Preliminary CBC34123 EnerChip™ RTC SPI Real-Time Clock/Calendar with Integrated Backup Power Features • Integrated rechargeable solid state battery with power-fail detect and automatic switchover, providing greater than 30 hours of RTC backup • Smallest commercially available RTC with integrated backup power in compact 5mm x 5mm 1.4mm QFN package • Temperature compensated charge control • Integrated EnerChip™ recharged at VDD > 2.5V • SMT assembly - lead-free reflow solder tolerant • Real time clock provides year, month, day, weekday, hours, minutes, and seconds based on a 32.768 kHz quartz crystal • Resolution: seconds to years • Watchdog functionality • Freely programmable timer and alarm with interrupt capability • 3-line SPI-bus with separate, but combinable data input and output • Integrated oscillator load capacitors for CL = 7 pF • Internal Power-On Reset (POR) • Open-drain interrupt and clock output pins • Programmable offset register for frequency adjustment • Eco-friendly, RoHS compliant - tested Applications • Wireless sensors and RFID tags and other powered, low duty cycle applications. • Power bridging to provide uninterruptible RTC function during exchange of main batteries. • Consumer appliances that have real-time clocks; provides switchover power from main supply to backup battery. • Business and industrial systems such as: network routers, point-of-sale terminals, singleboard computers, test equipment, multi-function printers, industrial controllers, and utility meters. • Time keeping application • Battery powered devices • Metering • High duration timers • Daily alarms • Low standby power applications 5mm x 5mm x 1.4mm 16-QFN Package General Description The EnerChip RTC CBC34123-M5C combines a Real-Time Clock (RTC) and calendar optimized for low power applications with an integrated rechargeable solid state backup battery and all power management functions. The EnerChip RTC ensures a seamless transition from main power to backup power in the event of power loss. The integrated power management circuit ensures thousands of charge-discharge cycles from the integrated EnerChip and manages battery charging, discharge cutoff, power switchover, and temperature compensation to maximize the service life of the device. The CBC34123 provides greater than 30 hours of backup time in the event main power is interrupted. Typical blackout times are less than 4 hours. The EnerChip has extremely low self-discharge, recharges quickly, is non-flammable, and RoHS-compliant. The EnerChip is charged automatically anytime VDD is above 2.5V. Data is transferred serially via a Serial Peripheral Interface (SPI-bus) with a maximum data rate of 6.25 Mbit/s. Alarm and timer functions provide the option to generate a wake-up signal on an interrupt pin. An offset register allows fine tuning of the clock. Figure 1: CBC34123 Pin-out Diagram ©2012 Cymbet Corporation • Tel: +1-763-633-1780 • www.cymbet.com DS-72-31 V.08 Page 1 of 9 Preliminary CBC34123 EnerChip™ RTC 16 OSCI 1 OSCO OSCILLATOR 32.768 kHz DIVIDER CLOCKOUT CLKOE 11 CLKOUT 12 INT 3 MONITOR OFFSET FUNCTION 0Dh 6 VCHG 7 VEC 14 RESET 15 ENERCHIP AND CHARGER Offset_register TIMER FUNCTION 0Eh Timer_clkout 0Fh Countdown_timer EN CONTROL 2 TEST 13 VDD 5 VSS POWERON RESET WATCH DOG 8 SDO 9 SDI 10 SCL 4 CE SPI INTERFACE 00h Control_1 01h Control_2 02h Seconds 03h Minutes 04h Hours TIME 05h Days 06h Weekdays 07h Months 08h Years ALARM FUNCTION 09h Minute_alarm 0Ah Hour_alarm 0Bh Day_alarm 0Ch Weekday_alarm INTERRUPT Figure 2: CBC34123 Block Diagram with Registers Figure 3: Internal Schematic of CBC34123 EnerChip RTC ©2012 Cymbet Corporation • Tel: +1-763-633-1780 • www.cymbet.com DS-72-31 V.08 Page 2 of 9 Preliminary CBC34123 EnerChip™ RTC CBC34123 Input/Output Descriptions Pin Number Label Description 1 OSCO Oscillator output; high-impedance node; minimize wire length between quartz and package 2 TEST Test pin; not user accessible; connect to