NCV8881PWR2G ON Semiconductor, NCV8881PWR2G Datasheet
NCV8881PWR2G
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NCV8881PWR2G Summary of contents
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NCV8881 1.5A Automotive Buck Regulator with Watchdog The NCV8881 consists of a Buck switching regulator (SMPS) with a combination SMPS output undervoltage monitor and CPU watchdog circuit. In addition, two fixed−voltage low dropout regulator outputs are provided, and share an ...
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IGNITION RIGBUF BUFFER FROM CPU WATCHDOG OUT RDLY TO CPU RESET RRESB ENABLE R1 R2 SYNC ROSC RIGBUF IGNITION BUFFER BUFFERED IGNBUF ENABLE 1 QIB WATCHDOG INPUT WDI 2 WATCHDOG RDLY TIMER 3 RDLY CPU RESET RRESB RESB 4 QRB ...
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MAXIMUM RATINGS Rating Min/Max Voltage on WDI Min/Max Voltage on RDLY Min/Max Voltage on RESB Min/Max Voltage on EN Max EN Current Min EN Current (with zero VIN voltage) Min/Max Voltage on SYNC Min/Max Voltage on ROSC Min/Max Voltage COMP ...
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PIN FUNCTION DESCRIPTIONS Pin No. Symbol 1 IGNBUF This open drain output is pulled low whenever the EN signal is latched and a low level is recognized at the EN input. 2 WDI CMOS compatible Watchdog pulse input from a ...
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GENERAL SPECIFICATIONS ELECTRICAL CHARACTERISTICS (V for the temperature range −40° 150 °C unless noted otherwise, and are guaranteed by test, design or statistical correlation. J Parameter VIN UVLO START Voltage Threshold STOP Voltage Threshold VIN UVLO Hysteresis VIN ...
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LDO REGULATORS ELECTRICAL CHARACTERISTICS (V for the temperature range −40° 150°C unless noted otherwise, and are guaranteed by test, design or statistical correlation. J Parameter 5P0 OUTPUT Output UV START Threshold Output UV STOP Threshold Output UV Hysteresis ...
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SMPS REGULATOR ELECTRICAL CHARACTERISTICS (V otherwise) Min/Max values are valid for the temperature range −40°C vT design or statistical correlation. Parameter SOFT−START Soft−Start Completion Time VOLTAGE REFERENCE (FB Pin) FB Voltage (COMP connected to FB) FB PIN MONITOR (SMPS Output ...
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SMPS REGULATOR ELECTRICAL CHARACTERISTICS (V otherwise) Min/Max values are valid for the temperature range −40°C vT design or statistical correlation. Parameter SYNCHRONIZATION Minimum High Pulse Width Minimum Low Pulse Width DUTY CYCLE LIMITATIONS Minimum Off Time Minimum On Time CURRENT ...
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WATCHDOG ELECTRICAL CHARACTERISTICS (V the temperature range −40° 150°C unless noted otherwise, and are guaranteed by test, design or statistical correlation. J Parameter WATCHDOG INPUT (WDI pin) Input High Voltage Input Low Voltage Input Current Threshold Frequency RDLY ...
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FAULT RESPONSES INPUTS FAULT EVENT EN EN Latch VIN Undervoltage L UNLATCH VIN Undervoltage H UNLATCH VIN Overvoltage L Stays Latched VIN Overvoltage H Stays Latched Thermal Shutdown L Stays Latched Thermal Shutdown H Stays Latched 5P0 Out of Regulation ...
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TYPICAL PERFORMANCE CHARACTERISTICS 14.0 12.0 13.2 V SUPPLY 10.0 8.0 6.0 V SUPPLY 6.0 4.0 2.0 0.0 −40 − TEMPERATURE (°C) Figure 3. Supply Current (EN Low) vs. Temperature 50.0 45.0 40.0 35.0 30.0 25.0 ...
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TYPICAL PERFORMANCE CHARACTERISTICS 20.8 20.7 20.6 20.5 20.4 20.3 20.2 20.1 20.0 19.9 19.8 −40 − TEMPERATURE (°C) Figure STOP Voltage vs. IN Temperature 810 808 806 804 802 800 798 796 ...
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TYPICAL PERFORMANCE CHARACTERISTICS 8.500 8.495 8.490 8.485 8.480 8.475 8.470 9.0 12.0 15.0 VOLTAGE (V) Figure 15. 8P5 Output Voltage vs. Input Voltage 200 180 160 140 120 100 80 60 −40 − TEMPERATURE (°C) ...
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TYPICAL PERFORMANCE CHARACTERISTICS 0.05 0.04 0.03 0.02 0.01 0.00 −40 − TEMPERATURE (°C) Figure 21. RESB Low Voltage vs. Temperature 1.050 1.045 1.040 1.035 1.030 1.025 1.020 1.015 1.010 −40 − ...
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TYPICAL PERFORMANCE CHARACTERISTICS 750 ROSC = 0 740 730 720 710 700 690 680 670 660 650 −40 − TEMPERATURE (°C) Figure 27. Maximum Switching Frequency vs. Temperature 80.0 79.0 78.0 77.0 76.0 75.0 −40 ...
