Overview
The NCP1216D65R2G, produced by ON Semiconductor, is a PWM Current-Mode Controller designed for high-power universal off-line supplies. This controller is an enhanced version of the NCP1200 series and is housed in a SOIC-8 or PDIP-7 package. It features high drive capability, making it suitable for driving large gate-charge MOSFETs. The NCP1216D65R2G incorporates internal ramp compensation and built-in frequency jittering, which enhance the design of modern AC-DC adapters by improving EMI signature and preventing sub-harmonic oscillations. The controller also includes a dynamic self-supply (DSS) mechanism, eliminating the need for an auxiliary winding and providing a fully independent VCC level from the high-voltage rail.
Key Specifications
| Characteristic | Min | Typ | Max | Unit |
|---|---|---|---|---|
| Oscillation Frequency (65 kHz Version) | 58.5 | 65 | 71.5 | kHz |
| Oscillation Frequency (100 kHz Version) | 90 | 100 | 110 | kHz |
| Oscillation Frequency (133 kHz Version) | 120 | 133 | 146 | kHz |
| Maximum Duty Cycle (NCP1216) | 69 | - | 75 | % |
| Maximum Duty Cycle (NCP1216A) | 42 | - | 50 | % |
| Peak Current Capability | - | - | 500 mA | - |
| High-Voltage Current Source | 8.0 | 9.0 | - | mA |
| Output Voltage Rise-time @ CL = 1.0 nF | - | 60 | - | ns |
| Output Voltage Fall-time @ CL = 1.0 nF | - | 20 | - | ns |
| Source Resistance | 15 | - | 35 | Ω |
| Sink Resistance | 5.0 | - | 18 | Ω |
| Maximum Junction Temperature | - | - | 150 | °C |
| Temperature Shutdown | - | - | 155 | °C |
Key Features
- No Auxiliary Winding Operation: The NCP1216D65R2G uses Dynamic Self-Supply (DSS) to generate VCC from the high-voltage rail, eliminating the need for an auxiliary winding.
- Current-Mode Control with Adjustable Skip-Cycle Capability: Allows for efficient operation at light loads by adjusting the skip cycle level.
- Internal Ramp Compensation: Prevents sub-harmonic oscillations in continuous conduction mode designs.
- Built-In Frequency Jittering: Improves EMI signature by modulating the internal switching frequency.
- Auto-Recovery Internal Output Short-Circuit Protection: Protects the device from overcurrent conditions and automatically recovers once the fault is cleared.
- Extremely Low No-Load Standby Power: Reduces power consumption during standby or light load conditions.
- High Drive Capability: Drives large gate-charge MOSFETs efficiently.
- Internal 1.0 ms Soft-Start (NCP1216A Only): Ensures smooth startup of the power supply.
- Limited Duty Cycle to 50% (NCP1216A Only): Limits the maximum duty cycle to prevent overloading.
Applications
The NCP1216D65R2G is ideal for various high-power applications, including:
- AC-DC Adapters: particularly in low-cost designs where a low part count is crucial.
- TV Power Supplies: due to its high-performance and efficient operation.
- Battery Chargers: benefits from the dynamic self-supply and adjustable skip cycle features.
- Universal Off-Line Supplies: suitable for a wide range of input voltages and output requirements.
Q & A
- What is the primary function of the NCP1216D65R2G?
The NCP1216D65R2G is a PWM Current-Mode Controller designed for high-power universal off-line supplies.
- What is the Dynamic Self-Supply (DSS) feature?
The DSS feature allows the controller to generate VCC from the high-voltage rail, eliminating the need for an auxiliary winding.
- How does the NCP1216D65R2G handle overcurrent conditions?
The device enters a safe burst mode during overcurrent conditions and automatically recovers once the fault is cleared.
- What are the available switching frequencies for the NCP1216D65R2G?
The available switching frequencies are 65 kHz, 100 kHz, and 133 kHz.
- How does the internal ramp compensation work?
Internal ramp compensation prevents sub-harmonic oscillations in continuous conduction mode designs by injecting a given amount of ramp compensation via a resistor connected to the Current Sense (CS) pin.
- What is the purpose of the adjustable skip cycle feature?
The adjustable skip cycle feature allows for efficient operation at light loads by adjusting the level at which the skip cycle takes place, ensuring noise-free operation.
- How does the built-in frequency jittering improve EMI signature?
The built-in frequency jittering modulates the internal switching frequency, which softens the controller’s EMI signature.
- What is the maximum duty cycle for the NCP1216 and NCP1216A versions?
The maximum duty cycle for the NCP1216 is 75%, and for the NCP1216A, it is limited to 50%.
- What are the typical applications of the NCP1216D65R2G?
Typical applications include AC-DC adapters, TV power supplies, battery chargers, and universal off-line supplies.
- How does the NCP1216D65R2G handle standby power consumption?
The device features extremely low no-load standby power, reducing power consumption during standby or light load conditions.
