M5295AP

M5295AL MITSUBISHI | Alldatasheet

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( / 8 )ELECTRIC MITSUBISHI M5295AL/P/FP MITSUBISHI<Dig.Ana.INTERFACE> WATCHDOG TIMER

DESCRIPTION

M5295A is a semiconductor integrated circuit which is designed for System Reset to detect +5V power supply. This IC keeps the operation microcomputer watching. When the system is abnormal,it generates Reset output until the system returns to normal states of the System. It is possible to vary the two detective voltage by connecting the resistor,so it is suitable to high quality and high performance system.

FEATURES

• Watch Dog Timer
• Power on Reset Timer
• Low circuit current 0.8mA(Typ,Vcc=5V)
• Wide Range of power supply BLOCK DIAGRAM APPLICATION Microcomputer Systems PIN CONFIGURATION (TOP VIEW) RECOMMENDED OPERATING CONDITIONS Outline 8P5(AL) Outline 8P4(AP) 8P2S-A(AFP) ADJ2 RST2 Vcc ADJ1 GND RST1 TC WD ADJ2 RST2 Vcc ADJ1GND RST1 TC WD 1 2 3 4 5 6 7 8 WD TC RST1 GND ADJ1 Vcc RST2 ADJ2 F.F F.F F.F W.D.T REFERENCE VOLTAGE GENERATOR CIRCUIT 51.2k49.6k 18.8k20.4k 1.24V 20k 30k

( / 8 )ELECTRIC MITSUBISHI M5295AL/P/FP MITSUBISHI<Dig.Ana.INTERFACE> WATCHDOG TIMER V ABSOLUTE MAXIMUM RATINGS (Ta=25°C,unless otherwise noted) Symbol Ratings Unit Supply voltage 15 Parameter Conditions Topr Operating temperature Power dissipation (2)AC FEATURES Symbol Test conditions Limits Unit Parameter Min. Typ. Max. -20 to +75 -55 to +125 Vcc mWPd tWD Watch dog timer Tstg Storage temperature Reset timer (1) ELECTRICAL CHARACTERISTICS (Ta=25°C,Vcc=5V,unless otherwise noted) (1)DC FEATURES Symbol Test conditions Limits Unit Parameter Min. Typ. Max. VIH VIL IOUT WD input current WD input voltage TC output current TC input current mA 0.06 IIN 0.25 -0.15 0.05 mA V V µA 0.15 mA ms 1.1 220 VIN Input voltage VOUT Output voltage Output current mA V V-10 to +10 800(SIP)/625(DIP)/440(FP) VIN=5V 0.2 K IOUT Thermal derating Ta≥25°C 8(SIP)/6.25(DIP)/4.4(FP) mW/°C VVH3(H) ILEAK VOL Threshold voltage of watch dog timer Output voltage Vcc detective voltage(1) V 3.7 VTH1 4.3 2.3 4.45 1.7 Output leak current V V µA V VOUT =4.2V VTH2(H) ADJ1 voltage RST1 on voltage RST2 on voltage 4.5 4.9 4.75 0.5 4.45 ADJ2 voltage V V V V 4.7 1.75 V Pin Circuit current V IIH IIL VIN=-5V VVH3(L) VTH2(L) ΔVTH2 RST1 RST2 Icc Vcc detective voltage(2) WD WD TC TC TC RST1 RST2 Vcc Vcc ADJ1 ADJ2 RST1 RST2 Vcc VIN=1.5V Vcc=1.2V,RL=4.7k Vcc=1.2V,RL=4.7k V V -0.1 0.8 3.3 0.1 0.5 4.05 4.25 4.6 0.05 0.1 0.2 1.17 1.46 1.07 1.34 1.61 0.5 1.50.8 Pin tRST(1) tRST(2) tWD IN td1 td2 Reset timer (2) Input pulse watch Transmittal delay time RST1 RST1 RST1 RST1 RST2 WD C=0.1µF,R1=10kΩ C=0.1µF,R1=10kΩ C=0.1µF,R1=10kΩ R1=10kΩ 0.5 830•C 0.5 0.5•C•R1 1.1 1.7 1.1•C•R1 ms s s s µs µs µs µs VOUT =15V IOUT =1mA