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TYPICAL PERFORMANCE CHARACTERISTICS 5.30 5.20 5.10 5.00 4.90 4.80 4.70 4.60 −40 − TEMPERATURE (°C) Figure 33. Soft−Start Time vs. Temperature 650 600 550 500 450 400 350 300 250 200 150 100 50 0 ...
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TYPICAL PERFORMANCE CHARACTERISTICS 350 T = 25°C J 300 250 200 150 100 LOAD CURRENT (kW) Figure 39. 5P0 Dropout Voltage vs. Load Current 250 T = 25°C J 200 150 ...
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INPUT VOLTAGE VIN is the power supply input for all NCV8881 functions. Prior to the appearance of a valid high at the Enable input (EN pin), VIN voltage above the V STRT a low level at the Reset output (RESB). ...
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RESB LOW LDOS ON, SMPS OFF Temp > Shutdown RESB LOW LDOS, SMPS OFF LDOMON ACTIVE VIN < 19V & Temp <Shutdown 5P0 or 8P5 in regulation UNLATCH ENABLE Temp <Shutdown 1 SS Timer Expired 2 SMPS in regulation 3 ...
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ENABLE (EN PIN) After VIN rises above below V STRT maintain a standby mode which keeps the switching regulator, Watchdog Circuit, and LDO outputs off, and minimizes supply current. In this state the RESB output is low. ...
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ENABLE SIGNAL R1 EXTERNAL RESISTORS R2 Figure 44. Enable Input Hysteresis Mechanism When the EN pin is below V ENSTHL parallel with RPDOWN making the internal resistance from the EN pin to ground lower than when the EN pin is ...
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IGNITION BUFFER The Ignition Buffer output IGNBUF reports the EN pin voltage level (high or low) detected by the EN input circuitry when the EN signal is latched. The NCV8881 will pull the IGNBUF output low if the Enable signal ...
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V overloading the input supply. VOLTAGE REFERENCE An internal, temperature compensated Bandgap voltage reference provides the SMPS Error Amplifier and the 5P0 and 8P5 linear regulators with ...
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VIN ENABLE 8P5 5P0 SOFT−START TIMER Regulation Threshold Short−Circuit Threshold SMPS OUTPUT Figure 47. SMPS Overload after Successful Startup #1 SMPS OVERLOAD AFTER SUCCESSFUL STARTUP # VIN ENABLE 8P5 5P0 SOFT−START TIMER Regulation Threshold ...
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VIN ENABLE 8P5 5P0 SOFT−START TIMER Regulation Threshold Short−Circuit Threshold SMPS OUTPUT Figure 49. SMPS Short−Circuit during Startup VIN ENABLE 8P5 5P0 SOFT−START TIMER Regulation Threshold Short−Circuit Threshold SMPS OUTPUT Figure 50. ...
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VIN ENABLE 8P5 5P0 SOFT−START TIMER Regulation Threshold Short−Circuit Threshold SMPS OUTPUT Figure 51. SMPS Short−Circuit After Successful Startup #2 WATCHDOG WATCHDOG FUNCTION The Watchdog function monitors the WDI input to check that WDI pulses arrive ...
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VIN ENABLE POR DELAY BOOT DELAY RESB WATCHDOG DELAY WDI 3.3V 5V Figure 52. Watchdog Never Appears; EN Input HIGH WATCHDOG STUCK HIGH, THEN RECOVERS; ENABLE = HIGH VIN ...
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WATCHDOG STUCK LOW, THEN RECOVERS; ENABLE = HIGH VIN ENABLE POR DELAY BOOT DELAY RESB WDI 3.3V 5V Figure 54. Watchdog Stuck LOW, Then Normal; EN Input HIGH VIN ENABLE POR DELAY RESB BOOT ...
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WATCHDOG STUCK HIGH; ENABLE = LOW, THEN EN = HIGH RESTARTS VIN POR ENABLE DELAY RESB BOOT DELAY WDI NORMAL RESPONSE 3.3V 5V Figure 56. Watchdog Stuck HIGH, EN Input LOW; then EN Goes HIGH ...
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R1 with R2 set at 1 kW. SMPS Snubber A resistor and ceramic capacitor must be connected in series between the SW pin and ground. Typical values are 10 W ...
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IN(RMS) Where D is the Duty Cycle = t /( forward voltage of the freewheeling diode. Another consideration for the value of the input capacitor is the ability to supply ...
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... The only two absolutes are that the ORDERING INFORMATION Device NCV8881PWR2G †For information on tape and reel specifications, including part orientation and tape sizes, please refer to our Tape and Reel Packaging Specifications Brochure, BRD8011/D. 1 ...
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... DIMENSIONS: INCHES *For additional information on our Pb−Free strategy and soldering details, please download the ON Semiconductor Soldering and Mounting Techniques Reference Manual, SOLDERRM/D. N. American Technical Support: 800−282−9855 Toll Free USA/Canada Europe, Middle East and Africa Technical Support: ...