Overview
The NCP1200P100G, produced by onsemi, is a PWM Current-Mode Controller designed for low-power universal off-line supplies. This component is housed in either an SOIC-8 or PDIP-8 package and represents a significant advancement in ultra-compact switchmode power supplies. The NCP1200 integrates all necessary components for a complete offline battery charger or standby SMPS, including timing components, feedback devices, and a self-supply mechanism, eliminating the need for an auxiliary winding. This controller operates at fixed frequencies of 40 kHz, 60 kHz, or 100 kHz and is ideal for applications requiring low part-count and high efficiency.
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| VCC Increasing Level at Which the Current Source Turns-off (VCCOFF) | 10.3 | 11.4 | 12.5 | V |
| VCC Decreasing Level at Which the Current Source Turns-on (VCCON) | 8.8 | 9.8 | 11 | V |
| Internal IC Consumption, No Output Load on Pin 5 (ICC1) | - | 710 | 880 | μA |
| Internal IC Consumption, 1 nF Output Load on Pin 5, FSW = 100 kHz (ICC2) | - | 1.9 | 2.2 | mA |
| Oscillation Frequency, 100 kHz Version (fOSC) | 86 | 103 | 116 | kHz |
| Maximum Duty Cycle (Dmax) | 74 | 80 | 87 | % |
| Peak Current Source/Sink Capability | - | 250 | - | mA |
Key Features
- No Auxiliary Winding Operation
- Internal Output Short-Circuit Protection
- Extremely Low No-Load Standby Power
- Current-Mode with Skip-Cycle Capability
- Internal Leading Edge Blanking
- Internally Fixed Frequency at 40 kHz, 60 kHz, and 100 kHz
- Direct Optocoupler Connection
- Built-in Frequency Jittering for Lower EMI
- SPICE Models Available for Transient and AC Analysis
- Internal Temperature Shutdown
- Pb-Free, Halogen Free/BFR Free, and RoHS Compliant
Applications
- AC-DC Adapters
- Offline Battery Chargers
- Auxiliary/Ancillary Power Supplies (USB, Appliances, TVs, etc.)
Q & A
- What is the NCP1200P100G used for? The NCP1200P100G is used for low-power universal off-line supplies, including AC-DC adapters and offline battery chargers.
- What are the available operating frequencies for the NCP1200P100G? The NCP1200P100G operates at fixed frequencies of 40 kHz, 60 kHz, or 100 kHz.
- Does the NCP1200P100G require an auxiliary winding? No, the NCP1200P100G does not require an auxiliary winding due to its Dynamic Self-Supply (DSS) mechanism.
- What is the Dynamic Self-Supply (DSS) principle? The DSS principle involves the charge/discharge of the VCC bulk capacitor from a low level to a higher level, eliminating the need for an auxiliary winding.
- How does the skip cycle mode work in the NCP1200P100G? The skip cycle mode is activated when the output power demand drops below a certain level, causing the IC to blank output pulses and enter a controlled burst operation to maintain efficiency at light loads.
- What is the maximum duty cycle of the NCP1200P100G? The maximum duty cycle is between 74% and 87%.
- Is the NCP1200P100G environmentally friendly? Yes, the NCP1200P100G is Pb-Free, Halogen Free/BFR Free, and RoHS Compliant.
- What is the peak current source/sink capability of the NCP1200P100G? The peak current source/sink capability is 250 mA.
- How does the built-in frequency jittering feature help? The built-in frequency jittering helps in reducing EMI (Electromagnetic Interference).
- Are SPICE models available for the NCP1200P100G? Yes, SPICE models are available for transient and AC analysis.
