NJM2102 SYSTEM RESET IC ■ GENERAL DESCRIPTION The NJM2102 Possesses two functions. One is to detect a voltage which decays from the desired voltage and generate a warning signal. And also, the NJM2102 holds the warning signal for a certain term after the specified voltage is obtained or recovered. The other one (Watch Dog Timer) is to identify missing clocks of microprocessors. Therefore, it should be said that the NJM2102 is ideal to protect any microprocessors from the fales operations induced by undesired condition. ■ FEATURES ● Internal Watch Dog Timer ● Precise Detection of Supply Voltage Down ● Package Outline ● Bipolar Technology (4.2V ±2.5%) DIP8, DMP8, SIP8 ■ PACKAGE OUTLINE NJM2102D (DIP8) NJM2102M (DMP8) NJM2102L (SIP8) ■ PIN CONFIGURATION NJM2102D NJM2102M NJM2102L PIN FUNCTION 1. CT 2. RESET 3. CK 4. GND 5. V+ 6. VREF 7. VS 8. RESET ■ BLOCK DIAGRAM Ver.2013-03-06 -1- NJM2102 (Ta=25°C) ■ ABSOLUTE MAXIMUM RATINGS PARAMETER Supply Voltage Input Voltage Input Voltage SYMBOL V+ VS VCK Power Dissipation PD Operating Temperature Range Storage Temperature Range Topr Tstg RATINGS 20.0 V++0.3 (<20.0) 20.0 (DIP8) 500 (DMP8) 300 (SIP8) 800 -40 to +85 -40 to +125 UNIT V V V mW °C °C (V+=5V, Ta=25°C) ■ ELECTRICAL CHARACTERISTICS PARAMETER Supply Current Detection Voltage 1 Detection Voltage 2 Hysteresis Width Reference Voltage Supply Voltage Regulation Reference Voltage Load Regulation CK Input Threshold Voltage CK Input Current 1 CK Input Current 2 CT Charge Current 1 CT Charge Current 2 CT Discharge Current 1 CT Discharge Current 2 SYMBOL ICC VSL VSH VHYS VREF ∆VREF1 ∆VREF2 VTH IIH IIL ICTC1 ICTC2 ICTD1 ICTD2 CONDITION Watch Dog Timer Operating Falling Down Supply Voltage Rising Up Supply Voltage VHYS = VSL - VSH V+ = 3.5V to 18V IOUT = -200µA to +5µA VCK = 5.0V VCK = 0.0V VCT = 1.0V Watch Dog Timer Operating VCT = 0.0V Power ON Reset Operating VCT = 1.0V Watch Dog Timer Operating VCT = 0.0V Power ON Reset Operating VS=Open. IRESET = -5µA MIN. 4.10 4.20 50 1.217 -10 -5 0.70 -1.0 20 0.6 6 100 TYP. 0.65 4.20 4.30 100 1.235 +3 1.24 0 -0.1 50 1.4 9 600 MAX. 1.00 4.30 4.40 150 1.253 +10 +5 1.90 1.0 110 3.0 13 - UNIT mA V V mV V mV mV V µA µA µA µA µA µA 4.5 4.9 - V High Level Output Voltage 1 VOH1 High Level Output Voltage 2 VOH2 4.9 - V VOL1 VS=0V, IRESET = -5mA VS=0V, IRESET =3mA 4.5 Output Saturation Voltage 1 - 0.2 0.4 V Output Saturation Voltage 2 VOL2 VS=0V, IRESET =10mA - 0.3 0.5 V Output Saturation Voltage 3 Output Saturation Voltage 4 VOL3 VOL4 - 0.2 0.3 0.4 0.5 V V Output Sink Current 1 IOL1 VS=Open. IRESET=3mA VS=Open. IRESET=10mA VS=0V, VRESET =1.0V 20 70 - mA Output Sink Current 2 IOL2 VS=Open. VRESET =1.0V 20 70 - mA - 0.8 1.2 V - 0.8 1.2 V RESET Minimum Supply Voltage 1 RESET Minimum Supply Voltage 2 VCCL1 VCCL2 VRESET =0.4V, IRESET =0.2mA + VRESET=V -0.1V, RL (2Pin-GND)=1MΩ (V+=5V, Ta=25°C) AC CHARACTERISTICS PARAMETER V+ Input Pulse Width SYMBOL TPI CONDITION VCC 5V 4V or MIN. - TYP. 10 MAX. - UNIT µS - 1.8 - µS - 12 10 2 - µS mS mS CK Input Pulse Width TCKW CK CK Input Frequency Watch Dog Timer Watching