Overview
The NCP1015ST100T3G, produced by onsemi, is a self-supplied monolithic switcher designed for low standby power offline Switch-Mode Power Supplies (SMPS). This integrated circuit combines a fixed-frequency current-mode controller with a 700 V voltage MOSFET, making it an ideal solution for building rugged and low-cost power supplies. The NCP1015 is available in PDIP-7 and SOT-223 packages, offering features such as soft-start, frequency jittering, short-circuit protection, and skip-cycle operation to enhance efficiency and reduce noise.
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| VCC(off) | 7.9 | 8.5 | 9.1 | V |
| VCC(on) | 6.9 | 7.5 | 8.1 | V |
| VCCLATCH | 4.4 | 4.7 | 5.1 | V |
| ICC1 (65 kHz) | - | 0.92 | 1.1 | mA |
| ICC1 (100 kHz) | - | 0.95 | 1.15 | mA |
| Ipeak | 405 | 450 | 495 | mA |
| fOSC (65 kHz version) | 59 | 65 | 71 | kHz |
| fOSC (100 kHz version) | 90 | 100 | 110 | kHz |
| TSD | 150 | - | - | °C |
| RDS(on) | - | 11 Ω | - | Ω |
Key Features
- Built-in 700 V MOSFET with typical RDS(on) of 11 Ω
- Large Creepage Distance between High-voltage Pins
- Current-mode Fixed Frequency Operation: 65 kHz - 100 kHz
- Skip-cycle Operation at Low Peak Currents Only: No Acoustic Noise!
- Dynamic Self-Supply, No Need for an Auxiliary Winding
- Internal 1 ms Soft-start
- Auto-recovery Internal Output Short-circuit Protection
- Frequency Jittering for Better EMI Signature
- Below 100 mW Standby Power if Auxiliary Winding is Used
- Internal Temperature Shutdown
- Direct Optocoupler Connection
- SPICE Models Available for Transient and AC Analysis
Applications
The NCP1015 is designed for use in various offline Switch-Mode Power Supplies (SMPS) requiring low standby power. It is particularly suitable for applications such as:
- Universal power supplies
- Consumer electronics power supplies
- Industrial power supplies
- LED drivers and lighting systems
- Other low-power SMPS applications where efficiency and low noise are critical
Q & A
- What is the typical RDS(on) of the MOSFET in the NCP1015?
The typical RDS(on) of the MOSFET in the NCP1015 is 11 Ω.
- What are the operating frequency ranges of the NCP1015?
The NCP1015 operates at fixed frequencies between 65 kHz and 100 kHz.
- How does the NCP1015 reduce standby power?
The NCP1015 reduces standby power by skipping unnecessary switching cycles at low peak currents and using an auxiliary winding to disable the Dynamic Self-Supply (DSS) operation if needed.
- What is the purpose of the Dynamic Self-Supply (DSS) feature?
The DSS feature allows the IC to be supplied directly from the high-voltage DC rail, simplifying transformer design and improving control in difficult output conditions.
- How does the NCP1015 protect against short-circuits?
The NCP1015 detects short-circuits by monitoring the feedback line activity and immediately reduces output power to protect the system. It also features auto-recovery from short-circuit conditions.
- What is the significance of the skip-cycle operation in the NCP1015?
The skip-cycle operation ensures that the IC skips switching cycles at low peak currents, reducing power waste and eliminating acoustic noise.
- Does the NCP1015 generate acoustic noise during operation?
No, the NCP1015 does not generate acoustic noise due to its skip-cycle operation at low peak currents.
- What is the internal temperature shutdown threshold of the NCP1015?
The internal temperature shutdown threshold of the NCP1015 is 150°C.
- Is there a soft-start feature in the NCP1015?
Yes, the NCP1015 features an internal 1 ms soft-start activated during power-on sequences and overcurrent conditions.
- Are SPICE models available for the NCP1015?
Yes, SPICE models are available for transient and AC analysis of the NCP1015.
