Specifications
| Type | Description |
|---|---|
| Part Number | NCP1028 |
| Manufacturer | Texas Instruments |
| Product Type | LDO Regulator |
| Category | Power Management |
| Package / Case | PDIP-8, Case 626A |
| Component Type | Power_IC |
| Integrated MOSFET breakdown voltage | 700 V; power switch and startup circuit |
| Typical MOSFET on-state resistance | 5.8 ohm; TJ=25°C |
| Operating frequency options | 65 kHz, 100 kHz; fixed-frequency current-mode operation |
| Fixed peak current | 800 mA; typical internal peak current setpoint |
| Maximum output power, 230 VAC | 25 W typical; open-frame, 65 kHz version, RθJA < 75°C/W, TA=50°C |
| Maximum output power, universal input | 15 W typical; 90-265 VAC, open-frame, 65 kHz version, RθJA < 75°C/W, TA=50°C |
| No-load standby input power | 85 mW; 265 VAC input |
| Loaded input power | 715 mW; 500 mW load, 230 VAC input |
| Maximum duty cycle | 80% typical; extended duty-cycle operation |
| VCC external capacitor | 22 uF typical; connected to VCC pin |
| Brown-out latch-off threshold | 4.0 V; external event drives Brown-Out pin above this level |
| Power supply voltage on pins except Drain | -0.3 to 10 V; maximum rating |
| Drain voltage maximum rating | -0.3 to 700 V; Drain pin, BVdss |
| Peak drain current during transformer saturation | 1.8 A; maximum rating |
| Maximum current into VCC clamp | 15 mA; activating 8.7 V active clamp on pin 1 |
| Thermal resistance junction-to-air | 100 °C/W; PDIP7 package |
| Thermal resistance junction-to-air with copper area | 75 °C/W; PDIP7 with 1.0 cm² of 35 um copper area |
| Maximum junction temperature | 150 °C; maximum rating |
| Storage temperature range | -60 to +150 °C; maximum rating |
| ESD capability, HBM | 2.0 kV; all pins except HV |
| ESD capability, Machine Model | 200 V; maximum rating |
| VCC start threshold | 7.9 min, 8.5 typ, 8.9 max V; VCC increasing level where switcher starts operation |
| VCC stop threshold | 6.7 min, 7.2 typ, 7.9 max V; VCC decreasing level where switcher stops operation |
| VCC UVLO hysteresis | 1.2 V typical; between VCCON and VCC(min) |
| VCC clamp offset | 140 min, 200 typ, 300 max mV; offset above VCCON where internal clamp activates |
| Internal latch reset voltage | 4.0 V typical; VCC voltage where internal latch resets |
| Internal IC consumption | 1.4 typ, 1.9 max mA; MOSFET switching at 65 kHz or 100 kHz, VCC=8.0 V |
| MOSFET RDS(on) at 25°C | 5.8 typ, 7.0 max ohm; Id=100 mA, TJ=25°C |
| MOSFET RDS(on) at 125°C | 9.8 typ, 11 max ohm; Id=100 mA, TJ=125°C |
| Power switch breakdown voltage | 700 V min; ID(off)=120 uA, TJ=25°C |
| Off-state leakage current at 25°C | 5 uA typical; VDS=700 V, TJ=25°C |
| Off-state leakage current at 125°C | 30 uA typical; VDS=700 V, TJ=125°C |
| Turn-on time | 35 ns typical; RL=50 ohm, VDS set for Idrain=0.7 x Ilim, 10%-90% |
| Turn-off time | 35 ns typical; RL=50 ohm, VDS set for Idrain=0.7 x Ilim, 90%-10% |
| High-voltage startup current source IC1 | 3.5 min, 6.0 typ, 8.0 max mA; VCC=VCCON - 200 mV |
| High-voltage startup current source IC2 | 350 min, 650 typ, 900 max uA; VCC=0 V |
| Startup current source transition level | 1.3 V typical; VCC transition level for IC1 to IC2 toggling point |
| Maximum internal current setpoint, 65 kHz | 720 min, 800 typ, 880 max mA; Pin 4 open, TJ=25°C, FSW=65 kHz |
| Final switch current, 65 kHz | 820 mA typical; Primary slope=200 mA/us, FSW=65 kHz |
| Maximum internal current setpoint, 100 kHz | 720 min, 800 typ, 880 max mA; Pin 4 open, TJ=25°C, FSW=100 kHz |
| Final switch current, 100 kHz | 820 mA typical; Primary slope=200 mA/us, FSW=100 kHz |
| OPP setpoint decrease | 23% typical; Pin 7 injected current=40 uA, TJ=25°C |
| OPP start voltage | 1.5 V typical; Pin 7 voltage where OPP starts operating |
| Soft-start duration | 1.0 ms typical; current comparator section |
| Current detection propagation delay | 100 ns typical; from current detection to Drain off-state |
| Leading edge blanking duration | 200 ns typical; current comparator section |
| Oscillation frequency, 65 kHz version | 58.5 min, 65 typ, 71.5 max kHz; TJ=25°C, jittering disabled |
| Oscillation frequency, 100 kHz version | 90 min, 100 typ, 110 max kHz; TJ=25°C, jittering disabled |
| Frequency jittering | +/-6.0% typical; percentage of fOSC |
| Jittering swing frequency | 300 Hz typical; internal oscillator |
| Maximum duty cycle electrical range | 74 min, 80 typ, 87 max %; internal oscillator section |
| Feedback pullup resistor | 16 kOhm typical; Pin 4 internal pullup resistor |
| Ramp compensation level | 2.75 V typical; Pin 1, Rramp=100 kOhm |
| Skip mode level | 25% typical; percentage of maximum peak current |
| Brown-out level | 510 min, 570 typ, 620 max mV; Pin 3 brown-out protection |
| Brown-out hysteresis current at 25°C | 10 min, 11.5 typ, 13 max uA; TJ=25°C |