VSS or leave floating (internally pulled down) 3 INT/ Interrupt output (open-drain; active LOW) 4 CE Chip enable input (active HIGH) with internal pull down 5 VSS Ground 6 VCHG 4.1V (typical) charging source - connect to VBAT and/or optional EnerChip(s) 7 VEC Positive terminal of integrated thin film battery - connect to VCHG and nothing else 8 SDO Serial data output, push-pull; high-impedance when not driving; can be connected to SDI for single wire data line 9 SDI Serial data input; may float when CE is inactive 10 SCL Serial clock input; may float when CE is inactive 11 CLKOE CLKOUT enable or disable pin; enable is active HIGH; connect to VSS for low power operation 12 CLKOUT Clock output (open-drain) 13 VDD Supply voltage; positive or negative steps in VDD can affect oscillator performance; recommend 100nF decoupling close to the device (see Fig. 30) 14 RESET/ Output signal indicating RTC is operating in backup power mode 15 EN Charge pump enable; activates VCHG 4.1V (typ.) charging source OSCI Oscillator input; high-impedance node; minimize wire length between quartz and package 16 Package Dimensions (mm) Figure 4: CBC34123 Package (left: top view, looking through package; right: pad dimensions) EnerChip Properties Energy capacity (typical): Recharge time to 80%: Charge/discharge cycles: Operating temperature: Storage temperature: Minimum VDD to charge EnerChip: 5µAh 10 minutes >5000 to 10% depth-of-discharge -20°C to +70°C -40°C to +125°C 2.5V ©2012 Cymbet Corporation • Tel: +1-763-633-1780 • www.cymbet.com DS-72-31 V.08 Page 3 of 9 Preliminary CBC34123 EnerChip™ RTC Absolute Maximum Ratings PARAMETER / PIN CONDITION MIN TYPICAL MAX UNITS VDD with respect to GND 25°C GND - 0.3 - 6.0 V ENABLE Input Voltage 25°C GND - 0.3 - VDD+0.3 V VEC 25°C 3.0 - 4.15 V 25°C 3.0 - 4.15 V 25°C GND - 0.3 - 2.7 V (1) VCHG (1) RESET Output Voltage INT/, CE, TEST, OSCI, OSCO, SDO, SDI, SCL, CLKOE, CLKOUT (1) See NXP PCF2123 Data Sheet No external connections to these pins are allowed, except parallel EnerChips. Integrated EnerChip Thin Film Battery Operating Characteristics PARAMETER CONDITION MIN TYPICAL MAX UNITS Non-recoverable - 2.5 - % per year Recoverable - 1.5 - % per year Operating Temperature - -20 25 +70 °C Storage Temperature - -40 - +125 (2) °C 10% depth-of-discharge 5000 - - cycles 50% depth-of discharge 1000 - - cycles Self-Discharge (5 yr. average) 25°C Recharge Cycles (to 80% of rated capacity) 40°C Recharge Time (to 80% of rated capacity; 4.1V charge; 25°C) Capacity (see Figure 5) (1) 10% depth-of-discharge 2500 - - cycles 50% depth-of-discharge 500 - - cycles Charge cycle 2 - 11 22 Charge cycle 1000 - 45 70 25°C 5 - - (1) First month recoverable self-discharge is 5% average. (2) Storage temperature is for uncharged EnerChip CC device. minutes µAh Figure 5: Typical Discharge Characteristics of the CBC005 EnerChip Within the CBC34123 Note: All specifications contained within this document are subject to change without notice. ©2012 Cymbet Corporation • Tel: +1-763-633-1780 • www.cymbet.com DS-72-31 V.08 Page 4 of 9 Preliminary CBC34123 EnerChip™ RTC Important Reference Documents For complete specifications of the integrated PCF2123 Real-Time Clock, see here: http://www.nxp.com/documents/data_sheet/PCF2123.pdf . For complete specifications of the Cymbet 5µAh EnerChip and integrated power management circuit, see here: http://www.cymbet.com/pdfs/DS-72-21.pdf . The EnerChip and power management functions within the CBC34123 are configured as in Mode 1 (VMODE = GND) described in the CBC3105 data sheet. For guidelines regarding crystal selection and other important information pertaining to the PCF2123, see the UM10301 - User Manual for NXP Real Time Clocks, located here: http://www.nxp.com/documents/user_manual/UM10301.pdf Functional Description of Integrated PCF2123 Real-Time Clock The PCF2123 contains 16 8-bit registers with an auto-incrementing address counter, an on-chip 32.768 kHz