DS32C35 Maxim Integrated Products, Inc., DS32C35 Datasheet
DS32C35
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DS32C35 Summary of contents
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... The date at the end of the month is automatically adjusted for months with fewer than 31 days, including corrections for leap year. The DS32B35/DS32C35 include a bank of nonvolatile memory that does not require a backup energy source to maintain memory contents. In addition, there are no read or write cycle limitations ...
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Accurate I C RTC with Integrated TCXO/Crystal/FRAM ABSOLUTE MAXIMUM RATINGS Voltage Range on Any Pin Relative to Ground......-0.3V to +5.0V Operating Temperature Range ..........................-40°C to +85°C Junction Temperature ......................................................+125°C Storage Temperature Range ...............................-40°C to +85°C Stresses beyond those listed ...
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ELECTRICAL CHARACTERISTICS (continued) = 2.7V to 3.63V -40°C to +85°C, unless otherwise noted.) (Note PARAMETER SYMBOL V Leakage Current BAT I BATLKG (V Active) CC Output Frequency Frequency Stability vs. Temperature Frequency Stability vs. ...
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Accurate I C RTC with Integrated TCXO/Crystal/FRAM AC ELECTRICAL CHARACTERISTICS (V = 2.7V to 3.63V -40°C to +85°C, unless otherwise noted.) (Note PARAMETER SYMBOL SCL Clock Frequency Bus Free Time Between STOP and START ...
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POWER-SWITCH CHARACTERISTICS (T = -40°C to +85°C, Note 1, see the Power-Switch Timing diagram.) A PARAMETER SYMBOL V Fall Time PF(MAX) V PF(MIN) V Rise Time PF(MIN) V PF(MAX) Recovery at Power-Up WARNING: Negative ...
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Accurate I C RTC with Integrated TCXO/Crystal/FRAM RST PF(MAX PF(MIN) t VCCF RST 6 _____________________________________________________________________ Pushbutton Reset Timing RST Power-Switch Timing VCCR t REC ...
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Accurate +3.3V +25°C, unless otherwise noted STANDBY SUPPLY CURRENT vs. SUPPLY VOLTAGE 150 125 RST ACTIVE 100 2.0 2.5 3.0 3.5 4.0 V (V) CC SUPPLY CURRENT vs. TEMPERATURE ...
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... Accurate I C RTC with Integrated TCXO/Crystal/FRAM DS32B35/DS32C35 X1 OSCILLATOR AND CAPACITOR ARRAY X2 WP SCL FRAM BAT POWER CONTROL GND SCL INTERFACE AND ADDRESS REGISTER DECODE SDA 8 _____________________________________________________________________ PUSHBUTTON RESET; CONTROL LOGIC/ SQUARE-WAVE BUFFER; DIVIDER INT/SQW CONTROL CONTROL AND STATUS TEMPERATURE ...
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... The devices are available in both commercial and industrial temperature ranges and is offered in a 300-mil, 20-pin SO package. The DS32B35/DS32C35 include a bank of nonvolatile memory that do not require a backup energy source to maintain the memory contents. In addition, there are no 2 ...
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... Accurate I C RTC with Integrated TCXO/Crystal/FRAM The Block Diagram shows the main elements of the DS32B35/DS32C35. The nine blocks can be grouped into six functional groups: TCXO, power control, pushbut- 2 ton function, RTC interface, and FRAM. Their opera- tions are described separately in the following sections. ...
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... See the I C Serial Data Bus section for details. Table 2. Memory Slave Address DEVICE DS32B35 DS32C35 R = Read/write select bit Warning: The FRAM does not inhibit reads or writes when V is below the minimum operating voltage. CC FRAM reads are destructive, that is, when a read is performed, the device internally writes the memory back to the original value ...
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Accurate I C RTC with Integrated TCXO/Crystal/FRAM Table 3. RTC Register Map BIT 7 ADDRESS BIT 6 BIT 5 (MSB) 00h 0 10 Seconds 01h 0 10 Minutes AM/PM 02h 0 12/24 10 Hour 03h 04h ...
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... The DS32B35/DS32C35 contain two time-of-day/date alarms. Alarm 1 can be set by writing to registers 07h to 0Ah. Alarm 2 can be set by writing to registers 0Bh to 0Dh. The alarms can be programmed (by the alarm enable and INTCN bits of the Control register) to acti- vate the INT/SQW output on an alarm match condition. ...
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Accurate I C RTC with Integrated TCXO/Crystal/FRAM BIT 7 BIT 6 BIT 5 EOSC BBSQW CONV Special-Purpose Registers Control Register (0Eh) Bit 7: Enable Oscillator (EOSC). When set to logic 0, the oscillator is started. When set to logic ...
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BIT 7 BIT 6 OSF 0 Status Register (0Fh) Bit 7: Oscillator Stop Flag (OSF). A logic 1 in this bit indicates that the oscillator either is stopped or was stopped for some period and may be used to judge ...
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... BIT 2 BIT 1 Data Data BIT 2 BIT FRAM Address Map DS32B35 FRAM Register Map BIT 2 BIT 1 BIT 0 RANGE 00– 00–FF DS32C35 FRAM Register Map BIT 2 BIT 1 BIT 0 RANGE BIT 0 Data BIT 00–FF : 00–FF ...
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... C bus and a fast mode (400kHz maximum clock rate) are defined. The DS32B35/DS32C35 work in both modes. The following bus protocol has been defined (Figure 2): • Data transfer can be initiated only when the bus is not busy. ...
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... RTC. For the DS32B35 FRAM, the first four bits are 1010, and the next three bits select one of eight blocks of data (see Table 2). For the DS32C35 FRAM, the first seven bits are 1010000. Each slave address is followed by the direction bit (R/W), which is zero for a write ...
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... Accurate I 2) Slave transmitter mode (DS32B35/DS32C35 read mode): The first byte is received and handled as in the slave receiver mode. However, in this mode, the direction bit indicates that the transfer direction is reversed. The device transmits serial data on SDA while the serial clock is input on SCL. START and STOP conditions are recognized as the beginning and end of a serial transfer (see Figure 4) ...
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... Figure 6. Data Read—DS32B35 FRAM Slave Transmitter Mode <SLAVE ADDRESS> <R/W> S 1010000 0 A XXXA S - START MASTER TO SLAVE A - ACKNOWLEDGE P - STOP R/W - READ/WRITE BIT Figure 7. Data Write—DS32C35 FRAM Slave Receiver Mode <SLAVE ADDRESS> <R/W> <DATA (n)> S 1010000 START MASTER TO SLAVE A - ACKNOWLEDGE P - STOP A - NOT ACKNOWLEDGE R/W - READ/WRITE OR DIRECTION BIT ADDRESS = D1H Figure 8. Data Read— ...
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... For the latest package outline information www.maxim-ic.com/DallasPackInfo. PACKAGE TYPE 20 SO (300 mils) ____________________________________________________________________ Typical Operating Circuit 32kHz V BAT GND N.C. N.C. N.C. N.C. Selector Guide FRAM DENSITY MARK DS32B35 DS32B35 DS32C35 DS32C35 Thermal Information Package Information PACKAGE CODE DOCUMENT NO. — 56-G4009-001 † TOP 21 ...
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... REVISION NUMBER DATE 0 12/06 Initial release. Changed data sheet title/references to DS32x35 with DS32B35/DS32C35. 1 1/08 Added text to the General Description section about the clock/date operation. In Table 3, changed 04h range from 00–31 to 01–31. Updated the RTC descriptions in the General Description and Detailed Description sections. ...