RS5C348A RICOH Co.,Ltd., RS5C348A Datasheet
RS5C348A
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RS5C348A Summary of contents
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... Rx5C348A but cannot be disabled by any register settings for the Rx5C348B. The oscillation adjustment circuit is intended to adjust time counts with high precision by correcting deviations in the oscillation frequency of the crystal oscillator. These models come in an ultra-compact SSOP10 (RS5C348A/B), SSOP10G (RV5C348A/B), TSSOP10G (RT5C348B) ...
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Rx5C348A/B PIN CONFIGURATION BLOCK DIAGRAM 32kHz 32KOUT OUTPUT CONTROL OSCIN DIVIDER CORREC OSC -TION OSCOUT OSC DETECT /INTR INTERRUPT CONTROL 12345 Rev.2.01 Rx5C348A/B 10 VDD 32KOUT 1 9 SCLK OSCIN OSCOUT ...
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PIN DESCRIPTION Symbol Item CE Chip enable Input SCLK Serial Clock Input SI Serial Input SO Serial Output /INTR Interrupt Output 32KOUT 32kHz Clock Output OSCIN Oscillation OSCOUT Circuit Input / Output VDD Positive/Negative VSS Power Supply Input Rev.2.01 Description ...
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Rx5C348A/B ABSOLUTE MAXIMUM RATINGS Symbol Item VDD Supply Voltage 2 VI Input Voltage VO Output Voltage 1 Output Voltage 2 PD Power Dissipation Topt Operating Temperature Tstg Storage Temperature RECOMMENDED OPERATING CONDITIONS Symbol Item Vaccess Supply Voltage VCLK Time keeping ...
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DC ELECTRICAL CHARACTERISTICS (Unless otherwise specified: VSS=0V, VDD=3.0V, Topt=-40 to +85°C, Crystal oscillator 32768Hz,CL=7pF,R1=30kΩ) Symbol Item VIH “H” Input Voltage VIL “L” Input Voltage IOH “H” Output Current IOL1 “L” Output Current IOL2 IIL Input Leakage Current RDNCE Pull-down Resistance ...
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Rx5C348A/B AC ELECTRICAL CHARACTERISTICS Unless otherwise specified: VSS=0V,Topt=-40 to +85°C Input and Output Conditions: VIH=0.8×VDD,VIL=0.2×VDD,VOH=0.8×VDD,VOL=0.2×VDD,CL=50pF Symbol Item t CE Set-up Time CES t CE Hold Time CEH t CE Recovery Time CR f SCLK Clock SCLK Frequency t SCLK Clock ...
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... PACKAGE DIMENSIONS RS5C348A/B (SSOP10) 3.5±0 0.5 0.9MAX 0.1 0.2±0.1 0.1 M RV5C348A/B (SSOP10G) +0.3 0° to 10° 2.9 -0 +0.1 0.127 -0.05 0.5 0.1 0.2±0.1 0.15 M Rev.2.01 0° to 10° +0.1 0.15 -0.05 unit: mm unit Rx5C348A/B 12345 ...
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Rx5C348A/B RT5C348B (TSSOP10G) 2.9±0 0.5 0.1 0.2±0.1 0.15 M 12345 Rev.2.01 0° to 10° +0.1 0.13 -0.05 unit ...
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GENERAL DESCRIPTION Interface with CPU The Rx5C348A/B is connected to the CPU by four signal lines CE (Chip Enable), SCLK (Serial Clock), SI (Serial Input), and SO (Serial Output), through which it reads and writes data from and to the ...
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Rx5C348A/B frequency of a 32.768kHz crystal oscillator for output from the 32KOUT pin. The 32-kHz clock output can be disabled by certain register settings but cannot be disabled without manipulation of any two registers with different addresses to prevent disabling ...
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Address Mapping Address Register Name A3A2A1A0 Second Counter Minute Counter Hour Counter Day-of-week Counter Day-of-month ...
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Rx5C348A/B Register Settings Control Register 1 (ADDRESS Eh WALE DALE /12⋅24 WALE DALE /12⋅ *1) Default settings: Default value means read / written values when the XSTP bit is set to “1” due to ...