( / 8 )ELECTRIC MITSUBISHI M5295AL/P/FP MITSUBISHI<Dig.Ana.INTERFACE> WATCHDOG TIMER The Vcc rises up to 0.8V,then Reset1 and 2 generate Low output,and Rising up to 4.25V,charge of C1 begins. The Vcc rises up to 4.7V,then Reset2 generates high. The voltage at TC pin is 2V,then Reset2 generates high,when 4V,C1 is discharged and Reset1 generates Low. The voltage at TC pin falls to 2V,then Reset1 generates high unless normal clock signal is entered to WD pin,Reset1 repeats this operation. Before the voltage at TC pin reaches 4V,if normal clock signal is entered to WD pin,Low Reset1 is canceled. In the case of entrance of abnormal signal input, as the waveform of TC pin repeats charge and discharge of Reset1 alternatively from 2V to 4V,the Reset1 repeats high and low output operation. The Vcc falls to 4.6V,then Reset2 generates Low, this detective voltage has a 100mV hysteresis. When Vcc goes down to 4.25V(VTH1 ),the status of TC pin is switched to discharge.When the potentional at TC pin is detected being VTH3 (H) or VTH3 (L),the status of Reset1 becomes "low". 6 7, 3 4, 8 9 OPERATING EXPLANETION 1 2 3 4 5 6 7 8 9 1011 Vcc TC VIN RST1 RST2 VTH2(H) VTH1 tWD tRST(2)tRST (1) VTH3(H) VTH3(L) VTH2(L) VTH1

( / 8 )ELECTRIC MITSUBISHI M5295AL/P/FP MITSUBISHI<Dig.Ana.INTERFACE> WATCHDOG TIMER TERMINOLOGY tRST 1:Time required for TC pin potential to rise from 0V VTH 3(L) when Vcc is being applied. tWD : Time required for TC pin potential to rise from VTH 3(L) to VTH 3(H). tRST 2:Time required for TC pin potential to go down from VTH 3(H) to VTH 3(L). 1.Pin 2 (TC Pin) Charge Time and Discharge Time When input to WD pin is abnormal,TC pin output waveform is as shown below: 2.Pin 1 (WD Pin) Input Frequency, Input Pulse Width,Charge Time and Discharge Time When input to WD pin 1 is normal,TC pin 2 output waveform is as shown below: tRST (1)=0.51•C•R1 tWD =1.1•C•R1(charge time) tRST (2)=1000•C•in 2• 1000 R1 -3 4• 1000 R1 -1 (discharge time) C Vcc Resistance R1:10kΩ≤ R1 ≤30kΩ When R1 is 10kΩ ,tRST (2) is 830•C. t1=C•R1•in (charge time) t2=1000•C•in 2• 1000 R1 -3 1000 R1 +1 (discharge time) 5-x x-5 PIN 1 (WD PIN)INPUT REQUIREMENTS (1)Connect capacitor between WD pin and voltage input. (Refer to Section 3.) (2)Input cycle:No more than tWD (Discharge should start before voltage at WD pin reaches 4V.) 1.1•C•R1 < f (3)Input pulse width tWDIN :No more than t2 2 •Vcc 4 •Vcc t2t1 Pin 2 xV tWDIN 0.5 ms 50µs C=104 1ms tC=103 100µs Vcc=5V R1=10kΩ 2 3 4 DISCHARGE VOLTAGE x(V) InputTC tWD tRST (1) tRST (2) (Vcc=5V)