Time Watch Dog Timer Reset Time TCK TWD TWR CT=0.1µF CT=0.1µF Reset Signal Hold Time TPR CT=0.1µF, V - 100 - mS + Propagation Delay from V TPD1 2 - µS TPD2 tR tF RESET Pin, RL=2.2kΩ, CL=100pF RESET Pin RL=2.2kΩ, CL=100pF RL=2.2kΩ, CL=100pF RL=2.2kΩ, CL=100pF - Propagation Delay from V+ Output Rise Time Output Fall Time - 3 1.0 0.1 - µS µS µS -2- + Ver.2013-03-06 NJM2102 ■ TIMING CHART Ver.2013-03-06 -3- NJM2102 ■ TERMINAL FUNCTION PIN. NO -4- SYMBOL FUNCTION 1 CT Pin Connection to Capacitor, Set the reset holding time 2 RESET Reset Output 3 CK Clock Input INSIDE EQUIVALENT CIRCUIT Ver.2013-03-06 NJM2102 ■ TERMINAL FUNCTION PIN. NO SYMBOL FUNCTION 4 GND Ground 5 V+ Operating Voltage 6 VREF Ref Amp Output 7 VS Comparator S Input 8 RESET Reset Output Internal pull up resistor Ver.2013-03-06 INSIDE EQUIVALENT CIRCUIT -5- NJM2102 ■ TYPICAL CHARACTERISTICS -6- Operating Current vs. Operating Voltage Output Voltage vs. Operating Voltage Output Voltage vs. Operating Voltage Detect Voltage vs. Ambient Temperature Satulation Voltage vs. Output Sink Current Satulation Voltage vs. Output Sink Current Ver.2013-03-06 NJM2102 ■ TYPICAL CHARACTERISTICS High Level Output Voltage vs. High Level Output Current Reference Voltage vs. Reference Current High Output Voltage vs. High Level Output Current Reference Voltage vs. Ambient Temperature Reference Voltage vs. Operating Voltage Ver.2013-03-06 -7- NJM2102 ■ TYPICAL CHARACTERISTICS Reset Hold Time at Transient Reset Time TWR (Sec) Timing Capacitor CT (µF) 1 Watch Dog Timer observation time Minimum Input Pulse Width vs. C TPI (Sec) -8- Ver.2013-03-06 NJM2102 ■ APPLICATION CIRCUIT 1. 5V Supply Voltage Supervisory and Watch-dog timer ● Voltage Supply is detected through VS. Detected Voltage is VSH, VSL. ● If minimum input pulse width TPI needs extend, add external capacitor C between VS terminal and GND. (Please refer to TYPICAL CHARACTERISTICS : Minimum Input Pulse Width vs C) 2. 5V Supply Voltage Supervisiory (Externally fine tunning type) ● VS detecting Voltage can be externally adjusted. ● Detecting Voltage can be decided by divider resistor of IC inside. Detecting Voltage can be set by external R1, R2. The external resistor R1, R2 are required to be set in value less than 1 / 10 in comparing to divideing resistor of IC inside. Please refere to following Table. Ver.2013-03-06 R1(kΩ) R2(kΩ) Detecting Voltage : VSL(V) 10 3.9 4.34 Detecting Voltage : VSH(V) 4.44 9.1 3.9 4.08 4.18 -9- NJM2102 3. Compulsory Resetting attached (Reset Hold attached) ● *Pin 7 to be grounded when SW. ON. RESET (8pin) become Low : RESET (pin2) become HIGH. ● By putting signal in the RESET pin, and Tr swich ON RESET pin become LOW and RESET pin HIGH. [CAUTION] The specifications on this databook are only given for information , without any guarantee as regards either mistakes or omissions. The application circuits in this databook are described only to show representative usages of the product and not intended for the guarantee or permission of any right including the industrial rights. - 10 - Ver.2013-03-06