rs5c62 RICOH Co.,Ltd., rs5c62 Datasheet
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... REAL-TIME CLOCK RP/ RF/ RS5C62 APPLICATION MANUAL ELECTRONIC DEVICES DIVISION NO.EA-012-9803 ...
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The products and the product specifications described in this application manual are subject to change or dis- continuation of production without notice for reasons such as improvement. Therefore, before deciding to use the products, please refer to Ricoh sales ...
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... Reading and Writing Operations ...................................................................................... 2. Handling of CE Pin 3. Configuration of Oscillatory Circuit 4. Adjustment of Oscillation Frequencies ................................................................................................. 5. Interrupts ...................................................................................................... 6. Timer 7. Detection of Stop of Oscillation 8. Typical Power Supply Circuit 9. Typical Connection between RP/RF/RS5C62 and CPU .................................................................................. 10. Typical Characteristics 11. Typical Software-controlled Processes ................................................................... .................................................... ........................................................... ........................................................... ......................................................................... ...................................................................... .................................................................... ............................................................... ...
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QUESTIONS AND ANSWERS ON USE .............................................................................. PACKAGE DIMENSIONS TAPING SPECIFICATIONS ......................................................... ........................................................................... ...
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... Consumes very low power due to CMOS technology can be backed up by batteries. • Power supply voltage between 3.0 to 5.0V. • Time keeping supply voltage between 2.0 to 6.0V. • Package : 18pin DIP for RP5C62, 18pin SOP for RF5C62, 20pin SSOP for RS5C62. BLOCK DIAGRAM OSCIN ...
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... INTR outputs cyclic interrupts or alarm interrupts to CPU. It also operates when CE is low (at battery backup N-ch open drain output. Crystal oscillator of 32.768kHz must be connected between OSCIN and OSCOUT. Capacitance is connected externally between V OSCOUT, forming the oscillator circuit. V connects to +5V or +3V and V DD • RS5C62 (20pin SSOP ...
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... Time Keeping Supply voltage CLK f Crystal Oscillation Frequency XT V Pull-up Voltage for INTR, TMOUT pin PUP Conditions INTR, TMOUT Except INTR, TMOUT TA=25˚C ABSOLUTE MAXIMUM RATINGS Conditions INTR, TMOUT RP/RF/RS5C62 V =0V SS Ratings Unit –0.3 to +7.0 V –0 +0 –0.3 to +12.0 V –0 ...
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... RP/RF/RS5C62 DC ELECTRICAL CHARACTERISTICS Symbol Item V “H” input voltage IH1 V “L” input voltage IL1 V “H” input voltage IH2 V “L” input voltage IL2 V “H” output voltage OH1 V “L” output voltage OL1 V “L” output voltage OL2 I Input leak current ...
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... RR t AS(WR 3V±10 5V±20 0.8 ´ 2. 0.2 ´ 0. 0.8 ´ 2. 0.2 ´ 0. RP/RF/RS5C62 V =0V, Topt=–20 to +70˚C SS =3V±10% V =5V±20% DD MAX. MIN. MAX. 500 500 295 150 95 75 150 CEH t AH(RD ...
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... RP/RF/RS5C62 FUNCTIONAL DESCRIPTION 1. Addressing Address Bus Description sec. Counter sec. Counter min. Counter min. Counter hour Counter hour Counter ...
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... Specifies no change. 1 Specifies resetting of the timer conditional on restart. Alarm operation setting bit * 3 ALEN 0 Disables an alarm interrupt. 1 Enables an alarm interrupt. Time count operation setting bit * 4 WTEN 0 Disables a carry to the 1-second time digit. 1 Enables a carry to the 1-second time digit. RP/RF/RS5C62 Function Function Function Function 7 ...
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... RP/RF/RS5C62 2.2 Control Register 2 (BANK0/1 at “Eh” CTFG ALFG * * BSY CTFG ALFG Alarm time match indication bit * Cyclic interrupt indication bit * Time/calendar counter state indication bit * 1) The BSY bit is intended for only read operation and is not intended for write operation. ...
