Overview
The NCP1200D60R2G, produced by onsemi, is a PWM current-mode controller designed for low-power universal offline power supplies. It is housed in an SO-8 package and represents a significant advancement in ultra-compact switch-mode power supplies. This controller enables the implementation of complete offline battery chargers or standby SMPS with minimal external components. It features an integrated output short-circuit protection, allowing for the design of low-cost AC-DC wall adapters with simplified feedback schemes. The NCP1200 operates at fixed frequencies of 40 kHz, 60 kHz, or 100 kHz and drives low gate-charge switching devices like IGBTs or MOSFETs, requiring very small operating power.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Package Type | SOIC-8 | |
| Switching Frequency | 60 kHz | |
| Control Mode | Current Mode | |
| Peak Current Source/Sink Capability | 250 mA | |
| Internal Temperature Shutdown | 150°C | °C |
| Maximum Duty Cycle | 74-87% | % |
| VCC Increasing Level at Which the Current Source Turns-off | 10.3-12.5 V | V |
| VCC Decreasing Level at Which the Current Source Turns-on | 8.8-11 V | V |
| Internal IC Consumption (No Output Load) | 710-880 μA | μA |
| High-Voltage Current Source (VCC = 10 V) | 2.8-4.0 mA | mA |
Key Features
- No Auxiliary Winding Operation: Self-supplied from the DC rail, eliminating the need for an auxiliary winding.
- Internal Output Short-Circuit Protection: Ensures safe operation and prevents damage from short circuits.
- Extremely Low No-Load Standby Power: Optimized for low power consumption in standby mode.
- Current-Mode with Skip-Cycle Capability: Automatically enters skip cycle mode at light loads for excellent efficiency and reduced acoustic noise.
- Internal Leading Edge Blanking: Reduces noise and improves reliability.
- 250 mA Peak Current Source/Sink Capability: Supports high current requirements.
- Internally Fixed Frequency at 40 kHz, 60 kHz, and 100 kHz: Provides flexibility in design and operation.
- Direct Optocoupler Connection: Simplifies feedback loop design.
- Built-in Frequency Jittering for Lower EMI: Reduces electromagnetic interference.
- SPICE Models Available for Transient and AC Analysis: Facilitates detailed simulation and analysis.
- Internal Temperature Shutdown: Protects the IC from overheating.
- Pb-Free, Halogen Free/BFR Free, and RoHS Compliant: Meets environmental and safety standards.
Applications
- AC-DC Adapters: Ideal for compact and efficient power adapters.
- Offline Battery Chargers: Suitable for charging batteries in offline configurations.
- Auxiliary/Ancillary Power Supplies: Used in various applications such as USB power supplies, appliances, and TVs.
Q & A
- What is the primary function of the NCP1200D60R2G?
The NCP1200D60R2G is a PWM current-mode controller designed for low-power universal offline power supplies.
- What are the available switching frequencies for the NCP1200D60R2G?
The NCP1200D60R2G operates at fixed frequencies of 40 kHz, 60 kHz, or 100 kHz.
- What is the significance of the Dynamic Self-Supply (DSS) feature?
The DSS feature allows the IC to be self-supplied from the DC rail, eliminating the need for an auxiliary winding.
- How does the skip cycle mode improve efficiency?
The skip cycle mode automatically engages at light loads, providing excellent efficiency and reducing acoustic noise.
- What protection features does the NCP1200D60R2G include?
The IC includes internal output short-circuit protection and internal temperature shutdown.
- What is the maximum duty cycle of the NCP1200D60R2G?
The maximum duty cycle is between 74% and 87%.
- Is the NCP1200D60R2G environmentally compliant?
Yes, it is Pb-Free, Halogen Free/BFR Free, and RoHS Compliant.
- What are the typical applications of the NCP1200D60R2G?
Typical applications include AC-DC adapters, offline battery chargers, and auxiliary power supplies.
- What is the peak current source/sink capability of the NCP1200D60R2G?
The peak current source/sink capability is 250 mA.
- Does the NCP1200D60R2G support SPICE models for analysis?
Yes, SPICE models are available for transient and AC analysis.
