DS1672 Maxim, DS1672 Datasheet
DS1672
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DS1672 Summary of contents
Page 1
... GENERAL DESCRIPTION The DS1672 incorporates a 32-bit counter and power-monitoring functions. The 32-bit counter is designed to count seconds and can be used to derive time-of-day, week, month, month, and year by using a software algorithm. A precision, temperature-compensated comparator circuit monitors the status of V When an out-of-tolerance condition occurs, an internal power-fail signal is generated that forces the reset to the active state ...
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... DS1672U-2+ -40°C to +85°C DS1672U-3+ -40°C to +85°C DS1672U-33+ -40°C to +85°C DS1672U-33+T&R -40°C to +85°C + Denotes a lead-free/RoHS-compliant device “+” anywhere on the top mark denotes a lead-free device 2-digit alphanumeric revision code. VOLTAGE (V) PIN-PACKAGE 2.0 8 PDIP (300 mils) 3 ...
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... Standby Current (Note 3) Power-Fail Voltage V Leakage Current I BACKUP BACKUPLKG Logic 0 Output (Note 4) Logic 0 Output (Note 4, DS1672-2 Only) Note 1: All voltages referenced to ground. Note 2: I specified with SCL clocking at max frequency (400kHz), trickle charger disabled. CCA Note 3: I specified with CCS CC CCTYP Note 4: SDA and RST ...
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... RF generating signals. Refer to Application Note 58: Crystal Considerations for Dallas Real-Time Clocks for additional specifications SYMBOL MIN TYP I 0.425 BACKUPOSC I BACKUP * SYMBOL MIN TYP f 32.768 O ESR DS1672 MAX UNITS µA 1 200 nA MAX UNITS kHz kΩ ...
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... SCL signal) in IHMIN ) of the SCL signal. LOW ≥ to 250ns must then be met. This will SU:DAT = 1000 + 250 = 1250ns before the SCL SU:DAT DS1672 ...
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... RPU t 300 equal to 250ms plus the startup time of the crystal oscillator. RPU HD:STA t SU:STA t t HIGH SU:DAT REPEATED START t RPD DON'T CARE HIGH IMPEDANCE TYP MAX UNITS 10 µs 250 ms µs µs t SU:STO RPU RECOGNIZED VALID DS1672 ...
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... X1, X2 crystal layout considerations, refer to Application Note 58: Crystal Considerations with Dallas Real-Time Clocks. The DS1672 can also be driven by an external 32.768kHz oscillator. In this configuration, the X1 pin is connected to the external oscillator signal and the X2 pin is left unconnected Battery Input for Any Standard 3V Lithium Cell or Other Energy Source. ...
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... V to stabilize. RPU CC The block diagram in Figure 4 shows the main elements of the DS1672. As shown, communications to and from the DS1672 occur serially over the I C bus. Access is obtained by implementing a START condition and providing a device identification code followed by a register address. Subsequent registers can be accessed sequentially until a STOP condition is executed ...
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... Note 5: “Crystal Considerations with Dallas Real-Time Clocks” for detailed information. Address Map The counter is accessed by reading or writing the first 4 bytes of the DS1672 (00h–03h). The control register and trickle charger are accessed by reading or writing the appropriate register bytes as illustrated in Table 2. If the master continues to send or request more data after the address pointer has reached 05h, the address pointer will wrap around to location 00h ...
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... In order to prevent accidental enabling, only a pattern on 1010 will enable the trickle charger. All other patterns will disable the trickle charger. The DS1672 powers up with the trickle charger disabled. The diode select (DS) bits (bits 2, 3) select whether or not a diode is ...
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... START and STOP conditions. The DS1672 operates as a slave on the I are made via the open-drain I/O lines SDA and SCL. Within the bus specifications, a standard mode (100kHz maximum clock rate) and a fast mode (400kHz maximum clock rate) are defined. The DS1672 operates in both modes. ...
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... SDA line. After the DS1672 acknowledges the slave address + write bit, the master transmits a word address to the DS1672. This will set the register pointer on the DS1672, with the DS1672 acknowledging the transfer. The master may then transmit zero or more bytes of data, ...
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... However, in this mode, the direction bit will indicate that the transfer direction is reversed. Serial data is transmitted on SDA by the DS1672 while the serial clock is input on SCL. START and STOP conditions are recognized as the beginning and end of a serial transfer (Figure 8). ...
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... PDIP (300 mils (150 mils) 8 µSOP (3mm) <Data(n+1) <Data(n+2)> A XXXXXXXX A XXXXXXXX A XXXXXXXX A P DATA TRANSFERRED (X+1 BYTES + ACKNOWLEDGE); NOTE: LAST DATA BYTE IS FOLLOWED BY A NOT ACKNOWLEDGE (A) SIGNAL) THETA-JC 40°C/W 36°C/W 42°C/W OUTLINE NO. P8+1 21-0043 S8+5 21-0041 U8+1 21-0036 <Data(n+X)> LAND PATTERN NO. — 90-0096 90-0092 DS1672 ...
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... © 2011 Maxim Integrated Products DESCRIPTION Maxim is a registered trademark of Maxim Integrated Products, Inc. DS1672 PAGES CHANGED 10, 15 ...