TA8030S/F TOSHIBA BIPOLAR LINEAR INTEGRATED CIRCUIT SILICON MONOLITHIC TA8030S,TA8030F WATCHDOG TIMER The TA8030S TA8030F is a system reset IC for 5V supply voltage system. It is specially designed for microcomputer systems. It incorporates a watchdog timer for monitoring microcomputer operation and has many reset functions, including a reset timer output which will be given at power-on and another reset output which will be given when the supply voltage drops. With these functions, it helps build up a reliable system. TA8030S FEATURES l Watchdog timer l Power-on reset timer l Dual-reset output l SIP7 PIN SOP8 PIN TA8030F (TA8030S) (TA8030F) Weight SIP7- P-2.54A SOP8- P-225-1.27 1 : 0.7g (typ.) : 0.08g (typ.) 2002-02-27 TA8030S/F BLOCK DIAGRAM AND PIN LAYOUT Note: The TA8030S and TA8030F are the same chip; only the packages are different. 2 2002-02-27 TA8030S/F PIN DESCRIPTION PIN No. TA80305 TA8030F SYMBOL DESCRIPTION 1 1 WD Clock input pin for watchdog timer. If this IC is only used as a power-on reset timer, this pin is connected to RST1 . 2 2 TC Time setting pin for the reset and watchdog timers. R1 leads to VCC, and C1 leads to GND. 3 3 RST1 Supplies an NPN transistor open-collector output. Generates a reset signal determined by the CR combination connected to the TC pin. Supplies reset pulses intermittently if no clock is given to the WD pin. 4 4 GND Grounded 5 6 ADJ VCC detect voltage (1) adjusting pin. The detection voltage is 4.6V when this pin is grounded ; it is 3.5V when this pin is directly connected to VCC. 6 7 VCC Power supply pin for internal circuit. The output voltage can also be detected at this pin. 7 8 RST2 Supplies an NPN transistor open-collector output. It is the output pin for VCC detect voltage (2) . The detect voltage has a hysteresis of 0.17V. 5 NC Not connected pin.(Electrically,this pin is completely open.) 3 2002-02-27 TA8030S/F FUNCTIONAL DESCRIPTION About reset timer operation (See the timing chart) The following explains the TA8030S/F's voltage monitoring and reset timer operations and how to use these functions. (1) Voltage monitoring function (1) The power input VCC pin of this IC also serves as a voltage detection pin. When the VCC voltage exceeds 4.25V after the IC is powered on, the power-on reset timer starts operating from that point in time. When the IC is powered off and VCC drops below 4.25V, TC starts discharging and a reset signal is output when the voltage drops below 40% of VCC. Also, if VCC goes down for some reason during normal operation, a reset signal is output in the same way as described above, and when VCC is up again and exceeds 4.25V, the power-on reset timer starts operating from that point in time. The reset signal is forwarded to the RST1 pin. (2) Voltage monitoring function (2) The RST2 pin outputs a high when the VCC voltage rises above 4.65V and outputs a low when it falls below 4.48V. This function only monitors the voltage operating independently of Voltage monitoring function (1) and the reset timer function. Since when the voltage drops the RST2 output is inverted before a system reset signal is output from RST1 , this function can be used to inhibit writing to memory. Also, this voltage detection has 3s of response delay, td2, to prevent a reset from being generated inadvertently by minute noise. (For td2, refer to AC Electrical Characteristics.) (3) Power-on reset timer function The device is held in a reset state for a predetermined time until the 5V constant voltage stabilizes at power-on and until the oscillating clock of the CPU, etc. stabilizes before being freed from the reset state. This time can be set to any desired duration by using the appropriate resistor and capacitor values connected external to the TC pin. When the VCC voltage exceeds 4.25V, the system starts charging the capacitor and when this charging voltage exceeds 2V, the reset signal is inverted to deactivate the reset. (4) Watchdog timer function The WD pin between the CPU system and this IC is connected with an differential circuit. This is to ensure that when a failure occurs in the CPU system, a low signal is input to the WD pin no matter whether the clock output has stopped in the high or the low state. When the WD pin is fixed high, the watchdog timer stops operating. If only the power-on reset timer is needed in your system, connect the WD pin to RST1 . 