DS1344 Maxim, DS1344 Datasheet
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DS1344
Related parts for DS1344
DS1344 Summary of contents
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... Rev 1; 12/11 General Description The DS1343/DS1344 low-current real-time clocks (RTCs) are timekeeping devices that provide an extremely low standby current, permitting longer life from a backup supply source. The devices also support high-ESR crystals, broadening the pool of usable crystals for the devices. The clock/calendar provides seconds, minutes, hours, day, date, month, and year information ...
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... Power-Supply Active Current Power-Supply Standby Current (Note 5) Backup Leakage Current I BATLKG Backup Current (Oscillator Off) DS1343 Backup Current (Note 6) DS1344 2 Junction Temperature Maximum .....................................+150NC Storage Temperature Range ............................ -55NC to +125NC Lead Temperature (soldering, 10s) ................................+260NC + 0.3V) Soldering Temperature (reflow) ......................................+260NC CC TDFN ) ..........91NC/W Junction-to-Ambient Thermal Resistance ( ...
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... DC_ELECTRICAL_CHARACTERISTICS_(continued +5.5V +1.3V to +5.5V CC(MIN) BAT PARAMETER SYMBOL DS1343 Backup Current (Note 7) DS1344 Input Leakage (CE, SERMODE, SCLK, SDI) Output Leakage (INT0, INT1, PF, SDO) Output Logic 1 (PF, SDO) Output Logic 0.4V OL (INT0, INT1, PF, SDO) Power-Fail Trip Point Switchover Voltage Trickle-Charger Resistors AC_ELECTRICAL_CHARACTERISTICS ...
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... OSF Note_10: Guaranteed by design; not 100% production tested. 4 CONDITIONS t REC VCCF VCCR CONDITIONS C (Note 10 (Note 10) O CONDITIONS f O ESR DS1343 C L DS1344 = 0mA, trickle charger disabled. OUT MIN TYP MAX UNITS 150 MIN TYP MAX UNITS ...
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SCLK* t CDH t DC SDI R WRITE ADDRESS BYTE *SCLK CAN BE EITHER POLARITY. TIMING SHOWN FOR CPOL = 1. SERMODE = SCLK* t CDH t ...
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Low-Current SPI/3-Wire RTCs SCLK t CDH I/O* *I/O IS SDI AND SDO CONNECTED TOGETHER. SERMODE = GND SCLK t CDH I/O* *I/O IS SDI AND SDO CONNECTED TOGETHER. ...
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... -40°C A 3.5 4.0 4.5 5.0 5.5 SUPPLY VOLTAGE (V) DS1343 BATTERY CURRENT2 vs. BATTERY VOLTAGE EGFIL = 1 DOSF = 0mA OUT T = +85° +25° -40°C A 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 BATTERY VOLTAGE (V) DS1344 BATTERY CURRENT2 vs. BATTERY VOLTAGE EGFIL = 1, DOSF = 0mA OUT T = +85° +25° -40°C A 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 BATTERY VOLTAGE (V) 7 ...
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... INT1 operates when the component is powered by V drain output and requires an external pullup resistor. Pin Configurations DS1343 DS1344 TDFN (3mm × 3mm) ...
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... CC Power-Supply Input Exposed Pad (TDFN Only). Connect to GND or leave unconnected. 32.768kHz X1 X2 OSCILLATOR AND COUNTDOWN CHAIN CLOCK, CALENDAR, AND ALARM REGISTERS DS1343 CONTROL DS1344 REGISTERS INPUT SHIFT USER RAM REGISTER , SPI communication is selected the PF pin is driven low. PF Functional Diagram 1Hz INT0 ...
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... Low-Current SPI/3-Wire RTCs Detailed Description The DS1343/DS1344 low-current real-time clocks (RTCs) are timekeeping devices that consume an extremely low timekeeping current and also support high-ESR crystals, broadening the pool of usable crystals for the device. The devices provide a full binary-coded decimal (BCD) clock calendar that is accessed by a simple serial inter- face ...
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LOCAL GROUND PLANE (LAYER 2) NOTE: AVOID ROUTING SIGNAL LINES IN THE CROSSHATCHED AREA (UPPER LEFT QUADRANT) OF THE PACKAGE UNLESS THERE IS A GROUND PLANE BETWEEN THE SIGNAL LINE AND THE DEVICE PACKAGE. Figure 1. Layout Example Register Map ...
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Low-Current SPI/3-Wire RTCs Table_1._Register_Map BIT_7_ ADDRESS BIT_6 MSB 00h 0 10 Seconds 01h 0 10 Minutes 02h 0 12/24 03h 0 0 04h 0 0 05h Century 0 06h 10 Year 07h A0M1 10 Seconds 08h A0M2 10 Minutes 09h ...
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BIT_7 BIT_6 BIT_5 X DOSF EOSC EOSC: Enable oscillator. During battery backup, when EOSC is set to 0, the oscillator is enabled during back- BIT 7 up operation. When set to 1, the oscillator is stopped when ...
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... V select the resistor and diodes, as shown in Table 3. The user determines diode and resistor selection according to the maximum current desired for secondary battery or super cap charging. The maximum charging current can be calculated using the equation that follows. Status Register (10h) ...
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... Assume, for the purposes of the example, that a system power supply applied connected Also assume that the trickle charger BAT has been enabled with one diode and resistor R1. The maximum current I would be calculated as follows: MAX I = (5.0V - diode drop)/R1 ≈ (5.0V - 0.6V)/2kΩ ≈ MAX 2.2mA ...
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Low-Current SPI/3-Wire RTCs Serial Peripheral Interface (SPI) The serial peripheral interface (SPI synchronous bus for address and data transfer, and is used when interfacing with the SPI bus on specific Motorola micro- controllers, such as the 68HC05C4 and ...
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CE SCLK SDI R/W SDO *SCLK CAN BE EITHER POLARITY. SERMODE = Figure 4. SPI Single-Byte Write CE SCLK SDI R/W HIGH-Z SDO *SCLK CAN BE EITHER POLARITY. SERMODE = V ...
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... The INT0 and INT1 outputs are open drain and therefore require external pullup resistors to realize a logic-high output level. The devices contain Maxim’s redundant battery-charge protection circuit to prevent any charging of an external battery. The DS1343 and DS1344 are recognized by Underwriters Laboratories (UL) under file E141114 ...
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... DS1344E-18+* -40NC to +85NC DS1344E-3+* -40NC to +85NC DS1344E-33+ -40NC to +85NC DS1344D-18+* -40NC to +85NC DS1344D-3+* -40NC to +85NC DS1344D-33+ -40NC to +85NC +Denotes a lead(Pb)-free/RoHS-compliant package. *Future product—Contact factory for availability. **EP = Exposed pad. Chip Information SUBSTRATE CONNECTED TO GROUND Low-Current SPI/3-Wire RTCs ...
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... REVISION REVISION NUMBER DATE 0 3/11 Initial release Removed future status from several DS1344 parts in the Ordering Information table; added UL recognized to the Features and Battery Charge Protection sections; 1 12/11 added I BATLKG section; added DS1344 Typical Operating Characteristics graphs Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. ...