Overview
The NCP1200AP100, produced by onsemi, is a PWM Current-Mode Controller designed for low-power universal off-line power supplies. It significantly simplifies the design of reliable and cost-effective offline converters, offering excellent audio susceptibility and inherent pulse-by-pulse control. Housed in SO-8 or DIP-8 packages, this controller is ideal for ultra-compact switch-mode power supplies, including offline battery chargers and standby SMPS with minimal external components.
The NCP1200AP100 operates at fixed frequencies of 40 kHz, 60 kHz, or 100 kHz and drives low gate-charge switching devices such as IGBTs or MOSFETs, requiring very small operating power. It features an internal structure that automatically enters skip cycle mode at light loads, ensuring high efficiency and eliminating acoustic noise.
The controller is self-supplied from the DC rail, eliminating the need for an auxiliary winding, and includes integrated output short-circuit protection and extremely low no-load standby power.
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| Operating Frequency | 36 (40 kHz version) | 42 (40 kHz version) | 48 (40 kHz version) | kHz |
| Operating Frequency | 52 (60 kHz version) | 61 (60 kHz version) | 70 (60 kHz version) | kHz |
| Operating Frequency | 86 (100 kHz version) | 103 (100 kHz version) | 116 (100 kHz version) | kHz |
| VCC Increasing Level at Which the Current Source Turns-off | 10.3 | 11.4 | 12.5 | V |
| VCC Decreasing Level at Which the Current Source Turns-on | 8.8 | 9.8 | 11 | V |
| Internal IC Consumption, No Output Load on Pin 5 | 710 | 880 | - | μA |
| Peak Current Source/Sink Capability | - | 250 | - | mA |
| Maximum Duty Cycle | 74 | 80 | 87 | % |
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 robust operation against output short circuits.
- Extremely Low No-Load Standby Power: Minimizes power consumption during standby mode.
- Current-Mode with Skip-Cycle Capability: Automatically enters skip cycle mode at light loads for high efficiency and no acoustic noise.
- Internal Leading Edge Blanking: Reduces noise and improves stability.
- 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.
- 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: Ensures safe operation by shutting down at high temperatures.
- 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: Simplifies the design of battery charging systems.
- Auxiliary/Ancillary Power Supplies: Suitable for USB, appliances, TVs, and other auxiliary power needs.
Q & A
- What is the NCP1200AP100 used for?
The NCP1200AP100 is used for designing reliable and cost-effective offline power supplies, including AC-DC adapters, offline battery chargers, and auxiliary power supplies.
- What are the operating frequencies of the NCP1200AP100?
The NCP1200AP100 operates at fixed frequencies of 40 kHz, 60 kHz, or 100 kHz.
- Does the NCP1200AP100 require an auxiliary winding?
No, the NCP1200AP100 is self-supplied from the DC rail, eliminating the need for an auxiliary winding.
- What is the skip cycle mode in the NCP1200AP100?
The skip cycle mode is activated when the output power demand drops below a certain level, ensuring high efficiency and eliminating acoustic noise at light loads.
- What kind of protection does the NCP1200AP100 offer?
The NCP1200AP100 offers internal output short-circuit protection and overload detection circuitry to handle fault conditions.
- Is the NCP1200AP100 environmentally compliant?
- What is the maximum duty cycle of the NCP1200AP100?
The maximum duty cycle of the NCP1200AP100 is between 74% and 87%.
- How does the NCP1200AP100 reduce EMI?
The NCP1200AP100 features built-in frequency jittering to reduce electromagnetic interference (EMI).
- Are SPICE models available for the NCP1200AP100?
- What is the internal temperature shutdown feature of the NCP1200AP100?
The NCP1200AP100 has an internal temperature shutdown feature that ensures safe operation by shutting down the IC at high temperatures.
