NCP1217A Series

PWM Controller, Fixed Frequency, Current Mode, with Duty Cycle Limited to 50%

Catalog

PWM Controller, Fixed Frequency, Current Mode, with Duty Cycle Limited to 50%

Part	Topology	Mounting Type	Voltage - Supply (Vcc/Vdd) [Min]	Voltage - Supply (Vcc/Vdd) [Max]	Fault Protection	Output Isolation	Operating Temperature [Max]	Package / Case	Package / Case	Package / Case	Frequency - Switching	Duty Cycle	Voltage - Start Up	Supplier Device Package	Package / Case [y]	Package / Case [x]
ON Semiconductor NCP1217P133G	Flyback	Through Hole	7.6 V	16 V	Over Load Over Temperature Short Circuit	Isolated	150 °C	7.62 mm	0.3 in 7 Leads	8-DIP	133 kHz	74 %	12.8 V	7-PDIP
ON Semiconductor NCP1217AD100R2G	Flyback	Surface Mount	7.6 V	16 V	Over Load Over Temperature Short Circuit	Isolated	150 °C			8-SOIC	100 kHz	46.5 %	12.8 V	8-SOIC	3.9 mm	0.154 in
ON Semiconductor NCP1217D65R2	Flyback	Surface Mount	7.6 V	16 V	Over Load Over Temperature Short Circuit	Isolated	150 °C			8-SOIC	65 kHz	74 %	12.8 V	8-SOIC	3.9 mm	0.154 in
ON Semiconductor NCP1217AP65G	Flyback	Through Hole	7.6 V	16 V	Over Load Over Temperature Short Circuit	Isolated	150 °C	7.62 mm	0.3 in 7 Leads	8-DIP	65 kHz	46.5 %	12.8 V	7-PDIP
ON Semiconductor NCP1217P133	Flyback	Through Hole	7.6 V	16 V	Over Load Over Temperature Short Circuit	Isolated	150 °C	7.62 mm	0.3 in 7 Leads	8-DIP	133 kHz	74 %	12.8 V	7-PDIP
ON Semiconductor NCP1217D133R2	Flyback	Surface Mount	7.6 V	16 V	Over Load Over Temperature Short Circuit	Isolated	150 °C			8-SOIC	133 kHz	74 %	12.8 V	8-SOIC	3.9 mm	0.154 in
ON Semiconductor NCP1217D100R2G	Flyback	Surface Mount	7.6 V	16 V	Over Load Over Temperature Short Circuit	Isolated	150 °C			8-SOIC	100 kHz	74 %	12.8 V	8-SOIC	3.9 mm	0.154 in
ON Semiconductor NCP1217P100G	Flyback	Through Hole	7.6 V	16 V	Over Load Over Temperature Short Circuit	Isolated	150 °C	7.62 mm	0.3 in 7 Leads	8-DIP	100 kHz	74 %	12.8 V	7-PDIP
ON Semiconductor NCP1217AP133	Flyback	Through Hole	7.6 V	16 V	Over Load Over Temperature Short Circuit	Isolated	150 °C	7.62 mm	0.3 in 7 Leads	8-DIP	133 kHz	46.5 %	12.8 V	7-PDIP
ON Semiconductor NCP1217P65G	Flyback	Through Hole	7.6 V	16 V	Over Load Over Temperature Short Circuit	Isolated	150 °C	7.62 mm	0.3 in 7 Leads	8-DIP	65 kHz	74 %	12.8 V	7-PDIP

Catalog

PWM Controller, Fixed Frequency, Current Mode, with Duty Cycle Limited to 50%

Key Features

• Current-Mode with adjustable skip-cycle capability

• Built-in internal ramp compensation

• Auto-recovery internal output short-circuit protection

• Full latch-off if Adjustment pin is brought high

• Extremely low no-load standby power

• Internal temperature shutdown

• 500mA peak current capability

• Fixed frequency versions at 65kHz, 100kHz and 133kHz

• Direct optocoupler connection

• Internal Leading Edge Blanking

• SPICE models available for TRANsient and AC analysis

• Internal 1ms Soft start (A version only)

• Limited Duty Cycle to 50% (A version only)

• Pb-Free Packages are Available

Description

Housed in a SOIC-7 or PDIP-7 package, the NCP1217 represents the second generation of NCP1203-based controllers. Thanks to its high drive capability, NCP1217 drives large gate-charge MOSFETs, which together with internal ramp compensation and built-in over voltage protection, ease the design of modern AC/DC adapters. NCP1217 offers a true alternative to UC384X-based designs.With an internal structure operating at different fixed frequencies (65, 100, 133kHz), the controller features a high-voltage start-up FET, which ensures a clean and loss less startup sequence. Its current-mode control topology provides an excellent input audio-susceptibility and inherent pulse-by-pulse control. Internal ramp compensation easily prevents subharmonic oscillations from taking place in continuous conduction mode designs.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 NCP1217 features two efficient protective circuitries: 1) in presence of an over-current condition, the output pulses are disabled and the device enters a safe burst mode, trying to re-start. Once the default has gone, the device auto-recovers. 2) if an external signal (e.g. a temperature sensor) pulls pin1 above 3.2V, output pulses are immediately stopped and the NCP1217 stays latched in this position. Reset occurs when the VCCcollapses to ground, e.g. the user un-plugs the power supply.