( / 8 )ELECTRIC MITSUBISHI M5295AL/P/FP MITSUBISHI<Dig.Ana.INTERFACE> WATCHDOG TIMER 3.Relationship between Input Pulse Width and Input Capacitance Cin When input to pin 1 is 1.5V or more,TC pin discharges electricity. Determine pulse width and input capacitance Cin with reference to the diagram shown on the right. 4.Vcc Detection Voltage Adjustment (1)Detection voltage 1(VTH 1)adjustment. VIN Cin 30k 20k Q1 is off when voltage at pin 1 is 1.5V or less. t3=Cin•5X10 •In4 1.5 Vin RST1 is output when t4 is longer than tWD . 49.6k 20.4k 1.24V R L Cin:10.000pF,t3=0.6ms Cin:1000pF,t3=0.6µs Cin:100pF,t3=6µs When t3 is too long,TC pin output waveform frequency changes as shown above.Set t3 to be sufficiently long to turn on Q1[tWDIN (3µs)or more] but not to exceed t2(Discharge time). (t2:Discharge time during normal input) VTH1(V) R1(kΩ ) R2(kΩ ) Detection voltage calculation formula 4.25 3.5 10.90 8.59 0.92 1.25 1.96 3.17 VTH 1= R02 R01+R02 X1.24(V) R 01=R1//49.6kΩ R 02=R2//20.4kΩ To adjust detection voltage 1,determine external resistance with the following equation: a. VTH >4.25V(R1=10kΩ ) b. VTH 1<4.25V(R2=5kΩ ) R2= 1 - 20.4k R1= 1 - 49.6k R0= VTH 1-1.24 8.322kX1.24 R0= 1.24 (VTH 1-1.24)4.016k Vin VIN Vin WD TC RST1 1.5V tWD t t t tt4

( / 8 )ELECTRIC MITSUBISHI M5295AL/P/FP MITSUBISHI<Dig.Ana.INTERFACE> WATCHDOG TIMER 854 6 7321 854 6 7321 M5295AL M5295AL VDDMCU/MPU CLOCK RST1 (RESET) RST2 (HOLD) Example of Backup Circuit with M5295AL (2)Detection voltage 2(VTH 2(L))adjustment 51.2k 18.8k 1.24V R L APPLICATION EXAMPLE OPERATION INSTRUCTIONS 1.When malfunction occurs due to noise or other related trouble,connect capacitance of approximately 1000pF between pin 5 and GND as well as pin 8 and GND to stabilize operation. 2.To adjust detection voltage,add resistance of 15kΩ or less to both Vcc and GND via adjusting pins. (Set detection voltage to no less than 3V.) 3.Set tWD and tRST(2) as shown below: 110µs≤tWD ≤1.1s 8.3µs≤tRST (2)≤83ms 10kΩ≤ R1 ≤30kΩ 4.Input clock pulses to pin 1 via capacitor.To determine capacitance,refer to "Relationship between Input Pulse Width and Input Capacitance Cin". RESET OUTPUT Backup switching voltage VTH(L) Switching voltage calculation formula 10KΩ 3.5V BACKUP POWER SUPPLY Vcc R3(kΩ ) R4(kΩ ) Detection voltage calculation formula 10.61 8.38 0.93 1.26 1.99 3.24 16.3 16.3 16.3 16.3 17.2 14.1 VTH 2(L)= R04 R03+R04 X1.24(V) R 03=R3//51.2kΩ R 04=R4//18.8kΩ VTH2(L)(V) 4.6 3.5 ΔVTH2(mV) 100 ΔVTH 2= 51.2k R03 X100(mV) To adjust detection voltage 2,determine external resistance with the following equations: a. VTH 2(L)>4.6V(R3=10kΩ ) b. VTH 2(L)<4.6V(R4=5kΩ ) R4= 1 - 18.8k R3= 1 - 51.2k R0= VTH 2(L)-1.24 8.37kX1.24 R0= 1.24 (VTH 2(L)-1.24)3.95k VTH 2(L)= R04 R03+R04 X1.24 R 03=R3//51.2k R 04=R4//18.8k (Note)Set backup switching voltage to be more than or equal to backup supply voltage. TO SYSTEM

