ds1305et-r Maxim Integrated Products, Inc., ds1305et-r Datasheet
ds1305et-r
Related parts for ds1305et-r
ds1305et-r Summary of contents
Page 1
FEATURES § Real-Time Clock (RTC) Counts Seconds, Minutes, Hours, Date of the Month, Month, Day of the Week, and Year with Leap-Year Compensation Valid Up to 2100 § 96-Byte, Battery-Backed NV RAM for Data Storage § Two Time-Of-Day Alarms, ...
Page 2
ORDERING INFORMATION PART TEMP RANGE DS1305 0°C to +70°C DS1305E+ 0°C to +70°C DS1305EN+ -40°C to +85°C DS1305EN+T&R -40°C to +85°C DS1305E+T&R 0°C to +70°C DS1305E 0°C to +70°C DS1305EN -40°C to +85°C DS1305EN/T&R -40°C to +85°C DS1305E/T&R 0°C to ...
Page 3
PIN DESCRIPTION PIN NAME DIP TSSOP CC2 BAT N.C. 13 INT0 7 9 INT1 8 10 GND 9 11 SERMODE 10 ...
Page 4
PIN DESCRIPTIONS (continued) PIN NAME DIP TSSOP 12 15 SDI 13 16 SDO CCIF CC1 OPERATION The block diagram in Figure 1 shows the main elements of the serial alarm RTC. ...
Page 5
RECOMMENDED LAYOUT FOR CRYSTAL Local ground plane (Layer 2) crystal CLOCK ACCURACY The accuracy of the clock is dependent upon the accuracy of the crystal and the accuracy of the match between the capacitive load of the oscillator circuit and ...
Page 6
Figure 2. RTC REGISTERS AND ADDRESS MAP HEX ADDRESS Bit7 READ WRITE 00H 80H 0 01H 81H 0 02H 82H 0 03H 83H 0 04H 84H 0 05H 85H 0 06H 86H — — 07H 87H M 08H 88H M ...
Page 7
During each clock update, the RTC compares the Alarm 0 and Alarm 1 registers with the corresponding clock registers. When a match occurs, the corresponding alarm flag bit in the status register is set the corresponding ...
Page 8
STATUS REGISTER (READ 10H) BIT7 BIT6 0 0 IRQF0 (Interrupt 0 Request Flag) – A logic 1 in the interrupt request flag bit indicates that the current time has matched the Alarm 0 registers. If the AIE0 bit is also ...
Page 9
Table 2. TRICKLE CHARGER RESISTOR AND DIODE SELECT TCS TCS TCS TCS Bit 7 Bit 6 Bit 5 Bit ...
Page 10
Figure 4. POWER SUPPLY CONFIGURATIONS NOTE: DEVICE IS WRITE-PROTECTED IF V NOTE: DEVICE DOES NOT PROVIDE AUTOMATIC WRITE PROTECTION. CONFIGURATION 1: BACKUP SUPPLY IS NONRECHARGEABLE LITHIUM BATTERY < CCTP CONFIGURATION 2: BACKUP SUPPLY IS A RECHARGEABLE BATTERY ...
Page 11
SERIAL INTERFACE The DS1305 offers the flexibility to choose between two serial interface modes. The DS1305 can communicate with the SPI interface or with a standard 3-wire interface. The interface method used is determined by the SERMODE pin. When this ...
Page 12
ADDRESS AND DATA BYTES Address and data bytes are shifted MSB first into the serial data input (SDI) and out of the serial data output (SDO). Any transfer requires the address of the byte to specify a write or read ...
Page 13
Figure 8. SPI MULTIPLE-BYTE BURST TRANSFER READING AND WRITING IN BURST MODE Burst mode is similar to a single-byte read or write, except that CE is kept high and additional SCLK cycles are sent until the end of the burst. ...
Page 14
INTERFACE The 3-wire interface mode operates similarly to the SPI mode. However, in 3-wire mode there is one I/O instead of separate data in and data out signals. The 3-wire interface consists of the I/O (SDI and SDO pins ...
Page 15
ABSOLUTE MAXIMUM RATINGS Voltage Range on Any Pin Relative to Ground……………………………………………..-0.5V to +7.0V Storage Temperature Range……………………………………………………………….-55°C to +125°C 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 ...
Page 16
DC ELECTRICAL CHARACTERISTICS (Over the operating range, unless otherwise specified.) PARAMETER Input Leakage Output Leakage I = 1.5mA Logic 0 OL Output I = 4.0mA -0.4mA Logic 1 OH Output I = -1.0mA OH V Active Supply ...
Page 17
AC ELECTRICAL CHARACTERISTICS (Over the operating range, unless otherwise specified.) (Figure 10 and Figure 11) PARAMETER Data to CLK Setup CLK to Data Hold CLK to Data Delay CLK Low Time CLK High Time CLK Frequency CLK Rise and ...
Page 18
Figure 10. TIMING DIAGRAM: 3-WIRE READ DATA TRANSFER * I/O IS SDI AND SDO TIED TOGETHER. Figure 11. TIMING DIAGRAM: 3-WIRE WRITE DATA TRANSFER * I/O IS SDI AND SDO TIED TOGETHER ...
Page 19
SPI AC ELECTRICAL CHARACTERISTICS (Over the operating range, unless otherwise specified.) (Figure 12 and Figure 13) PARAMETER Data to CLK Setup CLK to Data Hold CLK to Data Delay CLK Low Time CLK High Time CLK Frequency CLK Rise and ...
Page 20
Figure 12. TIMING DIAGRAM: SPI READ DATA TRANSFER * SCLK CAN BE EITHER POLARITY, TIMING SHOWN FOR CPOL = 1. Figure 13. TIMING DIAGRAM: SPI WRITE DATA TRANSFER * SCLK CAN BE EITHER POLARITY, TIMING SHOWN FOR CPOL = 1. ...
Page 21
... The Maxim logo is a registered trademark of Maxim Integrated Products, Inc. The Dallas logo is a registered trademark of Dallas Semiconductor Corporation. ...