m41t315v STMicroelectronics, m41t315v Datasheet
m41t315v
Available stocks
Related parts for m41t315v
m41t315v Summary of contents
Page 1
... Automatic switch-over and deselect circuitry ■ Choice of power-fail deselect voltages power-fail deselect voltage) PFD (a) – M41T315Y : V = 4.5 to 5.5V CC 4.25V ≤ V ≤ 4.50V PFD – M41T315V 3.0 to 3.6V CC 2.80V ≤ V ≤ 2.97V PFD – M41T315W 2.7 to 3.3V CC 2.60V ≤ V ≤ 2.70V PFD ■ No address space required to communicate with RTC ■ ...
Page 2
Contents 1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
Page 3
... List of tables Table 1. Signal names . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Table 2. Operating modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Table 3. AC electrical characteristics (M41T315Y Table 4. AC electrical characteristics (M41T315V/ Table 5. RTC register map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Table 6. Ablolute maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Table 7. DC and AC measurement conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Table 8. Capacitance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Table 9. DC characteristics Table 10. Crystal electrical characteristics (externally supplied Table 11 ...
Page 4
List of figures Figure 1. Logic diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
Page 5
Description The M41T315Y/V/W RTC Supervisor is a combination of a CMOS TIMEKEEPER nonvolatile memory supervisor. Power is constantly monitored by the memory supervisor. In the event of power instability or absence, an external battery maintains the timekeeping operation and ...
Page 6
... WE V CCO V CCI 6/30 V CCI V CCO D (1) XI (1) XO M41T315Y M41T315V WE M41T315W CEI OE RST (1) V BAT V SS 32.768 KHz crystal connection Data input Data output Reset input Chip enable output Chip enable input Battery input Output enable input WRITE enable input ...
Page 7
... OE M41T315W CEI CEO AI03909 CCI CCO M41T315Y RST M41T315V M41T315W CEI CEO AI03910 7/30 ...
Page 8
Figure 4. Block diagram CEO CEI OE WE RST CCI 8/30 XO 32,768 Hz CLOCK/CALENDAR LOGIC CRYSTAL XI UPDATE READ WRITE TIMEKEEPER REGISTER CONTROL LOGIC POWER-FAIL ACCESS ENABLE SEQUENCE DETECTOR I/O DATA BUFFERS INTERNAL V CC POWER-FAIL ...
Page 9
Figure 5. M41T315Y/V/W to RAM/clock interface A0- RST A0-An DATA I/O CMOS WE SRAM CEO V CCO M41T315Y/V/W CEI Q RST V CCI V BAT ...
Page 10
Operation Figure 6 on page 11 describe the signals and functions. Communication with the clock is established by pattern recognition of a serial bit stream of 64 bits which must be matched by executing 64 consecutive WRITE cycles containing ...
Page 11
Table 2. Operating modes Mode V CC Deselect 4.5 to 5.5V or WRITE 3.0 to 3.6V READ or 2.7 to 3.3V READ (1) Deselect (min) SO PFD (1) ≤ V Deselect SO 1. See Table 11 on ...
Page 12
Figure 7. Write mode waveforms OE WE CEI D Table 3. AC electrical characteristics (M41T315Y) Symbol Parameter t t READ cycle time AVAV CEI access time ELQV access time GLQV ...
Page 13
... Table 4. AC electrical characteristics (M41T315V/W) Symbol Parameter t t READ cycle time AVAV CEI access time ELQV access time GLQV CEI to output low Z ELQX COE output low Z GLQX OEE t t CEI to output high Z EHQZ output high Z ...
Page 14
Figure 8. Comparison register definition 7 BYTE 0 1 BYTE 1 0 BYTE BYTE 3 BYTE 4 1 BYTE 5 0 BYTE 6 1 BYTE 7 0 Note: Pattern recognition in “hex” is C5, 3A, A3, 5C, ...
Page 15
The data retention current value of the SRAMs can then be added to the IBAT value of the M41T315Y/V/W to determine the total current requirements for data retention. The available battery capacity for the SNAPHAT current to determine the ...