| Brown-out hysteresis current over temperature | 10 uA typical; TJ=0°C to 125°C |
| Fault validation timer | 40 min, 55 typ ms; further to error flag assertion |
| Fault mode off phase | 440 ms typical; OFF phase in fault mode |
| Brown-out pin latching voltage | 3.15 min, 3.5 typ, 3.85 max V; Pin 3 latch input |
| Latch input filter time constant | 20 us typical; Brown-out latch input integrating filter |
| Temperature shutdown | 160 °C min; temperature management |
| Thermal shutdown hysteresis | 40 °C typical; temperature management |
| Datasheet Status | request_only |
Product Overview
NCP1028 is a Texas Instruments high-voltage offline SMPS switcher categorized under Power_Management. The device integrates a 700 V power switch and startup circuit, supporting fixed-frequency current-mode operation with 65 kHz and 100 kHz frequency options. The internal current setpoint is 800 mA typical, with a specified final switch current of 820 mA typical under a 200 mA/us primary slope condition.
The part is supplied in a PDIP-8, Case 626A package. Thermal data includes 100°C/W junction-to-air thermal resistance for the PDIP7 package, improved to 75°C/W with 1.0 cm² of 35 um copper area. Maximum ratings include -0.3 to 700 V on the Drain pin, 150°C maximum junction temperature, and -60 to +150°C storage temperature.
Power supply behavior is defined by an 8.5 V typical VCC start threshold, 7.2 V typical stop threshold, and 1.2 V typical UVLO hysteresis. Protection and control functions include brown-out detection, latch input filtering, soft start, current detection blanking, frequency jittering, skip mode operation, and thermal shutdown.
Key Features
- Integrated 700 V MOSFET and startup circuit
- 5.8 ohm typical MOSFET RDS(on) at 25°C
- 65 kHz and 100 kHz fixed-frequency options
- 800 mA typical internal peak current setpoint
- 80% typical maximum duty-cycle operation
- 85 mW no-load standby input power at 265 VAC
- 1.0 ms typical soft-start duration
- +/-6.0% typical oscillator frequency jittering
- Brown-out protection with 570 mV typical level
- 160°C minimum temperature shutdown threshold
Typical Applications
- Offline SMPS power supplies
- Universal 90-265 VAC input supplies
- 230 VAC open-frame power supplies
- Low standby input power designs
- Fixed-frequency current-mode converters
- Supplies requiring brown-out protection
- Thermally monitored power switchers
Procurement Notes
When requesting a quote for NCP1028, buyers should confirm the manufacturer, package or case, required quantity, target date code, compliance documents, packing method, destination country and expected delivery schedule.
If alternatives are acceptable, buyers should share the approved vendor list, required electrical or optical limits, package constraints and qualification requirements. Any alternative part should be reviewed by the buyer's engineering team before production use.
For power IC and power device sourcing, voltage rating, current rating, power dissipation, package thermal performance, protection features, qualification grade and application conditions should be reviewed before approval.
FAQ
What type of power IC is the NCP1028?
The NCP1028 is described as a high-voltage offline SMPS switcher in the Power_Management category. It integrates a 700 V power switch and startup circuit and operates as a fixed-frequency current-mode device.
Which switching frequency options are specified for NCP1028?
The extracted datasheet facts list 65 kHz and 100 kHz fixed-frequency current-mode operating options. The 65 kHz version is specified at 58.5 kHz minimum, 65 kHz typical, and 71.5 kHz maximum with jittering disabled.
What package is listed for the NCP1028?
The package case provided for NCP1028 is PDIP-8, Case 626A. Thermal data also lists PDIP7 junction-to-air values of 100°C/W and 75°C/W when used with 1.0 cm² of 35 um copper area.
What are the key current and MOSFET ratings?
The NCP1028 has an 800 mA typical internal peak current setpoint and a 700 V minimum power switch breakdown rating. MOSFET RDS(on) is specified as 5.8 ohm typical and 7.0 ohm maximum at 25°C.
What standby input power is specified for this device?
The extracted facts specify 85 mW no-load standby input power at 265 VAC. A loaded input power value of 715 mW is also listed for a 500 mW load with 230 VAC input.
Technical Review & Sourcing Note
Prepared by LDeepAI Component Sourcing Team. Reviewed for RFQ, documentation and alternative sourcing use. Last updated: July 26, 2026.
This page is based on manufacturer datasheet information and LDeepAI sourcing review. Specifications should be verified against the official manufacturer datasheet before final procurement or design approval. Final electrical, optical and reliability approval should be confirmed by the buyer's engineering team.