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TEST Test Bit TEST Description 0 Normal operation mode. 1 Test mode. The TEST bit is used only for testing in the factory and should normally be set to 0. (5) CT2, CT1, and CT0 Periodic Interrupt Selection Bits ...
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Rx5C348A/B CTFG Bit /INTR Pin (Increment of second counter) *1), *2) When the oscillation adjustment circuit is used, the interrupt cycle will fluctuate once per 20sec. or 60sec. as follows: Pulse Mode: The “L” period of output pulses will increment ...
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As such, the XSTP bit can be applied to judge the validity of clock and calendar data after power- drop in supply voltage. * When the XSTP bit is set to 1, all bits will ...
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Rx5C348A/B (5) /CLEN1 32kHz Clock Output Bit 1 (Rx5C348A) /CLEN1 Description 0 Enabling the 32-kHz clock circuit 1 Disabling the 32-kHz clock circuit Setting the /CLEN1 bit or the /CLEN2 bit (D4 in the control register specifies ...
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Time Counter (Address 0-2h) Second Counter (Address 0h S40 S20 0 S40 S20 0 Indefinite Indefinite Minute Counter (Address 1h M40 M20 0 M40 M20 Indefinite Indefinite 0 Hour Counter (Address 2h) ...
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Rx5C348A/B Calendar Counter (Address 4-6h) Day-of-month Counter (Address 4h D20 0 0 D20 Indefinite 0 0 Month Counter + Century Bit (Address 5h /19⋅ /19⋅20 Indefinite 0 0 ...
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Example: When the second digits read 00, 20, or 40, the settings of " 1" in the F6, F5, F4, F3, F2, F1, and F0 bits ...
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Rx5C348A/B Example of Alarm Time Setting Alarm Day-of-week Preset alarm time Sun. Mon. WW0 WW1 00:00 a.m. on all days 1 01:30 a.m. on all days 1 11:59 a.m. on all days 1 00:00 p.m. on Mon. to Fri. 0 ...
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Interfacing with the CPU DATA TRANSFER FORMATS (1) Timing Between CE Pin Transition and Data Input / Output The Rx5C348A/B adopts a 4-wire serial interface by which they use the CE (Chip Enable), SCLK (Serial Clock), SI (Serial Input), and ...
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Rx5C348A/B Writing Data Transfer Formats (1) 1-byte Writing Data Transfer Format The first type of writing data transfer format is designed to transfer 1-byte data at a time and can be selected by specifying in the address pointer a head ...
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Reading Data Transfer Formats (1) 1-byte Reading Data Transfer Format The first type of reading data transfer format is designed to transfer 1-byte data at a time and can be selected by specifying in the Address Pointer a head address ...
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Rx5C348A/B (3) Combination of 1-byte Reading and writing Data Transfer Formats The 1-byte reading and writing data transfer formats can be combined together and further followed by any other data transfer format. Example of Reading Modify Writing Data Transfer (For ...
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Considerations in Reading and Writing Time Data under special condition Any carry to the second digits in the process of reading or writing time data may cause reading or writing erroneous time data. For example, suppose a carry out of ...
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Rx5C348A/B Good Example Time span of 31µs or more CE SI F4h SO Address Pointer = Fh Transfer Format Register = 4h Bad Example (1) (Where the CE pin is once driven low in the process of reading time data) ...
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Configuration of Oscillation Circuit and Correction of Time Count Deviations Configuration of Oscillation Circuit VDD OSCIN OSCOUT CD A The oscillation circuit is driven at a constant voltage of approximately 1.2v relative to the level of the ...
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Rx5C348A/B Measurement of Oscillation Frequency VDD OSCIN 32768Hz OSCOUT 32KOUT VSS * 1) The Rx5C348A/B is configured to generate 32.768-kHz clock pulses for output from the 32KOUT pin frequency counter with 6 (more preferably 7) or more ...
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Course (A) When the time count precision of each RTC is not to be adjusted, the crystal oscillator intended for use in that RTC may have any CL value requiring no presetting. The crystal oscillator may be subject to frequency ...
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Rx5C348A/B Oscillation Adjustment Circuit The oscillation adjustment circuit can be used to correct a time count gain or loss with high precision by varying the number of 1-second clock pulses once per 20 seconds. The oscillation adjustment circuit can be ...
