RX8025SA EPSON Electronics, RX8025SA Datasheet
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RX8025SA
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RX8025SA Summary of contents
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RX-8025 SA/ C-Bus Interface Real-time Clock Module RX-8025 SA/NB Features built-in 32.768 kHz quartz oscillator, frequency adjusted for high precision 10 6 when Supports I C-Bus's high speed mode (400 kHz) ...
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RX-8025 SA/NB 3. Description of Pins 3.1. Pin Layout RX - 8025 SA 1. N.C. 2. SCL 3. FOUT 4. N.C. 5. TEST FOE SOP - 14pin 3.2. Pin Functions Signal name This ...
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RX-8025 SA/NB 4. Absolute Maximum Ratings Item Symbol Supply voltage V DD Input voltage Output voltage V O2 Storage temperature T STG 5. Operating Conditions Item Symbol Power voltage V DD Clock voltage V CLK Operating ...
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RX-8025 SA/NB 7.1.2. DC electrical characteristics (2) Item Symbol Input current with pull-down I FOE resistance Output current when OFF I OZ High-voltage Power V DETH supply mode detection Low-voltage V DETL voltage mode 7.2. AC Electrical Characteristics Unless otherwise ...
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RX-8025 SA/NB 8. Functional descriptions 8.1. Overview of Functions 1) Clock functions These functions enable setting, timing, and display of data including the year (last two digits), month, date, day, hour, minute, and second. Any (two-digit) year that is a ...
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RX-8025 SA/NB 8.2. Description of Registers 8.2.1. Register table Address Function 0 Seconds 1 Minutes 2 Hours 3 Days 4 Days 5 Months 6 Years 7 Digital Offset 8 Alarm_W ; Minute 9 Alarm_W ; Hour A Alarm_W ; Day ...
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RX-8025 SA/NB 8.2.2. Control register 1 (Reg E) Address Function E Control 1 (Default) ) The default value is the value that is read (or is set internally) after the PON bit has been set to "1," such as after ...
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RX-8025 SA/NB 8.2.3. Control register 2 (Reg F) Address Function F Control 2 (Default) 1) The default value is the value that is read (or is set internally) after the PON bit has been set to "1," such as after ...
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RX-8025 SA/ bit Bits marked with " " are RAM bits that can contain any value and are read/write-accessible. However, these bits are cleared to zero when the PON bit value is "1". 6) CTFG bit During ...
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RX-8025 SA/NB 8.2.4. Time counter (Reg Address Function 0 Seconds 1 Minutes 2 Hours □ ) " " indicates write-protected bits. A zero is always read from these bits. The time counter counts seconds, minutes, and hours. ...
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RX-8025 SA/NB 8.2.5. Day counter (Reg 3) Address Function 3 Days □ ) " " indicates write-protected bits. A zero is always read from these bits. The day counter is a divide-by-7 counter that counts from and ...
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RX-8025 SA/NB 8.2.7. Clock precision adjustment register (Reg 7) Address Function 7 Digital Offset (Default) ) 'Be sure to set a "0" for any bit whose value is shown above as "0". A zero is returned when any of these ...
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RX-8025 SA/NB 8.3. Clock Precision Adjustment Function The clock precision can be set ahead or behind. This function can be used to implement a higher-precision clock function, such as by: Enabling higher clock precision throughout the year by taking seasonal ...
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RX-8025 SA/NB 8.3.3. Adjustment examples Example 1) Setting time forward Objective) To adjust (advance) the clock precision when FOUT clock output is 32767.7 Hz (1) Determine the current amount of variance 32767.7 Hz (2) Calculate the optimum adjustment data (decimal ...
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RX-8025 SA/NB 8.4. Periodic Interrupt Function Periodic interrupt output can be obtained via the /INTA pin. Select among five periodic-cycle settings (once per 0.5 seconds (once per second), 1/60 Hz (once per minute), 1/3600 Hz (once ...
