Overview
The NCP1052ST136T3G, produced by onsemi, is a highly integrated power management IC designed for high-voltage flyback converters. This device is part of the NCP105X series, which offers a comprehensive solution for modern consumer electronic power supplies. It integrates all the necessary active power, control, logic, and protection circuitry on a single monolithic chip, making it ideal for applications requiring minimal external components and low standby power consumption.
The NCP1052ST136T3G operates directly from a rectified 240 VAC line source and features an active startup regulator circuit, eliminating the need for an auxiliary bias winding on the converter transformer. It also includes fault logic with a programmable timer for converter overload protection and a unique gated oscillator configuration for fast loop response.
Key Specifications
Characteristics | Symbol | Min | Typ | Max | Unit |
---|---|---|---|---|---|
Drain Voltage Range | VDS | 0 | - | 700 | V |
Drain Current Peak During Transformer Saturation | IDS(pk) | - | - | 2.0 x Ilim Max | A |
Oscillator Frequency (VCC = 7.5 V, TJ = 25°C) | fOSC(low) | 38 | 87 | 119 | kHz |
Maximum Duty Cycle | D(max) | 74 | 77 | 80 | % |
Power Switch Circuit On-State Resistance (TJ = 25°C) | RDS(on) | - | - | 22 | Ω |
Current Limit Threshold (TJ = 25°C) | Ilim | 279 | - | 321 | mA |
Thermal Shutdown (Junction Temperature Increasing) | Tsd | 140 | - | 160 | °C |
Startup Threshold/VCC Regulation Peak (VCC Increasing) | VCC(on) | 7.0 | - | 8.0 | V |
Key Features
- Startup Circuit Eliminates the Need for Transformer Auxiliary Bias Winding
- Optional Auxiliary Bias Winding Override for Lowest Standby Power Applications
- Converter Output Overload and Open Loop Protection
- Auto Restart Fault Protection
- IC Thermal Fault Protection
- Unique, Dual Edge, Gated Oscillator Configuration for Extremely Fast Loop Response
- Oscillator Frequency Dithering with Controlled Slew Rate Driver for Reduced EMI
- Low Power Consumption Allowing European Blue Angel Compliance
- On-Chip 700 V Power Switch Circuit and Active Startup Circuit
- Rectified AC Line Source Operation from 85 V to 265 V
- Input Undervoltage Lockout with Hysteresis
- Oscillator Frequency Options of 44 kHz, 100 kHz, 136 kHz
Applications
The NCP1052ST136T3G is suitable for various consumer electronic power supply applications, including:
- Cellular phone chargers
- Standby power supplies for personal computers
- Secondary bias supplies for microprocessor keep-alive supplies
- IR detectors
Q & A
- What is the primary function of the NCP1052ST136T3G?
The NCP1052ST136T3G is a highly integrated power management IC designed for high-voltage flyback converters, integrating all necessary active power, control, logic, and protection circuitry.
- What is the operating voltage range for the NCP1052ST136T3G?
The device operates from a rectified 240 VAC line source and can handle input voltages from 85 V to 265 V.
- What are the oscillator frequency options available for the NCP1052ST136T3G?
The oscillator frequency options are 44 kHz, 100 kHz, and 136 kHz.
- How does the NCP1052ST136T3G handle thermal protection?
The device features thermal shutdown with a junction temperature increasing threshold between 140°C and 160°C and hysteresis.
- What is the purpose of the startup circuit in the NCP1052ST136T3G?
The startup circuit eliminates the need for an auxiliary bias winding on the converter transformer and provides active startup regulation.
- How does the NCP1052ST136T3G reduce EMI?
The device uses oscillator frequency dithering with a controlled slew rate driver to reduce EMI.
- What are the key protection features of the NCP1052ST136T3G?
The device includes converter output overload protection, open loop protection, auto restart fault protection, and IC thermal fault protection.
- What is the maximum duty cycle of the NCP1052ST136T3G?
The maximum duty cycle is between 74% and 80%.
- What is the current limit threshold for the NCP1052ST136T3G?
The current limit threshold is between 279 mA and 321 mA at TJ = 25°C.
- Is the NCP1052ST136T3G compliant with European Blue Angel standards?
Yes, the device allows for low power consumption, complying with European Blue Angel standards.