( / 8 )ELECTRIC MITSUBISHI M5295AL/P/FP MITSUBISHI<Dig.Ana.INTERFACE> WATCHDOG TIMER TYPICAL CHARACTERISTICS THERMAL DERATING (MAXIMUM RATING) 200 400 600 800 0 25 50 75 100 125 AMBIENT TEMPERATURE Ta(°C) 1000 DETECTION VOLTAGE VS. SUPPLY VOLTAGE -40 0 20 40 80 100 AMBIENT TEMPERATURE Ta(°C) INTERRUPTION OUTPUT VOLTAGE VS. CIRCUIT CURRENT 0.5 1.0 1.5 2.0 2.5 CRITICAL OPERATION VOLTAGE CHARACTERISTICS 4.2 4.3 4.4 4.5 -40-20 0 20 40 4.1 4.6 4.7 4.8 4.9 60 80 100 120 -20 60 120 1.6 1.4 1.2 1.0 0.8 0.6 0.4 0.2 3.0 3.5 4.0 0 4 6 8 12 14 SUPPLY VOLTAGE Vcc(V) 2 10 16 0.2 0.3 0.4 0.5 0.6 0.7 0.8 M5295AL M5295AP M5295AFP DELAY TIME VS.DELAY CAPACITY CHARACTERISTICS DELAY CAPACITY C(µF) 0.01 0.1 1 100 2 3 75 2 3 75 2 3 750.01 100 CIRCUIT CURRENT VS. SUPPLY VOLTAGE SUPPLY VOLTAGE Vcc(V) 0.1 2 3 75 0.1 VTH2(H) VTH2(L) VTH1 Vcc=5V Vcc=5V tWD (R1=10kΩ ) R L=4.7kΩ tRST2R L=2.2kΩ R L=22kΩ R L=100kΩ (Icc FLUCTUATION CAUSED BY CIRCUIT OPERATION) R ST1 High R ST2 High AMBIENT TEMPERATURE Ta(°C)

( / 8 )ELECTRIC MITSUBISHI M5295AL/P/FP MITSUBISHI<Dig.Ana.INTERFACE> WATCHDOG TIMER OUTPUT SATURATION VOLTAGE VS. AMBIENT TEMPERATURE AMBIENT TEMPERATURE Ta(°C) -40 -20 0 20 40 60 80 100 120 0.1 0.2 0.3 0.4 WATCHDOG TIMER THRESHOLD VOLTAGE VS. AMBIENT TEMPERATURE AMBIENT TEMPERATURE Ta(°C) -40 -20 0 20 40 60 80 100 120 PIN TC INPUT CURRENT VS. AMBIENT TEMPERATURE AMBIENT TEMPERATURE Ta(°C) -40 -20 0 20 40 60 80 100 120 AMBIENT TEMPERATURE Ta(°C) -40 -20 0 20 40 60 80 100 120 1.6 1.4 1.2 1.0 0.8 0.6 0.4 0.2 AMBIENT TEMPERATURE Ta(°C) -40 -20 0 20 40 60 80 100 1200 120 160 200 240 280 320 0.1 1 10 1002 3 75 2 3 75 2 3 75 OUTPUT SATURATION VOLTAGE VS. LOAD CURRENT 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 WATCHDOG TIMER VS. AMBIENT TEMPERATURE RESET TIMER(2) VS. AMBIENT TEMPERATURE LOAD CURRENT I OUT (mA) Vcc=5V Vcc=5V Vcc=5V C=0.1µF Vcc=5V C=0.1µF R1=10kΩ Vcc=5V Vcc=5V R L=4.7kΩ VTH3(H) VTH3(L)