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... INTR Interrupt Setting the ADJ bit to “1” Setting the WTEN bit to “1” Completion of pulse for carry to second digit Setting the WTRST bit to “1” RP/RF/RS5C62 Alarm time match Interrupt Setting the CTFG bit to “0” MAX.122.1µs Completion of adjustment MAX.122.1µ ...
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... RP/RF/RS5C62 2.3 Control Register 3 (BANK0/1 at “Fh” WTRST TSTA TSTB The bit marked with “ ” is not intended for write operation This bit is intended for only write operation and always read as “0” When set to “1”, the WTRST bit specifies resetting of the lower-order counter than the 1 second counter ranging from 8Hz and 4Hz to 2Hz and 1Hz * conditional on restart. The WTRST bit is used to adjust the lower-order counter than the 1 second counter. After the WTRST bit is set to “ ...
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... INTR CTFG INTR Interrupt (1) Pulse mode (when 1Hz or 1/60Hz is selected) INTR Upward second count (2) Level mode (when 1Hz or 1/60Hz is selected) INTR Upward second count RP/RF/RS5C62 2 Remarks (Interrupt) Setting the CTFG bit to “0” 30.5µs Upward second count 30.5µs Upward second count 11 ...
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... RP/RF/RS5C62 2.6 Alarm Register (1-minute, 10-minute, 1-hour, and 10-hour) (BANK1 at “2h to 5h” AP The bits marked with “ ” are always read as “0” and not intended for write operation When enabling an alarm interrupt, non-existent minute and hour alarm digits must not be left (to prevent mismatching between clock time and alarm * time) ...
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... Specifies leap year indication (including February 29) (when (0,0) the LYE bit is set to “0”. Any other value Specifies normal year indication (not including February 29). Leap year indication selection bit * LYE 0 Enables leap year indication. 1 Disables leap year indication. RP/RF/RS5C62 2 Function 3,4 Function 13 ...
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... RP/RF/RS5C62 2.9 Timer Clock Selection Register (BANK1 at “Ch” Only the TM bit is intended for read operation. The D0 bit is always read as “TMFG”. The D2 and D1 bits are always read as “0” The bits are used to set cycles for the counters as shown in the table below. ...
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... RP/RF/RS5C62 0.244ms T 3 ...
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... RP/RF/RS5C62 3.2 Day-of-the-week Counter (BANK0 at “6h” The bits marked with “ ” are always read as “0” and not intended for write operation The day-of-the-week counter is incremented carry to the 1-day calendar digit Days of the week written to the W * (000)® ...
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... Upon driving low the CE pin, the inter- Writing operation facing input/output pins are disabled, preventing occur- rence of invalid leak current due to their floating. The Data bus CE pin must always be driven either high or low and must never be left floating. [1] [2] t CES t t AS(RD) AH(RD) [3] [ Valid [5] RP/RF/RS5C62 t CEH ...
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... RP/RF/RS5C62 1.2 Writing Operation The requirements for writing data to the internal registers and counters are: [1] holding the CE pin high, [2] per- forming the process of addressing through the pin inputs, then [3] driving low the CS pin, [4] causing the WR pin to transition from its high to low to high levels, and thereby [5] causing the pins to input data to be written ...
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... Timer operation is prohibit- ed upon detection of the stop of oscillation. 2) Avoid using the oscillator output of the RP/RF/RS5C62 (from the OSCOUT pin) to drive any other IC for the purpose of ensuring stable oscillation characteristics. Typical external components: X'tal : 32 ...
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... RP/RF/RS5C62 4. Adjustment of Oscillation Frequencies 4.1 Measurement of Oscillation Frequency The oscillation frequency can be measured by using the INTR pin output (a cyclic interrupt). Note that its mea- surement is affected by and cannot therefore be obtained with accuracy by the OSCIN pin input and the OSCOUT pin output, which are directly measured by such means as a probe. ...
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... D YES Optimize C END Make fine adjustment to oscillation END ) in general and equivalent series resistance (R1).) L to adjust oscillation frequencies to desired values (on the actual PCB in consideration of possible influ- D Reference RP/RF/RS5C62 1 * < If adjustment needs to be made to oscillation frequencies: > 2 with trimmer capacitor * Change ranking of oscillation ...
