequency error at 25 °C, which equates to about ±1.53 minutes per month. With the calibration bits properly set, the accuracy of each M48T37Y/V improves to better than +1/– ...
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... Note: Accuracy of timer is within ± the selected resolution. If the processor does not reset the timer within the specified period, the M48T37Y/V sets the watchdog flag (WDF) and generates a watchdog interrupt or a microprocessor reset. WDF is reset by reading the flags register (Address 7FF0h). ...
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... Programmable interrupts The M48T37Y/V provides two programmable interrupts: an alarm and a watchdog. When an interrupt condition occurs, the M48T37Y/V sets the appropriate flag bit in the flag register 7FF0h. The interrupt enable bits (AFE and ABE) in 7FF6h and the watchdog steering (WDS) bit in 7FF7h allow the interrupt to activate the IRQ/FT pin. ...
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... Note: This will cause the clock to lose time during the interval the battery/crystal is removed. Battery monitoring is a useful technique only when performed periodically. The M48T37Y/V only monitors the battery when a nominal V which require extensive durations in the battery back-up mode should be powered-up periodically (at least once every few months) in order for this technique to be beneficial ...
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... M48T37Y, M48T37V one volt. These negative spikes can cause data corruption in the SRAM while in battery backup mode. To protect from these voltage spikes recommended to connect a Schottky diode from V 1N5817 is recommended for through hole and MBRS120T3 is recommended for surface mount. Figure 9. Supply voltage protection Figure 10 ...
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... Do NOT wave solder SOIC to avoid damaging SNAPHAT 20/30 Parameter Grade 1 Grade 6 ® SNAPHAT off, CC SOH44 M48T37Y M48T37V M48T37Y M48T37V ® sockets. Doc ID 7019 Rev 9 M48T37Y, M48T37V Value Unit °C – °C – °C –55 to 150 °C 260 °C –0 –0.3 to 4.6 V – ...
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... M48T37Y, M48T37V 5 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 measurement conditions listed in the relevant tables. Designers should check that the operating conditions in their projects match the measurement conditions when using the quoted parameters ...
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... OUT CC Outputs open – 0 –0 – °C or – ° through a 100 kΩ resistor. tFB tDR DON'T CARE HIGH-Z Doc ID 7019 Rev 9 M48T37Y, M48T37V M48T37Y M48T37V –70 –100 Max Min Max ±1 ±1 ±1 ± 0.8 –0.3 0 0 0.4 ...
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... M48T37Y, M48T37V Table 12. Power down/up AC characteristics Symbol ( PFD ( PFD PFD ( REC PFD 1. Valid for ambient operating temperature: T (except where noted (max PFD PFD until 200 µs after (min PFD (min for industrial temperature range - grade 6 device. REC Table 13. Power down/up trip points DC characteristics ...
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... Doc ID 7019 Rev 9 M48T37Y, M48T37V ® outline ® , package inches Typ Min 0.002 0.092 0.014 0.006 0.697 0.324 0.032 – 0.126 0.453 0.016 0° ...
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... M48T37Y, M48T37V Figure 15. SH – 4-pin SNAPHAT Note: Drawing is not to scale. Table 15. SH – 4-pin SNAPHAT mechanical data Symbol ® housing for 48 mAh battery & crystal, pack. outline ® housing for 48 mAh battery & crystal, package mm Typ Min Max 9.78 6.73 7 ...
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... Min Max 10.54 8.00 8.51 7.24 8.00 0.38 0.46 0.56 21.21 21.84 17.27 18.03 15.55 15.95 3.20 3.61 2.03 2.29 Doc ID 7019 Rev 9 M48T37Y, M48T37V inches Typ Min 0.315 0.285 0.018 0.835 0.680 0.612 0.126 0.080 SHTK-A Max 0.415 .0335 0.315 ...
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... M48T37Y, M48T37V 7 Part numbering Table 17. Ordering information scheme Example: Device type M48T Supply voltage and write protect voltage 37Y = V = 4 37V = V = 3 Speed – (37Y) –10 = 100 ns (37V) Package ( SOH44 Temperature range °C ( – °C Shipping method blank = tubes (not for new design - use E) ® ...
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... Recycle or dispose of batteries in accordance with the battery manufacturer's instructions and local/national disposal and recycling regulations. Please refer to the following web site address for additional information regarding compliance statements and waste recycling www.st.com/rtc, then select "Lithium Battery Recycling" from "Related Topics". 28/30 Doc ID 7019 Rev 9 M48T37Y, M48T37V ...
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... M48T37Y, M48T37V 9 Revision history Table 19. Document revision history Date Revision Dec-1999 07-Feb-2000 11-Jul-2000 19-Jun-2001 06-Aug-2001 15-Jan-2002 20-May-2002 31-Mar-2003 01-Apr-2004 08-Feb-2006 03-Aug-2007 24-Mar-2009 02-Aug-2010 1 First issue From preliminary data to datasheet; battery low flag paragraph 2 changed; 100 ns speed class identifier changed 2.1 t changed (Table ) ...
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... Australia - Belgium - Brazil - Canada - China - Czech Republic - Finland - France - Germany - Hong Kong - India - Israel - Italy - Japan - Malaysia - Malta - Morocco - Philippines - Singapore - Spain - Sweden - Switzerland - United Kingdom - United States of America 30/30 Please Read Carefully: © 2010 STMicroelectronics - All rights reserved STMicroelectronics group of companies www.st.com Doc ID 7019 Rev 9 M48T37Y, M48T37V ...