NCP1200A is a PWM current-mode controller that can achieve low standby power for universal offline power supplies. It is housed in SOIC-8 or PDIP-8 package, and can reduce optocoupler current while increasing drive capability. Due to its novel concept, the circuit can implement complete offline AC-DC adapters, battery charger or a SMPS where standby power is a key parameter. The controller operates at a fixed 40 kHz, 60 kHz or 100 kHz, and supplies itself from the high-voltage rail, avoiding the need for an auxiliary winding. This feature naturally eases the designer's task in battery charger applications. Finally, current-mode control provides an excellent audio-susceptibility and inherent pulse-by-pulse control. When the current setpoint falls below a given value, e.g. the output power demand diminishes, the IC automatically enters the so-called skip cycle mode and provides excellent efficiency at light loads. Because this occurs at a user adjustable low peak current, no acoustic noise takes place. The NCP1200A features an efficient protective circuitry which, in presence of an overcurrent condition, disables the output pulses while the device enters a safe burst mode, trying to restart. Once the default has gone, the device auto-recovers.
The NCP1200A is a PWM current-mode controller designed for universal off-line supplies, battery chargers, and auxiliary power supplies. It features an internal structure operating at fixed frequencies of 40 kHz, 60 kHz, or 100 kHz, which allows the device to supply itself from the high-voltage rail without requiring an auxiliary winding. This design simplifies circuit implementation for battery charger applications and ensures excellent audio susceptibility through inherent pulse-by-pulse control.
| Operating Frequency | 40 kHz, 60 kHz, 100 kHz |
|---|---|
| Peak Current Capability | 250 mA |
| Maximum Junction Temperature | 150 °C |
| Temperature Shutdown | 145 °C |
| Storage Temperature Range | -60 to +150 °C |
| Power Supply Voltage (Vcc) | 16 V |
| Oscillation Frequency (40 kHz Version) | 37 to 48 kHz |
| Oscillation Frequency (60 kHz Version) | 53 to 68 kHz |
| Oscillation Frequency (100 kHz Version) | 90 to 114 kHz |
| Maximum Duty Cycle | 87 % |
The controller operates at fixed frequencies of 40 kHz, 60 kHz, or 100 kHz.
No, the controller supplies itself from the high-voltage rail, avoiding the need for an auxiliary winding.
The device has a peak current capability of 250 mA.