onsemi NCP1239 Switching Controllers
onsemi NCP1239 Switching Controllers are fixed-frequency current-mode controllers featuring a high-voltage start-up current source to provide a quick and lossless power-on sequence. This function greatly simplifies the design of the auxiliary supply and the VCC capacitor. These NCP1239 controllers feature a timer-based fault detection circuitry that ensures a quasi-flat overload detection, independent of the input voltage. Typical applications include AC-DC converters for TVs, set-top boxes, and printers offline adapters for notebooks and netbooks.Features
- Fixed-frequency 65kHz or 100kHz current-mode control operation
- Frequency foldback down to 26kHz and skip mode to maximize performance in light load conditions
- Adjustable Over Power Protection (OPP) circuit
- High-voltage current source with Brown-Out (BO) detection
- Internal slope compensation
- Internal fixed soft-start
- Frequency jittering in normal and frequency foldback modes
- 64ms timer-based short-circuit protection with auto-recovery or latched operation
- Pre-short ready for latched OCP versions
- Latched OVP on VCC auto-recovery for C and E versions
- Latched OVP/OTP input for improved robustness
- 35V VCC operation
- ±500mA peak source/sink drive capability
- Internal thermal shutdown
- Extremely low no-load standby power
- Pin-to-pin compatible with the existing NCP1236/1247 series
- These devices are Pb-free and are RoHS compliant
Applications
- AC-DC converters for TVs, set-top boxes, and printers
- Offline adapters for notebooks and netbooks
NCP1239 Block Diagram
發佈日期: 2018-07-10
| 更新日期: 2022-10-31
