The NCP1236 is a new fixed−frequency current−mode controller featuring Dynamic Self−Supply (DSS). This device is pin−to−pin compatible with the previous NCP12xx families.
●The DSS function greatly simplifies the design of the auxiliary supply and the VCC capacitor by activating the internal startup current source to supply the controller during transients.
●Finally, due to a careful design, the precision of critical parameters is well controlled over the entire temperature range (−40C to +125C).
●Features
● Fixed−Frequency Current−Mode Operation with Built−In Ramp Compensation
● 65 kHz or 100 kHz Oscillator Frequency
● Frequency Foldback then Skip Mode for Maximized Performance in Light Load and Standby Conditions
● Timer−Based Overload Protection with Latched (option A) or Auto−Recovery (option B) Operation, Shortened Overload Timer for Increased Safety (options C and D)
● High−voltage Current Source with Brown−Out
●detection and Dynamic Self−Supply, Simplifying the Design of the VCC Capacitor
● Frequency Modulation for Softened EMI Signature, including during Frequency Foldback mode
● Adjustable Overpower Compensation
● Latch−off Input for Severe Fault Conditions, Allowing Direct Connection of an NTC for Overtemperature Protection (OTP)
● VCC Operation up to 28 V, with Overvoltage Detection
● 500 mA Peak Source / Sink Current Drive Capability
● 4.0 ms Soft−Start
