Overview
The NCP1246BD065R2G is a fixed-frequency current-mode controller produced by onsemi. This device is designed for use in flyback converters and features the Dynamic Self-Supply function, which simplifies the design of the auxiliary supply and VCC capacitor by activating an internal startup current source during start-up, transients, and standby conditions. It includes a high-voltage detector that detects application unplug from the AC input line and triggers the X2 discharge current, along with brown-out detection circuitry. The controller also features timer-based fault detection for overload protection and adjustable power compensation to maintain maximum power independent of the input voltage.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Operating Frequency | 65 kHz | - |
| Maximum Duty Cycle | Up to 50% | - |
| VCC Power Supply Voltage | -0.3 to 28 V | V |
| Maximum Voltage on DRV Pin | -0.3 to 20 V | V |
| Maximum Voltage on HV Pin | -0.3 to 500 V | V |
| Drive Output Peak Current Capability | 500/800 mA | mA |
| Soft-Start Time | 10 ms (AL/BL Versions: 4 ms) | ms |
| No-Load Standby Power | < 30 mW | mW |
| Internal Thermal Shutdown | Yes | - |
| X2 Capacitor Discharging Feature | Yes | - |
Key Features
- Fixed-Frequency Current-Mode Operation (65 kHz and 100 kHz frequency options)
- Frequency Foldback then Skip Mode for maximized performance in light load and standby conditions
- Timer-Based Overload Protection with Latched (Option A) or Auto-Recovery (Option B) Operation
- High-Voltage Current Source with Brown-Out Detection and Dynamic Self-Supply
- Frequency Modulation for softened EMI signature
- Adjustable Overpower Protection dependent on the bulk voltage
- Latch-Off Input combined with the Overpower Protection Sensing Input
- VCC Operation up to 28 V, with Overvoltage Detection
- Internal Thermal Shutdown
- No-Load Standby Power < 30 mW
- X2 Capacitor in EMI Filter Discharging Feature
- Pb-Free, Halogen Free/BFR Free and RoHS Compliant
Applications
- AC-DC Adapters for Notebooks, LCD, and Printers
- Offline Battery Chargers
- Consumer Electronic Power Supplies
- Auxiliary/Housekeeping Power Supplies
- Offline Adapters for Notebooks
Q & A
- What is the primary function of the NCP1246BD065R2G?
The NCP1246BD065R2G is a fixed-frequency current-mode controller designed for use in flyback converters, featuring Dynamic Self-Supply and various protection mechanisms.
- What are the available operating frequencies for the NCP1246BD065R2G?
The device operates at 65 kHz and 100 kHz frequencies.
- What is the maximum duty cycle of the NCP1246BD065R2G?
The maximum duty cycle can be up to 50%.
- What is the VCC power supply voltage range for the NCP1246BD065R2G?
The VCC power supply voltage range is from -0.3 to 28 V.
- What is the maximum voltage on the DRV pin?
The maximum voltage on the DRV pin is -0.3 to 20 V.
- Does the NCP1246BD065R2G have internal thermal shutdown protection?
Yes, it does have internal thermal shutdown protection.
- What is the no-load standby power consumption of the NCP1246BD065R2G?
The no-load standby power consumption is less than 30 mW.
- Is the NCP1246BD065R2G RoHS compliant?
Yes, the device is Pb-Free, Halogen Free/BFR Free and RoHS Compliant.
- What are some typical applications of the NCP1246BD065R2G?
Typical applications include AC-DC adapters for notebooks, LCD, and printers, offline battery chargers, consumer electronic power supplies, and auxiliary/housekeeping power supplies.
- How does the Dynamic Self-Supply function work in the NCP1246BD065R2G?
The Dynamic Self-Supply function activates an internal startup current source to supply the controller during start-up, transients, and standby conditions, simplifying the design of the auxiliary supply and VCC capacitor.