Page 16
Clock operation 3.1 Clock register information Clock information is contained in eight registers of 8 bits, each of which is sequentially accessed 1 bit at a time after the 64-bit pattern recognition sequence has been completed. When updating the ...
Page 17
Table 5. RTC register map Register 0.1 seconds seconds minutes 10/ 3 12/ OSC years Keys: A/P ...
Page 18
... Negative undershoots below –0.3V are not allowed on any pin while in the Battery Back-up mode. Caution: Do NOT wave solder SOIC to avoid damaging SNAPHAT sockets. 18/30 Parameter SNAPHAT , oscillator off) CC SOIC M41T315Y M41T315V/W Value Unit C –40 to +85 ° ® C –40 to +85 ° C –55 to +125 ° ...
Page 19
... Parameter V supply voltage CC Ambient operating temperature Load capacitance (C Input rise and fall times Input pulse voltages Input and output timing ref. voltages Figure 10. AC testing load circuit Note: 50pF for M41T315V. Table 8. Capacitance Symbol C Input capacitance IN (3) C Input/output capacitance IO 1. Effective capacitance measured with power supply at 5V; sampled only; not 100% tested. ...
Page 20
... CEI = V IH – 0.2 CC1 –0.3 2 –1.0 mA 2.4 4.25 V BAT 2.5 V – 0.2 CC1 or V – 0.2 BAT = 3.0V BAT 25° – 0.2V BAT . CCI 19. M41T315V/W –85 Max Min Typ Max ±1 ±1 ±1 ± 150 100 0.8 –0.3 0 0.3 2.0 CC1 0.3 0.4 0.4 2.4 2.80 (V) 2.97 (V) 4.50 2.60 (W) 2.70 (W) 2 ...
Page 21
... Input pulse rise and fall times equal 10ns Min Typ 32.768 12.5 tFB tF tPF DON’T CARE V BAT 0.2V V BAT (1)(2) Min 1.5 fall time 300 CC fall time 10 rise time M41T315Y M41T315V/W 19. Max Unit kHz 60 kΩ tREC 0.2V tPD AI04257 Max Unit 2.5 ms µs µs µs µ ...
Page 22
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 ...
Page 23
Figure 12. SO16 - 16-lead plastic small outline, package outline SO-b Note: Drawing is not to scale Table 12. SO16 - 16-lead plastic small outline (150 mils body width), package mechanical data Sym Typ ...
Page 24
Figure 13. SOH28 - 28-lead plastic small outline, package outline Note: Drawing is not to scale. Table 13. SOH28 - 28-lead plastic small outline, package mechanical data Sym Typ 1. ...
Page 25
Figure 14 4-pin SNAPHAT housing for 48mAh battery and crystal, package mechanical data eA D Table 14 4-pin SNAPHAT housing for 48mAh battery and crystal, package mechanical data mm Sym Typ Min A A1 6.73 A2 ...
Page 26
Figure 15 4-pin SNAPHAT housing for 120mAh battery and crystal, package outline Table 15 4-pin SNAPHAT housing for 120mAh battery and crystal, package mechanical data Sym Typ ...
Page 27
Part numbering Table 16. Ordering information scheme Example: Device type M41T Supply voltage and write protect voltage (1) 315Y = V = 4.5 to 5.5V 4.25 to 4.50V CC PFD 315V = V = 3.0 to 3.6V; ...
Page 28
Caution: Do not place the SNAPHAT battery package “M4TXX-BR12SH” in conductive foam as it will drain the lithium button-cell battery. For other options, or for more information on any aspect of this device, please contact the ST sales office nearest ...
Page 29
Revision history Table 18. Document revision history Date Revision Jun-2001 17-Jul-2001 18-Sep-2001 27-Sep-2001 01-May-2002 04-Nov-2002 26-Mar-2003 08-Jun-2004 26-Nov-2007 1.0 First issue 1.1 Basic formatting changes 1.2 Changed pin 8 in 28-pin to V 1.3 Added ambient temp to DC ...
Page 30
... 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. ...