isl12022m Intersil Corporation, isl12022m Datasheet
isl12022m
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isl12022m Summary of contents
Page 1
... Low Power RTC with Battery Backed SRAM, Integrated ±5ppm Temperature Compensation, and Auto Daylight Saving The ISL12022M device is a low power real time clock (RTC) with an embedded temperature sensor and crystal. Device functions include oscillator compensation, clock/calendar, power fail and low battery monitors, brownout indicator, one-time, periodic or polled alarms, intelligent battery backup switching, Battery Reseal™ ...
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... IRQ/F Interrupt Output/Frequency Output. Multi-functional pin that can be used as interrupt or frequency output pin. The OUT function is set via the configuration register. The output is open drain and requires a pull-up resistor Power Supply ISL12022M V RANGE TEMP RANGE DD (V) 2.7 to 5.5 - ...
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... See Tech Brief TB379 for details The ISL12022M Oscillator Initial Accuracy can change after solder reflow attachment. The amount of change will depend on the reflow temperature and length of exposure. A general rule is to use only one reflow cycle and keep the temperature and time as short as possible. ...
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... START Condition Setup Time SU:STA t START Condition Hold Time HD:STA t Input Data Setup Time SU:DAT t Input Data Hold Time HD:DAT 4 ISL12022M = +2.7 to +5.5V, Temperature = -40°C to +85°C, unless otherwise stated. DD MIN CONDITIONS (Note 10) = +2.7 to +5.5V, Temperature = -40°C to +85°C, DD MIN TEST CONDITIONS (Note 10) -0.3 ...
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... C specific parameters and are not tested, however, they are used to set conditions for testing devices to validate specification. 10. Parameters with MIN and/or MAX limits are 100% tested at +25°C, unless otherwise specified. Temperature limits established by characterization and are not production tested. 5 ISL12022M = +2.7 to +5.5V, Temperature = -40°C to +85°C, DD TEST CONDITIONS (Note 10) ...
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... SDA (INPUT TIMING) SDA (OUTPUT TIMING) EQUIVALENT AC OUTPUT LOAD CIRCUIT FOR V 5.0V 1533Ω SDA AND IRQ/F OUT 100pF FIGURE 1. STANDARD OUTPUT LOAD FOR TESTING THE DEVICE WITH ISL12022M t t HIGH LOW t SU:DAT t HD:DAT Symbol Table WAVEFORM = 5V DD FOR V = 0.4V OL AND I ...
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... TEMPERATURE (°C) FIGURE TEMPERATURE DD1 5.5V BAT 3. -40 - TEMPERATURE (°C) FIGURE 6. OSCILLATOR ERROR vs TEMPERATURE 7 ISL12022M Temperature is +25°C unless otherwise specified. 1600 1400 1200 1000 800 600 4.3 4.8 5.3 (V =0V) DD 4.4 4.2 4.0 3.8 3 2.7V DD 3.4 3.2 3 2.7V DD ...
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... FIGURE 10. I WITH TSE = 1 vs TEMPERATURE DD General Description The ISL12022M device is a low power real time clock (RTC) with embedded temperature sensor and crystal. It contains crystal frequency compensation circuitry over the operating temperature range good to ±5ppm accuracy. It also contains a clock/calendar with Daylight Savings Time (DST) adjustment, ...
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... These power control situations are illustrated in Figures 12 and 13. The I power consumption. Aside from this, all RTC functions are operational during battery backup mode. Except for SCL and SDA, all the inputs and outputs of the ISL12022M are active during battery backup mode unless disabled via the control register pin is activated ...
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... FOBATB bit. For more information on the alarm, please see “ALARM Registers (10h to 15h)” on page 18. Frequency Output Mode The ISL12022M has the option to provide a clock output signal using the IRQ/F frequency output mode is set by using the FO bits to select 15 possible output frequency values from 1/32Hz to 32kHz. ...
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... Oscillator Compensation The ISL12022M provides both initial timing correction and temperature correction due to variation of the crystal oscillator. Analog and digital trimming control is provided for initial adjustment, and a temperature compensation function is provided to automatically correct for temperature drift of the crystal. Initial values for the initial AT and DT settings ...
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... DstDtFd D 23h DstHrFd D DSTCR 24h DstMoRv D 25h DstDwRv D 26h DstDtRv D 27h DstHrRv D 28h TK0L TK07 TEMP 29h TK0M 0 12 ISL12022M BIT OSCF DSTADJ ALM LVDD WRTC IM FOBATB FO3 RESEALB VB85Tp2 VB85Tp1 VB85Tp0 IDTR00 IATR05 IATR04 IATR03 ALPHA6 ...
