Overview
The NCP1203D40R2G, produced by onsemi, is a PWM Current-Mode Controller designed for universal off-line power supplies. It is housed in an SOIC-8 package and is a significant advancement in ultra-compact switch-mode power supplies. This controller is an excellent replacement for UC384X devices, leveraging onsemi's proprietary SMARTMOS Very High Voltage Technology. It enables the implementation of complete off-line AC-DC adapters, battery chargers, and high-power SMPS with minimal external components. The NCP1203 operates at a fixed switching frequency of 40 kHz, 60 kHz, or 100 kHz, depending on the version, and features a high-voltage startup FET for a clean and lossless startup sequence.
Key Specifications
| Characteristic | Symbol | Min | Typ | Max | Unit |
|---|---|---|---|---|---|
| Turn-on Threshold Level, VCC Going Up | VCC(on) | 12.2 | 12.8 | 14 | V |
| Minimum Operating Voltage after Turn-on | VCC(min) | 7.2 | 7.8 | 8.4 | V |
| Internal IC Consumption, No Output Load on Pin 5 | ICC1 | - | 750 | 880 | μA |
| Internal IC Consumption, 1.0 nF Output Load on Pin 5, FSW = 40 kHz | ICC2 | - | 1.2 | 1.4 | mA |
| Oscillation Frequency (40 kHz Version) | fOSC | 37 | 42 | 47 | kHz |
| Maximum Duty-Cycle | Dmax | 74 | 80 | 87 | % |
| Peak Current Capability | - | - | 250 | - | mA |
Key Features
- High-Voltage Startup Current Source
- Auto-Recovery Internal Output Short-Circuit Protection
- Extremely Low No-Load Standby Power
- Current-Mode with Adjustable Skip-Cycle Capability
- Internal Leading Edge Blanking
- Internally Fixed Frequency at 40 kHz, 60 kHz, and 100 kHz
- Direct Optocoupler Connection
- Undervoltage Lockout at 7.8 V Typical
- SPICE Models Available for Transient and AC Analysis
- Pin to Pin Compatible with NCP1200
- Pb-Free, Halogen Free/BFR Free and RoHS Compliant
Applications
- AC-DC Adapters for Notebooks, etc.
- Offline Battery Chargers
- Auxiliary Power Supplies (USB, Appliances, TVs, etc.)
Q & A
- What is the NCP1203D40R2G used for?
The NCP1203D40R2G is used for implementing universal off-line power supplies, including AC-DC adapters, battery chargers, and high-power SMPS.
- What is the switching frequency of the NCP1203D40R2G?
The NCP1203D40R2G operates at a fixed switching frequency of 40 kHz.
- What is the peak current capability of the NCP1203D40R2G?
The peak current capability of the NCP1203D40R2G is 250 mA.
- Does the NCP1203D40R2G have short-circuit protection?
Yes, the NCP1203D40R2G features auto-recovery internal output short-circuit protection.
- What is the minimum operating voltage after turn-on for the NCP1203D40R2G?
The minimum operating voltage after turn-on is typically 7.8 V.
- Is the NCP1203D40R2G RoHS compliant?
Yes, the NCP1203D40R2G is Pb-Free, Halogen Free/BFR Free and RoHS compliant.
- What is the purpose of the high-voltage startup FET in the NCP1203D40R2G?
The high-voltage startup FET ensures a clean and lossless startup sequence by injecting a constant current into the VCC capacitor during startup.
- How does the skip cycle feature work in the NCP1203D40R2G?
The skip cycle feature allows the controller to skip unwanted switching cycles at low power levels, reducing standby power and ensuring quiet operation.
- What is the maximum duty-cycle of the NCP1203D40R2G?
The maximum duty-cycle is 80%.
- Does the NCP1203D40R2G support direct optocoupler connection?
Yes, the NCP1203D40R2G supports direct optocoupler connection.
