DS1682 Maxim, DS1682 Datasheet
DS1682
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DS1682 Summary of contents
Page 1
... RC time base that eliminates the need for an external crystal. Using EEPROM technology to maintain data in the absence of power, the DS1682 requires no backup power source. The DS1682 detects and records the number of events on the EVENT pin and the total cumulative event time since the DS1682 was last reset to 0 ...
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... PIN DESCRIPTION PIN NAME Event Input. The EVENT pin is the input the DS1682 monitors to determine when an event occurs. When the pin is pulled high, the contents of the EEPROM are transferred to the ETC and the oscillator starts. The ETC begins to count in quarter- second increments. When the EVENT pin falls to logic 0, the event counter ...
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... The user memory can be separately write-protected. User-modified data is not stored in EEPROM until an event becomes inactive. Figure 2 shows the DS1682 measuring total run time and operating from a battery with the alarm tied to an LED and a pushbutton switch to trigger the alarm output. Figure 2. Total Run Time Figure 3 shows the DS1682 in a total time-of-use application where power may be removed at the same time as the end of the event ...
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... CC EEPROM write time. This assumes that the V 2.5V on the DS1682 is at least t Figure 4 shows the DS1682 in a total time-of-use application with power that can be removed at the same time as the end of the event. In this application, the The external RST IC ends the event as V ...
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Table 1. Memory Map ADDR BIT 7 BIT ...
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... Figure 5. Event Input Timing DEVICE SETUP Once installed in a system, the DS1682 can be programmed to record events as required by the application, and can be tested by generating events and monitoring the results. Afterwards, it can be “locked” to prevent alteration of the event and alarm registers and the alarm condition. ...
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... The alarm register is a 32-bit register that holds time in quarter-second resolution. When a nonzero number is programmed into the alarm register, the ALARM function is enabled and the DS1682 monitors the values in the ETC for the programmed value in the alarm register. When the ETC matches the alarm value, the alarm flag is set ...
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... WMDF is set the 10-byte user memory becomes read-only. This bit is read-only. The writes need not be consecutive. Cycling power on V Bit 3: Alarm Output Select (AOS). If AOS is 0 and AF is true, the DS1682 activates the ALARM output during an event when AF becomes true. The DS1682 also activates the ALARM output by pulling the pin low four times at power-up, at the start and end of an event, or when the ALARM pin is pulled low and released ...
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... A master device that generates the serial clock (SCL), controls the bus access, and generates the START and STOP conditions must control the bus. The DS1682 operates as a slave on the 2-wire bus. Connections to the bus are made through the open-drain I/O lines SDA and SCL. ...
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In this case, the slave must leave the data line high to enable the master to generate the STOP condition. Depending upon the state ...
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... However, in this mode, the direction bit indicates that the transfer direction is reversed. Serial data is transmitted on SDA by the DS1682 while the serial clock is input on SCL. The slave address byte is the first byte received after the master generates a START condition. The address byte contains the 7-bit DS1682 address, followed by the direction bit (R/W) ...
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... Soldering Temperature………………………………………….See IPC/JEDEC J-STD-020 Specification This is a stress rating only and functional operation of the device at these or any other conditions beyond those indicated in the operation sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods of time can affect device reliability. ...
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AC ELECTRICAL CHARACTERISTICS (V = 2.5V to 5.5V -40°C to +85°C PARAMETER EEPROM Endurance EEPROM Write Time EEPROM Transfer to RAM ALARM Output Active- Low Pulse Width ALARM Output Active- High Pulse Width ALARM Input Pulled ...
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... EEPROM. EW has only to be met if the device does not stretch the low period (t DOCUMENT NO. 21-0041 © 2005 Maxim Integrated Products DS1682 Total-Elapsed-Time Recorder with Alarm minimum, including transients, during CC LOW ≥ 250ns must SU:DAT . If such a device does ...