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Contents

README

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NCP1031DR2G

onsemi · AC-DC Controllers And Regulators · SOIC-8

NCP1031DR2G from onsemi, in a SOIC-8. Pinout and pin descriptions extracted from the manufacturer datasheet (extract_pins, cross-checked by a second model); symbol, footprint, and 3D from KiCad-official CAD.

Pinout

Pin Name Type Function
1 GND power_in Ground reference pin for the circuit.
2 CT passive An external capacitor connected to this pin sets the oscillator frequency up to 1 MHz, and the frequency is reduced by a factor of 7 when a fault condition exists.
3 VFB input The regulated output voltage is scaled down to 2.5 V by a resistor divider and compared to an internal 2.5 V reference.
4 COMP passive Requires an external compensation network between COMP and VFB, and is effectively grounded when faults are present.
5 OV input Line voltage is scaled down by an external resistor divider so that OV reaches 2.5 V at the maximum operating line voltage.
6 UV input Line voltage is scaled down by an external resistor divider so that UV reaches 2.5 V at the minimum operating line voltage.
7 VCC power_in Connected to an external energy storage capacitor; the startup circuit charges it at turn-on and VCC should not exceed 16 V.
8 VDRAIN passive Connects the power switch and startup circuits directly to one transformer winding; VDRAIN should not exceed 200 V.

Key specifications

Parameter Value
Manufacturer onsemi
Package SOIC-8
Category Power Management (PMIC)
Pins 8

Electrical characteristics

Limits as printed in the datasheet (page.json metadata.characteristics carries them as data).

Parameter Symbol Min Typ Max Unit Conditions Page
Power Switch and Startup Circuits Voltage VDRAIN -0.3 200 V 4
Power Switch and Startup Circuits Input Current (NCP1031) IDRAIN 2 A 4
VCC Voltage Range VCC -0.3 16 V 4
All Other Inputs/Outputs Voltage Range VIO -0.3 10 V 4
VCC and All Other Inputs/Outputs Current IIO 100 mA 4
Operating Junction Temperature TJ -40 150 °C 4
Storage Temperature Tstg -55 150 °C 4
Power Dissipation, D Suffix Plastic Package Case 751 (SOIC-8) 0.893 W TJ = 25°C, 2.0 Oz., 1.0 Sq Inch Printed Circuit Copper Clad 4
Thermal Resistance, Junction to Air, D Suffix Case 751 RJA 112 °C/W 2.0 Oz., 1.0 Sq Inch Printed Circuit Copper Clad 4
ESD Human Body Model, pins 1-7 2000 V Pins 1-7, per MIL-STD-883 Method 3015 4
ESD Machine Model, pins 1-7 200 V Pins 1-7, Machine Model Method 4
Startup Threshold Voltage (VCC Increasing) VCC(on) 9.6 10.2 10.6 V VFB = 2.7 V 5
Minimum Operating VCC After Turn-on (VCC Decreasing) VCC(off) 7 7.6 8 V VFB = 2.7 V 5
Undervoltage Lockout Threshold Voltage, VCC Decreasing VCC(reset) 6 6.6 7 V VFB = VCOMP 5
Minimum Startup Voltage (Pin 8) VSTART(min) 16.8 18.5 V ISTART = 0.5 mA, VCC = VCC(on) − 0.2 V 5
Reference Voltage (Follower Mode) VREF 2.45 2.5 2.55 V VCOMP = VFB, TJ = 25°C 5
Reference Voltage (Follower Mode) VREF 2.4 2.5 2.6 V VCOMP = VFB, TJ = −40°C to 125°C 5
Line Regulation REGLINE 1 5 mV VCC = 8 V to 16 V, TJ = 25°C 5
Input Bias Current IVFB 0.1 1 µA VFB = 2.3 V 5
COMP Source Current ISRC 80 110 140 µA 5
COMP Sink Current ISNK 200 550 900 µA VFB = 2.7 V 5
COMP Maximum Voltage VC(max) 4.5 V ISRC = 0 A 5
COMP Minimum Voltage VC(min) 1 V ISNK = 0 A, VFB = 2.7 V 5
Undervoltage Lockout Voltage Threshold (Vin Increasing) VUV 2.4 2.55 2.7 V VFB = VCOMP 5
Undervoltage Voltage Hysteresis VUV(hys) 0.075 0.175 0.275 V VFB = VCOMP 5
Undervoltage Input Bias Current IUV 0 1 µA VFB = VCOMP 5
Overvoltage Lockout Voltage Threshold (Vin Increasing) VOV 2.4 2.55 2.7 V VFB = VCOMP 5
Overvoltage Voltage Hysteresis VOV(hys) 0.075 0.175 0.275 V VFB = VCOMP 5
Overvoltage Input Bias Current IOV 0 1 µA VFB = VCOMP 5
Oscillator Frequency fOSC1 275 300 kHz CT = 560 pF, TJ = 25°C 6
Oscillator Frequency fOSC1 260 325 kHz CT = 560 pF, TJ = −40°C to 125°C 6
Oscillator Ramp Valley Vrvly 3 V 6
Oscillator Ramp Peak Vrpk 3.5 V 6
Maximum Duty Cycle DCMAX 70 75 80 % 6
Power Switch Circuit On-State Resistance (NCP1031) RDS(on) 2.1 3 Ω ID = 100 mA, TJ = 25°C 6
Power Switch Circuit On-State Resistance (NCP1031) RDS(on) 3.5 6 Ω ID = 100 mA, TJ = 125°C 6
Power Switch and Startup Circuit Breakdown Voltage V(BR)DS 200 V ID = 100 µA, TJ = 25°C 6
Power Switch and Startup Circuit Off-State Leakage Current IDS(off) 50 µA VDRAIN = 200 V, VUV = 2.0 V, TJ = −40 to 125°C 6
Current Limit Threshold (NCP1031) ILIM 700 1050 1360 mA TJ = 25°C, di/dt = 1.0 A/µs 6
Supply Current After UV Turn-On, Power Switch Enabled ICC1 2 3 4 mA Non-fault condition (VFB = 2.7 V) 6
Supply Current After UV Turn-On, Power Switch Disabled ICC2 1.5 2 mA Power Switch Disabled 6
Supply Current After UV Turn-On, Fault Condition ICC3 0.65 1.2 mA Fault Condition (VFB = 2.7 V, VUV = 2.0 V) 6

CAD (KiCad official)

  • Symbol: NCP1031DR2G
  • Footprint: Package_SO:SOIC-8_3.9x4.9mm_P1.27mm
  • 3D model: SOIC-8 (KiCad packages3D, STEP)
  • 3D model files: ncp1031dr2g-etched.step / ncp1031dr2g-etched.glb carry the MPN laser-etched on the die in a toggleable Adom.LaserEtch group (Fusion-ready); ncp1031dr2g.step / ncp1031dr2g.glb are the bare package body.

Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

  • Datasheet: onsemi datasheet (21 pp, sha256 9d1c98817b6525b0, retrieved 2026-10-20, tier: lcsc)
  • Extractor: parts-factory 2.0.0 / extract_pins 0.3, primary claude-haiku-5-5 (text), consensus claude-sonnet-5-5 (agreed), guards: pin_guards 0.1: passed. Pins are checked against the footprint pad set and their cited datasheet pages before publish.
  • CAD: KiCad official libraries (CC-BY-SA 4.0).

Datasheet PDF