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... RP/RF/RS5C62 5. Interrupts Interrupts are available in the following two types: 1) Alarm interrupt: Requested upon driving low (turning on) the INTR pin in matching between preset alarm time (in minutes and hours) and time indicated by the time counter (in minutes and hours). 2) Cyclic interrupt: Requested upon driving low (turning on) the INTR pin with a preset cycle. ...
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... CTFG INTR Interrupt (See “2.5 Interrupt Cycle Selection Register”) (See “2.2 Control Register 2”) MAX Setting the TMR bit to “1” bit to “0” when the stop of oscillation is detected. 3 RP/RF/RS5C62 (Interrupt) Setting the CTFG bit to “0” 0.244ms ...
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... RP/RF/RS5C62 It is recommended to update the settings of the timer clock selection register at regular time intervals to improve the stability of timer operation. Elements Involved in Timer Timer clock selection register and TMFG bit TMR bit 7. Detection of Stop of Oscillation The stop of oscillation can be detected by monitoring the XSTP bit in the control register 2. Namely, the XSTP bit is switched from “ ...
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... CE pin is held low (in battery backup). (I) Connect the pull-up resistor to Point A in the left circuit diagram unless it is used while the CE pin is held low. (II) Connect the pull-up resistor to Point B in the left circuit diagram used while the CE pin is held low. RP/RF/RS5C62 G 25 ...
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... RP/RF/RS5C62 9. Typical Connection between RP/RF/RS5C62 and CPU RP/RF/RS5C62 and CPU Z80 Z80 A4 to A15 Address IORQ Decoder Powerdown Detector RP/RF/RS5C62 and CPU 8086 8086 Address Decoder ALE A0 to A19 A0 to A19 BHE BHE Latch AD0 ...
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... Current Consumption vs. Temperature Topt=25˚ =10pF – RP/RF/RS5C62 C =10pF, C =10pF D G X'tal : RL²35k½ Topt=25˚C Input pin : VDD or VSS Output pin : Open V = 5pF D C =10pF D C =20pF D C =30pF ...
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... RP/RF/RS5C62 10.5 Oscillation Frequency vs –20 –40 –60 –80 –100 (pF) G 10.7 Oscillation Frequency vs –1 –2 –3 – 10.9 Oscillation Start Time vs 2 5pF =10pF D C =20pF D C =30pF D 1.5 C =39pF D 1 0.5 –4 ...
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... Fur- 5 ther, assign a time-out period to exit from the loop for checking the BSY * NO bit. Wait 6) Start both the clock and alarm functions This typical process of initialization is applied at power-on from 0V and * not required at start-up from the backup battery RP/RF/RS5C62 29 ...
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... RP/RF/RS5C62 11.1-2 Initialization Subject to Setting of XSTP Bit Start Power-on from 0V YES XSTP=0? NO Control register 3 Control register 1 Interrupt cycle selection register BSY=0? 9 YES * Control register 2 Set 12-hour or 24-hour time scale, time and calendar counters, interrupt cycles, and timer output cycles Control register 1 30 ...
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... Restart time count operation. (The WTEN bit will automatically be set to * “1” in the control register 1 upon driving low the CE pin.) 7) When writing to the time and calendar counters, be sure to check the * BSY bit in the control register 2 by disabling a carry (by setting the WTEN bit to “0” ). RP/RF/RS5C62 31 ...
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... RP/RF/RS5C62 11.2-2 Reading from Time and Calendar Counters by Generating Cyclic Interrupt Output cyclic interrupt from INTR pin CTFG=0? 1 YES * CTFG 0 Read from time and calendar counters 11.2-3 Reading from Time and Calendar Counters by Dual Reading Read 1-second digit 1 * Read from the time and calendar counters (starting with address “ ...
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... Note that the start of oscillation normally requires a time period (oscilla Wait * tion start time) on the order of 0 seconds. Further, assign a time- out period to exit from loop for checking the XSTP bit in the control regis- ter 2. Notice RP/RF/RS5C62 OFF L Maximum of 200 µs 33 ...
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... RP/RF/RS5C62 QUESTIONS AND ANSWERS ON USE Below are listed questions and answers on using the RP/RF/RS5C62 under the following four categories: 1) Crystal oscillators 2) Hardware 3) Software 4) AC/DC electrical characteristics and others Category Question 1 : What are the causes of failure in adjustment of oscillation frequencies? (Subject to use of 1) Crystal ...