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RX-8025 SA/NB 8.4.2. Mode-specific output waveforms 1) Pulse mode A 2-Hz or 1-Hz clock pulse is output. The relation between the clock pulse and the count operation is shown below. CTFG bit /INTRA pin Note shown in ...
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RX-8025 SA/NB 8.5. Alarm W function The Alarm W function generates interrupt signals (output via the /INTB pin) that correspond to specified days, hours, and minutes. For description of the Alarm D function, which supports only hour and minute data, ...
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RX-8025 SA/NB 3) /12, 24 bit This bit is used to select between 12-hour clock operation and 24-hour clock operation. /12,24 Data Write / Read Be sure to select between 12-hour and 24-hour clock operation before writing the time data. ...
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RX-8025 SA/NB 8.6. Alarm D function The Alarm D function generates interrupt signals (output via the /INTA pin) that correspond to specified hours and minutes. For description of the Alarm W function, which supports only day, hour, and minute data, ...
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RX-8025 SA/NB 8.7. The various detection Functions The detection functions include detection of power-on resets, oscillation stops, and supply voltage drops, as well as reporting of detection results in corresponding bits of the address Fh (Control 2) register. The status ...
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RX-8025 SA/NB 8.7.2. Oscillation stop detection This function detects when internal oscillation has stopped. When an oscillation stop is detected, the /XST bit value becomes "0" "1" has already been written to the /XST bit, the /XST bit ...
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RX-8025 SA/NB 8.7.4. Estimation of status based on detection results The power supply status and clock status can be confirmed by reading the detection results indicated by the PON, /XST, and VDET bits. The following are status estimates based on ...
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RX-8025 SA/NB 8.8. Reading/Writing Data via the I 8.8.1. Overview C-BUS 2 The I C bus supports bi-directional communications via two signal lines: the SDA (data) line and SCL (clock) line. A combination of these two signals ...
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RX-8025 SA/NB 2 8.8.3. Starting and stopping I C bus communications START condition SCL SDA 1) START condition, repeated START condition, and STOP condition (1) START condition This condition regulates how communications on the I 2 C-BUS are started. SDA ...
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RX-8025 SA/NB 8.8.4. Data transfers and acknowledge responses during I 1) Data transfers Data transfers are performed in 8-bit (1 byte) units once the START condition has occurred. There is no limit on the amount (bytes) of data that are ...
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RX-8025 SA/NB 2 8.8. bus's basic transfer format The write/read steps are illustrated below. Master is transmitter (sending side), RTC is receiver (receiving side) Master is receiver (receiving side) RTC is transmitter (sending side Write via ...
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RX-8025 SA/NB 8.9. External Connection Example V DD Note : Pull-up resistor connections. SCL and SDA Connect to the system-power-supply. / INTA and / INTB When using these interrupt signals at battery backup, connect these pins to backup power supply. ...
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RX-8025 SA/NB 9. External Dimensions/Marking Layout 9.1. External Dimensions RX-8025 SA (SOP-14pin) External dimensions 10.1 0.2 # 0.35 1.27 The quartz oscillator's metal case may be visible in the area (on top) indicates in broken lines no ...
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RX-8025 SA/NB 10. Reference Data (1) Example of frequency/temperature characteristics = +25 C Typ Typ 0.035 -10 -20 -30 -40 -50 -60 -70 -80 -90 -100 -110 -120 -130 -140 ...
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RX-8025 SA/NB 11. Cautions for Use 11.1. Handling precautions Since this module includes a quartz oscillator, be careful to protect it from heavy impact or vibration. Also, be sure to note the following caution points regarding the C-MOS IC that ...
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RX-8025 SA/NB 1. Overview ..................................................................................................................1 2. Block Diagram ..........................................................................................................1 3. Description of Pins....................................................................................................2 3.1. Pin Layout ....................................................................................................................................2 3.2. Pin Functions ...............................................................................................................................2 4. Absolute Maximum Ratings 6. Frequency Characteristics 7. Electrical Characteristics................................................................................................3 8. Functional descriptions .............................................................................................5 8.1. Overview of Functions..................................................................................................................5 8.2. ...