oscillator with two integrated load capacitors, a frequency divider which provides the source clock for the Real Time Clock (RTC), a programmable clock output, and a 6.25 Mbit/s SPI-bus. An offset register allows fine tuning of the clock. All 16 registers are designed as addressable 8-bit parallel registers although not all bits are implemented. •The first two registers (memory address 00h and 01h) are used as control registers. •The memory addresses 02h through 08h are used as counters for the clock function (seconds up to years). The registers Seconds, Minutes, Hours, Days, Weekdays, Months, and Years are all coded in Binary Coded Decimal (BCD) format. When one of the RTC registers is written or read the contents of all counters are frozen. Therefore, faulty writing or reading of the clock and calendar during a carry condition is prevented. •Addresses 09h through 0Ch define the alarm condition. •Address 0Dh defines the offset calibration. •Address 0Eh defines the clock out and timer mode. •Address registers 0Eh and 0Fh are used for the countdown timer function. The countdown timer has four selectable source clocks allowing for countdown periods in the range from 244 ms up to four hours. There are also two pre-defined timers which can be used to generate an interrupt once per second or once per minute. These are defined in register Control_2 (01h). Low Power Operation Minimum power operation will be achieved by reducing the number and frequency of switching signals inside the IC, i.e., low frequency timer clocks and a low frequency CLKOUT will result in lower operating power. A second prime consideration is the series resistance Rs of the quartz used. Power Consumption with Respect to Quartz Series Resistance The series resistance acts as a loss element. Low RS will reduce current consumption further. ©2012 Cymbet Corporation • Tel: +1-763-633-1780 • www.cymbet.com DS-72-31 V.08 Page 5 of 9 Preliminary CBC34123 EnerChip™ RTC PCF2123 Register Overview 16 registers are available. The time registers are encoded in the Binary Coded Decimal (BCD) format to simplify application use. Other registers are either bit-wise or standard binary. Bit positions labeled as ‘-’ are not implemented and will return a ‘0’ when read. The bit position labeled as ‘--’ is not implemented and will return a ‘0’ or ‘1’ when read. Bit positions labeled with N should always be written with logic ‘0’ (1). Address Register name Bit 7 6 5 4 3 2 1 0 Control and status registers 00h Control_1 EXT_TEST N STOP SR N 12_24 CIE N 01h Control_2 MI SI MSF TI_TP AF TF AIE TIE Time and date registers 02h Seconds OS SECONDS (0 to 59) 03h Minutes -- MINUTES (0 to 59) 04h Hours - - AMPM HOURS (1 to 12) in 12 h mode HOURS (0 to 23) in 24 h mode 05h Days - - DAYS (1 to 31) 06h Weekdays - - - - 07h Months - - - MONTHS (1 to 12) 08h Years YEARS (0 to 99) - WEEKDAYS (0 to 6) Alarm registers 09h Minute_alarm AE_M MINUTE_ALARM (0 to 59) 0Ah Hour_alarm AE_H - AMPM HOUR_ALARM (1 to 12) in 12 h mode HOUR_ALARM (0 to 23) in 24 h mode 0Bh Day_alarm AE_D - DAY_ALARM (1 to 31) 0Ch Weekday_alarm AE_W - - MODE OFFSET[6:0] COF[2:0] - - WEEKDAY_ALARM (0 to 6) TE - Offset register 0Dh Offset_register Timer registers 0Eh Timer_clkout - 0Fh Countdown_timer COUNTDOWN_TIMER[7:0] CTD[1:0] [1] Except in the case of software reset, see Section 8.3.1.1. ©2012 Cymbet Corporation • Tel: +1-763-633-1780 • www.cymbet.com DS-72-31 V.08 Page 6 of 9 Preliminary CBC34123 EnerChip™ RTC POWER SUPPLY CURRENT CHARACTERISTICS OF INTEGRATED CBC910 POWER MANAGEMENT CIRCUIT ONLY Ta = -20ºC to +70ºC CHARACTERISTIC Quiescent Current (CBC910 power management circuit only; VDD > VRESET ; RTC current not included) EnerChip Cutoff Current (IQBATON adds to RTC current when in backup mode) SYMBOL CONDITION ENABLE=GND IQ ENABLE=VDD MIN MAX UNITS VDD=3.3V - 3.5 µA VDD=5.5V - 6.0 µA VDD=3.3V - 35 µA VDD=5.5V - 38 µA IQBATOFF VBAT < VBATCO, VOUT=0 - 0.5 nA IQBATON VBAT > VBATCO, ENABLE=VDD, IOUT=0 - 42 nA INTERFACE LOGIC SIGNAL CHARACTERISTICS VDD = 2.5V to 5.5V, Ta = -20ºC to +70ºC CHARACTERISTIC SYMBOL CONDITION MIN MAX UNITS High Level Input Voltage VIH - VDD - 0.5 - Volts Low Level Input Voltage VIL - - 0.5 Volts VDD 0.04V (1) - Volts High Level Output Voltage VOH VDD>VTH (see Figures 4 and 5) IL=10µA Low Level Output Voltage VOL IL = -100µA - 0.3 Volts Logic Input Leakage Current IIN 0<VIN<VDD -1.0 +1.0 nA (1) RESET tracks VDD; RESET = VDD - (IOUT x ROUT). RESET SIGNAL AC/DC CHARACTERISTICS VDD = 2.5V to 5.5V, Ta = -20ºC to +70ºC CHARACTERISTIC SYMBOL CONDITION MIN MAX UNITS VDD Rising to RESET Rising tRESETH VDD rising from 2.8V TO 3.1V in <10µs 60 200 ms VDD Falling to RESET Falling tRESETL VDD falling from 3.1V to 2.8V in <100ns 0.5 2 µs TRIP Voltage VDD Rising VRESET VMODE=GND 2.85 3.15 V RESET Hysteresis Voltage (VDD to RESET) VHYST VMODE=GND 45 75 mV ©2012 Cymbet Corporation • Tel: +1-763-633-1780 • www.cymbet.com DS-72-31 V.08 Page 7 of 9 Preliminary CBC34123 EnerChip™ RTC CHARGE PUMP CHARACTERISTICS (PERTAINS TO INTEGRATED CBC910 POWER MANAGEMENT CIRCUIT) (NOTE: THIS TABLE PROVIDES IMPORTANT INFORMATION WHEN CONNECTING ADDITIONAL ENERCHIPS TO VCHG.) VDD = 2.5V to 5.5V, Ta = -20ºC to +70ºC CHARACTERISTIC SYMBOL ENABLE=VDD to Charge Pump Active tCPON ENABLE Falling to Charge Pump Inactive tCPOFF CONDITION MIN MAX UNITS 60 80 µs 0 1 µs - 120 KHz (1) 150 300 Ω ENABLE to 3rd charge pump pulse, VDD=3.3V - Charge Pump Frequency fCP Charge Pump Resistance RCP Delta VBAT, for IBAT charging current of 1µA to 100µA CFLY=0.1µF, CBAT=1.0µF VCHG Output Voltage VCP CFLY=0.1µF, CBAT=1.0µF, IOUT=1µA, Temp=+25ºC 4.075 4.125 V VCHG Temp. Coefficient TCCP IOUT=1µA, Temp=+25ºC -2.0 -2.4 mV/ºC ICP IBAT=1mA CFLY=0.1µF, CBAT=1.0µF 1.0 - mA ENABLE=VDD 2.5 - V Charge Pump Current Drive Charge Pump on Voltage (1) VENABLE fCP = 1/tCPPER ADDITIONAL CHARACTERISTICS Ta = -20ºC to +70ºC CHARACTERISTIC VBAT Cutoff Threshold SYMBOL VBATCO Cutoff Temp. Coefficient TCCO VBAT Cutoff Delay Time tCOOFF CONDITION LIMITS UNITS MIN MAX 2.75 3.25 V +1 +2 mV/ºC 40 - ms IOUT=1µA VBAT from 40mV above to 20mV below VBATCO IOUT=1µA Note: All specifications contained within this document are subject to change without notice ©2012 Cymbet Corporation • Tel: +1-763-633-1780 • www.cymbet.com DS-72-31 V.08 Page 8 of 9 Preliminary CBC34123 EnerChip™ RTC Ordering Information EnerChip CC Part Number Description Notes CBC34123-M5C EnerChip RTC in 5mm x 5mm x 1.4mm 16-QFN Land Grid Array Shipped in Tube CBC34123-M5C-TR1 CBC34123-M5C-TR5 EnerChip RTC in 5mm x 5mm x 1.4mm 16-QFN Land Grid Array Tape-and-Reel - 1000 pcs (TR1) or 5000 pcs (TR5) per reel CBC-EVAL-12 EnerChip RTC Evaluation Kit USB based Eval Kit with CBC34123 tab board U.S. Patent No. 8,144,508. Additional U.S. and Foreign Patents Pending Disclaimer of Warranties; As Is The information provided in this data sheet is provided “As Is” and Cymbet Corporation disclaims all representations or warranties of any kind, express or implied, relating to this data sheet and the Cymbet EnerChip product described herein, including without limitation, the implied warranties of merchantability, fitness for a particular purpose, non-infringement, title, or any warranties arising out of course of dealing, course of performance, or usage of trade. Cymbet EnerChip products are not authorized for use in life critical applications. Users shall confirm suitability of the Cymbet EnerChip product in any products or applications in which the Cymbet EnerChip product is adopted for use and are solely responsible for all legal, regulatory, and safety-related requirements concerning their products and applications and any use of the Cymbet EnerChip product described herein in any such product or applications. Cymbet, the Cymbet Logo, and EnerChip are Cymbet Corporation Trademarks ©2012 Cymbet Corporation • Tel: +1-763-633-1780 • www.cymbet.com DS-72-31 V.08 Page 9 of 9