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... VDD pin input ranging from 2.5V to 5.5V (see the graph in 10.7 of “10. Typical Characteristics”). Questions and Answers and C , and G D and C . More specifically, the smaller the capacitance RP/RF/RS5C62 and G 35 ...
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... RP/RF/RS5C62 Category Sample Measurements of Variations in Oscillation Characteristics of ICs ppm –5 –10 Question 4 : Why should you avoid connecting either end of the oscillatory capacitors C VSS pin instead of the VDD pin? Answer 4: Because the oscillatory circuit is driven by a constant voltage of 2V relative to the VDD pin, either one end of the oscillatory capacitors C out exception ...
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... Answer 4: The INTR pin outputs the logical sum (OR alarm interrupt and a cyclic interrupt when they are generated in combination. Consequently, an attempt to disable an alarm interrupt by setting the ALFG bit to “0” may result in holding the INTR pin low when it outputs a cyclic inter- rupt as well. Questions and Answers RP/RF/RS5C62 37 ...
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... Question 8 : How can an alarm interrupt be output on a monthly basis? Answer 8: The RP/RF/RS5C62 are configured to issue a daily alarm and cannot be reconfigured to gener- ate an alarm interrupt on a monthly basis. Considering that they are designed to reduce cur- rent consumption as described in “Note” below, an advisable alternative action is to generate an alarm interrupt to the CPU on a daily basis and keep track of alarm dates in a software-con- trolled process ...
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... Typical Characteristics”). Their on-state current should preferably range from 10mA to 20mA or less and must not exceed the maximum current consumption for the package. Questions and Answers t ) indicates the time required to perform the process of addressing before AS RP/RF/RS5C62 39 ...
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... Question 8 : What are the ranges of operating voltages? Answer 8: Range of operating voltage of crystal oscillators only for time count operation: 2.0V to 6.0V. Range of operating voltage having any access to the CPU : 2.7V to 6.0V Incidentally, AC timing is available in three ratings : 3V±10%, 5V±10%, and 5V±20%. 40 Questions and Answers plus 0.3V System power VDD supply RP/RF/RS5C62 ...
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... Questions and Answers input) and the other pins opened (the term “opened” also SS pin input) and the other input pins connected to the DD pin input and the other output pins opened. The V RP/RF/RS5C62 pin input is set to 2.5V for DD 41 ...
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... RP/RF/RS5C62 PACKAGE DIMENSIONS RP5C62 (18pin DIP) • 2.54TYP. 1.5TYP. (0.100TYP.) (0.300TYP.) RF5C62 (18pin SOP) • 11.84MAX. (0.466MAX 1.27TYP. (0.050TYP.) RS5C62 (20pin SSOP) • +0.3 6.5 –0 0.45MAX. 0.22±0.1 0.1 42 (Unit: mm/(inch)) 24.8MAX. (0.976MAX 0.46 +0.15 –0.1 +0.006 (0.018 ) –0.004 10 9 +0.1 0.41TYP – ...
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... TAPING SPECIFICATIONS RF5C62 (18pin SOP) • 0.3±0.05 3.35±0.1 RS5C62 (20pin SSOP) • 0.3±0.1 2.7MAX. (Unit: mm) ø1.55±0.05 E1 User Direction of Feed. +0.1 ø1.5 –0 E1 User Direction of Feed. RP/RF/RS5C62 4.0±0.1 2.0±0.1 11.05 12±0.1 E2 4.0±0.1 2.0±0.05 6.7 8.0±0 ...
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RICOH COMPANY, LTD. ELECTRONIC DEVICES DIVISION HEADQUARTERS 13-1, Himemuro-cho, Ikeda City, Osaka 563-8501, JAPAN Phone 81-727-53-1111 Fax 81-727-53-6011 YOKOHAMA OFFICE (International Sales) 3-2-3, Shin-Yokohama, Kohoku-ku, Yokohama City, Kanagawa 222-8530, JAPAN Phone 81-45-477-1697 Fax 81-45-477-1694 • 1695 http://www.ricoh.co.jp/LSI/english/ RICOH CORPORATION ELECTRONIC ...