4 2002-02-27 TA8030S/F TIMING CHART Note : See Electrical Characteristics for symbols in the timing chart. 5 2002-02-27 TA8030S/F MAXIMUM RATINGS (Ta = 25C) CHARACTERISTIC SYMBOL RATING UNIT VCC 17 V VIN (CK) -77 V Output Voltage VOUT 7 V Output Current Supply Voltage Input Voltage IOUT 10 mA Power Dissipation PD 300/280 mW Operating Temperature Topr -40 to 85 Storage Temperature Tstg -55 to 150 Lead Temperature-time Tsol 260 (10s) Note: PD : TA8030S/TA8030F ELECTRICAL CHARACTERISTICS (VCC = 5V, Ta = -40 to 85C) (1) DC CHARACTERISTICS CHARACTERISTIC Input Current Input Voltage Input Current Output Current Watchdog Timer Threshold Voltage Output Voltage Output Leakage Current SYMBOL TEST CIRCUIT PIN IIH WD IIL VIH WD VIL Current Consumption (2) TYP. MAX 1 VIN = 5V 0.1 0.17 0.35 1 VIN = -5V -0.06 -0.1 -0.2 2 2.2 2 0.6 UNIT mA V TC 4 VIN = 1.5V -2 2 A IOUT TC 4 VOUT = 4.2V 2.4 4 7.7 mA VTH3 (H) TC VTH3 (L) 3 3.5 4 4.5 3 1.75 2 2.25 V VOL RST1 5 IOUT = 2mA 0.5 V ILEAK RST2 6 VOUT = 7V 5 A 4.0 4.25 4.5 3 AJD = GND 4.3 4.6 4.9 3 ADJ = VCC 3.25 3.5 3.75 3 4.4 4.65 4.9 3 0.17 0.3 7 2.5 4.5 VTH1 (H) VCC VTH1 (L) VCC Detect Voltage (2) MIN IIN VTH1 VCC Detect Voltage (1) TEST CONDITION VTH2 (H) VTH2 ICC VCC VCC V V mA AC CHARACTERISTICS SYMBOL PIN TEST CIRCUIT Watchdog Timer TWD RST1 Reset Timer (1) TRST (1) Reset Timer (2) TRST (2) CHARACTERISTIC Input Pulse Width Transfer Delay Time TEST CONDITION MIN TYP. MAX UNIT 3 0.9 x C1R1 1.1 x C1R1 1.3 x C1R1 ms RST1 3 0.4 x C1R1 0.5 x C1R1 0.6 x C1R1 ms RST1 3 0.35 x C1 0.75 x C1 1.5 x C1 ms s TW WD 3 3 td1 RST1 3 tdHL (C1 = 0F) 3 10 td2 RST2 3 tdHL, tdLH 3 10 s Note:The unit for the C1 is Fthe unit for R1 is k. 6 2002-02-27 TA8030S/F TEST CIRCUIT (Number in show pin number of the TA8030S, those in ( ) show pin number of the TA8030F.) 1. IIHIIL (WD) 2. VIHVIL (WD) 3. VTH3 (H)(L) (TC) VTH1VTH1 (H)(L)VTH2 (H)V TH2AC CHARACTERISTICS 4. IINIOUT (TC) 7 2002-02-27 TA8030S/F 5. VOL ( RST1 ) ( RST 2 ) 6. ILEAK ( RST1 ) ( RST 2 ) 7 ICC 8. VOL (1)(2) ( RST1 ) ( RST 2 ) 8 2002-02-27 TA8030S/F RESET OUTPUT STANDARD CHARACTERISTICS 1. 2. RST1 RST 2 ADJ PIN PULL-UP / DOWN RESISTANCE VS VCC DETECT VOLTAGE 9 2002-02-27 TA8030S/F EQUIVALENT CIRCUIT DIAGRAM (WATCHDOG TIMER) EXAMPLE OF APPLICATION CIRCUIT RECOMMENDED CONDITIONS PART NAME MIN C1 R1 C2 TYP. MAX UNIT 0.01 100 F 10 100 k 2200 pF 10 2002-02-27 TA8030S/F Package Dimensions Weight: 0.7g (Typ.) 11 2002-02-27 TA8030S/F Package Dimensions Weight: 0.08g (Typ.) 12 2002-02-27 TA8030S/F RESTRICTIONS ON PRODUCT USE 000707EAA_S * TOSHIBA is continually working to improve the quality and reliability of its products. Nevertheless, semiconductor devices in general can malfunction or fail due to their inherent electrical sensitivity and vulnerability to physical stress. It is the responsibility of the buyer, when utilizing TOSHIBA products, to comply with the standards of safety in making a safe design for the entire system, and to avoid situations in which a malfunction or failure of such TOSHIBA products could cause loss of human life, bodily injury or damage to property. In developing your designs, please ensure that TOSHIBA products are used within specified operating ranges as set forth in the most recent TOSHIBA products specifications. Also, please keep in mind the precautions and conditions set forth in the "Handling Guide for Semiconductor Devices," or "TOSHIBA Semiconductor Reliability Handbook" etc.. * The information contained herein is presented only as a guide for the applications of our products. No responsibility is assumed by TOSHIBA CORPORATION for any infringements of intellectual property or other rights of the third parties which may result from its use. No license is granted by implication or otherwise under any intellectual property or other rights of TOSHIBA CORPORATION or others. * The information contained herein is subject to change without notice. 13 2002-02-27