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... This means that the year 2000 is a leap year and the year 2100 is not. The ISL12022M does not correct for the leap year in the year 2100. Control and Status Registers (CSR) Addresses [07h to 0Fh] ...
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... VB75Tp0 in the PWR_VBAT registers. REAL TIME CLOCK FAIL BIT (RTCF) This bit is set to a “1” after a total power failure. This is a read only bit that is set by hardware (ISL12022M internally) when the device powers up after having lost all power (defined and V = 0V) ...
Page 15
... Three bits select the first alarm (85% of Nominal V the battery voltage monitor. There are total of 7 levels that could 15 ISL12022M be selected for the first alarm. Any of the of levels could be selected as the first alarm with no reference as to nominal Battery voltage level. See Table 8. ...
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... IATR control. See Table 10. The IDTR0 register should only be changed while the TSE (Temp Sense Enable) bit is “0”. The ISL12022M has a preset Initial Digital Trimming value corresponding to the crystal in the module. This value is recalled on initial power-up and is READ-ONLY. It cannot be overwritten by the user ...
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... T0, or the ALPHA Cold (there is an Alpha Hot register that must be programmed as well normally given in units of ppm/°C value of -0.034. The ISL12022M device uses a scaled version of the absolute value of this coefficient in order to get an integer value. Therefore, ALPHA <7:0> is defined as the (|Actual ALPHA Value| x 2048) and converted to binary ...
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... The BETA VALUES result is indexed in the right hand column and the resulting Beta factor (for the register the same row in the left column. The ISL12022M has a preset BETA value corresponding to the crystal in the module. This value is recalled on initial power-up and is preset in device production READ ONLY and cannot be overwritten by the user ...
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... ALM bit in the status register to “1” and also bringing the IRQ/F low. 19 ISL12022M Example 2 • Pulsed interrupt once per minute (IM = ”1”) • Interrupts at one minute intervals when the seconds register seconds. ...
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... Day of the Week. DstDwFdE sets the priority of the Day/Week over the Date. For DstDwFdE = 1, Day/Week is the priority. You must have the correct Day of Week entered in the RTC registers for the Day/Week correction to work properly. 20 ISL12022M TABLE 20. DST FORWARD REGISTERS ...
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... XT0. Crystals normally have a turnover temperature between +20°C and +30°C, with most occurring near +25°C. (EQ. 3) ADDR 2Ch The ISL12022M has a preset Turnover temperature corresponding to the crystal in the module. This value is recalled on initial power-up and is preset in device production READ ONLY and cannot be overwritten 3 2 ...
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... Data states on the SDA line can change only during SCL 20.0 LOW periods. SDA state changes during SCL HIGH are 19.5 reserved for indicating START and STOP conditions (see 19.0 Figure 15). On power-up of the ISL12022M, the SDA pin is in the input mode. 18.5 2 All I C interface operations must begin with a START 18 ...
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... During the ninth clock cycle, the receiver pulls the SDA line LOW to acknowledge the reception of the eight bits of data (see Figure 16). The ISL12022M responds with an ACK after recognition of a START condition followed by a valid Identification Byte, and once again, after successful receipt of an Address Byte. The ISL12022M also responds with an ACK after receiving a Data Byte of a write operation ...
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... A Write operation requires a START condition, followed by a valid Identification Byte, a valid Address Byte, a Data Byte, and a STOP condition. After each of the three bytes, the ISL12022M responds with an ACK. At this time, the I interface enters a standby state. Read Operation A Read operation consists of a three byte instruction, followed by one or more Data Bytes (see Figure 20) ...
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... SRAM contents corruption and oscillator operation interruption. Layout Considerations The ISL12022M contains a quarts crystal and requires special handling during PC board assembly. Excessive shock and vibrations should be avoided, especially with automated handling equipment. Ultrasound cleaning is not advisable as it subjects the crystal to resonance and possible failure ...
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... This can be done for current year, and future years. Many regions have DST rules that use standard months, weeks and time of the day, which permit a pre-programmed, permanent setting. An example setup for the ISL12022M follows. TABLE 26. DST EXAMPLE VARIABLE VALUE ...
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... However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries. For information regarding Intersil Corporation and its products, see www.intersil.com 27 ISL12022M M20.3 (JEDEC MS-013-AC ISSUE C) 20 LEAD WIDE BODY SMALL OUTLINE PLASTIC PACKAGE ...