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Notes: 1) Oscillation adjustment does not affect the frequency of 32.768-kHz clock pulses output from the 32KOUT pin following 3 conditions are completed, actual clock adjustment value could be different from target adjustment value that set by oscillator ...
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Rx5C348A/B Oscillation Halt Sensing, and Supply Voltage Monitoring XSTP and VDET The oscillation halt sensing circuit is configured to record a halt on oscillation by 32.768-kHz clock pulses. The supply voltage monitoring circuit is configured to record a drop in ...
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Voltage Monitoring Circuit The supply monitoring circuit is configured to conduct a sampling operation during an interval of 7.8ms per second to check for a drop in supply voltage below a threshold voltage of 2.1 or 1.6v for the VDSL ...
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Rx5C348A/B Alarm and Periodic Interrupt The Rx5C348A/B incorporates the alarm interrupt circuit and the periodic interrupt circuit that are configured to generate alarm signals and periodic interrupt signals for output from the /INTR pin as described below. (1) Alarm Interrupt ...
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The alarm function can be set by presetting desired alarm time in the alarm registers (the Alarm_W Registers for the day-of-week digit settings and both the Alarm_W Registers and the Alarm_D Registers for the hour and minute digit settings) with ...
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Rx5C348A/B In the pulse mode, the increment of the second counter is delayed by approximately 92 µ s from the falling edge of clock pulses. Consequently, time readings immediately after the falling edge of clock pulses may appear to lag ...
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Typical Applications Typical Power Circuit Configurations Sample circuit configuration 1 OSCIN 32768Hz OSCOUT VDD *1) VSS Sample circuit configuration 2 OSCIN 32768Hz OSCOUT VDD Primary Battery VSS OSCIN 32768Hz OSCOUT VDD Secondary Battery VSS Rev.2.01 *1) Install bypass capacitors for ...
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Rx5C348A/B Connection of /INTR and 32KOUT Pin The /INTR pin follows the N-channel open drain output logic and contains no protective diode on the power supply side. As such, it can be connected to a pull-up resistor ...
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Connection With 3-Wire Serial Interface Bus To connect the Rx5C348A/B with 3-wire serial interface bus, shorten the SI and SO pins and connect them to the data line as shown in the figure below. CE0 Host CE1 SCLK DATA Rev.2.01 ...
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Rx5C348A/B Typical Characteristics Test circuit VDD OSCIN 32768Hz OSCOUT 32KOUT VSS Timekeeping Current vs. Supply voltage (with no 32-kHz clock output) (CE=Open, Output=Open, Topt=25 ° C,Rx5C348A) 1 0.8 0.6 0.4 0 Supply Voltage VDD(v) CPU ...
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Oscillation Frequency Deviation vs. External CG (VDD=3v,Topt=25 ° C, External CG=0pF as standard -10 -15 -20 -25 -30 -35 - External CG (pF) Oscillation Frequency Deviation vs. Operating Temperature (VDD=3v, Topt=25 ° C ...
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Rx5C348A/B Typical Software-based Operations Initialization at Power-on Start *1) Power-on *2) XSTP=1? Yes *4) Set Oscillation Adjustment Register and Control Register 1 and 2, etc. *1) After power-on from 0 volt, the start of oscillation and the process of internal ...
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Reading Time and Calendar Data (1) Ordinary Process of Reading Time and Calendar Data *1) CE ← H Read from Time Counter and Calendar Counter *2) CE ← L (2) Basic Process of Reading Time and Calendar Data with Periodic ...
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Rx5C348A/B (3) Applied Process of Reading Time and Calendar Data with Periodic Interrupt Function Time data need not be read from all the time counters when used for such ordinary purposes as time count indication. This applied process can be ...
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Interrupt Process (1) Periodic Interrupt Set Periodic Interrupt *1) Cycle Selection Bits Generate Interrupt to CPU No CTFG=1? Yes Conduct Periodic Interrupt *2) Control Register 2← (X1X1X011) (2) Alarm Interrupt WALE or DALE←0 *1) Set Alarm Min., Hr., and Day-of-week ...