DS32B35 Maxim Integrated Products, DS32B35 Datasheet
DS32B35
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DS32B35 Summary of contents
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... C serial interface, ♦ Nonvolatile Memory with 10 Years of Guaranteed Backup Time and Write Protection ♦ Two Available Densities of Nonvolatile Memory 2048 Bytes (DS32B35) 8192 Bytes (DS32C35) ♦ No Cycle Limitations on Memory ♦ Power-Switching Circuit Selects Between Main Power and Battery Backup for the RTC ♦ ...
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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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Accurate I 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 ...
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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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Accurate I 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 PF(MAX) Recovery at ...
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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 t 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 RST ACTIVE 100 50 0 2.0 3.0 4.0 V (V) CC SUPPLY CURRENT vs. TEMPERATURE 1.000 BSY = 0, SDA ...
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Accurate I C RTC with Integrated TCXO/Crystal/FRAM DS32x35 X1 OSCILLATOR AND CAPACITOR ARRAY X2 WP SCL FRAM BAT POWER CONTROL GND SCL INTERFACE AND ADDRESS REGISTER DECODE SDA 8 _____________________________________________________________________ PUSHBUTTON RESET; CONTROL ...
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Accurate I PIN NAME Write Protect. When WP is high, the entire FRAM memory array is write protected. When WP is low, all 1 WP addresses can be written. This pin is internally pulled down. 2, N.C. No Connection. Must ...
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Accurate I C RTC with Integrated TCXO/Crystal/FRAM The Block Diagram shows the main elements of the DS32x35. The nine blocks can be grouped into six functional groups: TCXO, power control, pushbutton 2 function, RTC interface, and FRAM. ...
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... DS32x35. See the I C Serial Data Bus section for details. Table 2. Memory Slave Address DEVICE SLAVE ADDRESS 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 ...
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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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Accurate I The DS32x35 contains 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 ...
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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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Accurate I BIT 7 BIT 6 BIT 5 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 ...
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... BIT 5 BIT 4 BIT BIT 2 BIT 1 Data Data BIT 2 BIT FRAM Address Map DS32B35 FRAM Register Map BIT 2 BIT 1 BIT 0 RANGE DS32C35 FRAM Register Map BIT 2 BIT 1 BIT 0 RANGE ...
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Accurate I SDA t BUF t LOW SCL t HD:STA STOP START 2 Figure 1. Data Transfer Serial Bus SDA MSB SLAVE ADDRESS SCL 1 2 START CONDITION 2 Figure Data Transfer Overview 2 ...
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... START condition. The slave address byte contains one of the 7-bit DS32x35 addresses. The slave address is 1101000 for the 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). ...
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... START condition. The slave address byte contains one of the 7-bit DS32x35 addresses. The slave address is 1101000 for the RTC. For the DS32B35 FRAM, the first four bits are 1010, and the next three bits select one of eight blocks of data <SLAVE ADDRESS> <R/W> ...
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... A XXXXXXXX START MASTER TO SLAVE A - ACKNOWLEDGE P - STOP A - NOT ACKNOWLEDGE R/W - READ/WRITE OR DIRECTION BIT ADDRESS = D1H 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 < ...
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... PACKAGE 20-pin SO (300 mils) Rev 0; 12/06: Initial data sheet release registered trademark of Maxim Integrated Products, Inc. Ordering Information TOP PIN-PACKAGE MARK 20 SO DS32B35 20 SO DS32B35 20 SO DS32C35 20 SO DS32B35 Chip Information Thermal Information Package Information DOCUMENT NO. 56-G4009-001 Revision History † ...