ON Semiconductor

NCP121 is a High Accuracy 150 mA VLDO equipped with NMOS passtransistor and a separate bias supply voltage (VBIAS). The deviceprovides stable, very accurate output voltage with low noise suitablefor space constrained, noise sensitive applications. In order tooptimize performance for battery operated portable applications, theNCP121 features low IQ consumption. The XDFN6 1.2 mm x 1.2 mmpackage is optimized for use in space constrained applications

Housed in an SOIC-8 or DIP-7 package, the NCP1216 represents an enhanced version of NCP1200-based controllers. Due to its high drive capability, NCP1216 drives large gate-charge MOSFETs, which together with internal ramp compensation and built-in frequency jittering, ease the design of modern AC/DC adapters.With an internal structure operating at different fixed frequencies, the controller supplies itself from the high-voltage rail, avoiding the need of an auxiliary winding. This feature naturally eases the designer task in some particular applications, e.g. battery chargers or TV sets. Current-mode control also provides an excellent input audio-susceptibility and inherent pulse-by-pulse control. Internal ramp compensation easily prevents sub-harmonic 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 NCP1216 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.

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.

The NCP1218 represents a new, pin to pin compatible, generation of the successful 7-pin current mode NCP12XX product series. The controller allows for excellent standby power consumption by use of its adjustable skip mode and integrated high voltage startup FET. Internal frequency jittering, ramp compensation, timer-based fault detection and a latch input make this controller an excellent candidate for converters where ruggedness and component cost are the key constraints.The Dynamic Self Supply (DSS) drastically simplifies the transformer design in avoiding the use of an auxiliary winding to supply the NCP1218. This feature is particularly useful in applications where the output voltage varies during operation (e.g. battery chargers). Due to its high voltage technology, the IC can be directly connected to the high voltage dc rail.

The NCP1219 represents a new, pin to pin compatible, generation of the successful 7-pin current mode NCP12XX product series. The controller allows for excellent standby power consumption by use of its adjustable skip mode and integrated high voltage startup FET. Internal frequency jittering, ramp compensation, timer-based fault detection and a latch input make this controller an excellent candidate for converters where ruggedness and component cost are the key constraints.The Dynamic Self Supply (DSS) drastically simplifies the transformer design in avoiding the use of an auxiliary winding to supply the NCP1219. This feature is particularly useful in applications where the output voltage varies during operation (e.g. battery chargers). Due to its high voltage technology, the IC can be directly connected to the high voltage dc rail.

The NCP1230 represents a major leap towards achieving low standby power in medium-to-high power Switched-Mode Power Supplies such as notebook adapters, off-line battery chargers and consumer electronics equipment. Housed in a compact 8-pin package (SO-8 or PDIP-7), the NCP1230 contains all needed control functionality to build a rugged and efficient power supply. The NCP1230 is a current mode controller with internal ramp compensation. Among the unique features offered by the NCP1230 is an event management scheme that can disable the front-end PFC circuit during standby, thus reducing the no load power consumption. The NCP1230 itself goes into cycle skipping at light loads while limiting peak current (to 25% of nominal peak) so that no acoustic noise is generated. The NCP1230 has a high-voltage start-up circuit that eliminates external components and reduces power consumption. The NCP1230 also features an internal latching function that can be used for OVP protection. This latch is triggered by pulling the CS pin above 3.0 V and can only be reset by pulling VCC to ground. True overload protection, internal 2.5 ms soft start, internal leading edge blanking, internal frequency dithering for low EMI are some of the other important features offered by the NCP1230.

NCP1234 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.Due to frequency foldback, the controller exhibits excellent efficiency in light load condition while still achieving very low standby power consumption. Internal frequency jittering, ramp compensation, and a versatile latch input make this controller an excellent candidate for converters where component cost is the key constraint.It features a timer-based fault detection that ensures the detection of overload independently of an auxiliary winding, and an adjustable compensation to help keep the maximum power independent of the input voltage.

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.Due to frequency foldback, the controller exhibits excellent efficiency in light load condition while still achieving very low standby power consumption. Internal frequency jittering, ramp compensation, and a versatile latch input make this controller an excellent candidate for converters where component cost is the key constraint.In addition, the controller includes a new high voltage circuitry that combines a startup current source and a brown-out detector able to sense the input voltage either from the rectified ac line or the dc filtered bulk voltage. The high voltage sensing circuitry is used for the overpower protection purposes as well. Overpower protection, overload protection, and other protective features increase the safety and reliability of the final application.

The NCP1237 is a new generation of the NCP12xx fixed-frequency current-mode controllers featuring Dynamic Self-Supply (DSS), pin to pin compatible with the previous generation. The DSS function greatly simplifies the design of the auxiliary supply and the VCCcapacitor by activating the internal start-up current source to supply the controller during transients. Due to its proprietary Soft-Skip™ mode combined with frequency foldback, the controller exhibits excellent efficiency in light load condition while still achieving very low standby power consumption. This Soft-Skip feature also dramatically reduces the risk of acoustic noise, which enables the use of inexpensive transformers and capacitors in the clamping network. The NCP1237 features a dual-level timer-based fault detection that controls the amount of transient peak power that the controller can deliver for a limited time. Internal frequency jittering, ramp compensation, and a versatile latch input make this controller an excellent candidate for converters where ruggedness and components cost are the key constraints. In addition, the controller includes a new high voltage circuitry that combines a startup current source and a brown-out / line OVP detector able to sense the input voltage either from the rectified ac line or the dc filtered bulk voltage. Finally, due to a careful design, the precision of critical parameters is well controlled over the entire temperature range (-40°C to +125°C), enabling easier design and increased safety (e.g. ±5% for the peak current limit, ±7% for the oscillator).

The NCP1238 is a new generation of the NCP12xx fixed-frequency current-mode controllers featuring Dynamic Self-Supply (DSS), pin to pin compatible with the previous generation. The DSS function greatly simplifies the design of the auxiliary supply and the VCCcapacitor by activating the internal start-up current source to supply the controller during transients. Due to its proprietary Soft-Skip™ mode combined with frequency foldback, the controller exhibits excellent efficiency in light load condition while still achieving very low standby power consumption. This Soft-Skip feature also dramatically reduces the risk of acoustic noise, which enables the use of inexpensive transformers and capacitors in the clamping network. Internal frequency jittering, ramp compensation, and a versatile latch input make this controller an excellent candidate for converters where ruggedness and components cost are the key constraints. In addition, the controller includes a new high voltage circuitry that combines a startup current source and a brown-out / line OVP detector able to sense the input voltage either from the rectified ac line or the dc filtered bulk voltage. Finally, due to a careful design, the precision of critical parameters is well controlled over the entire temperature range (-40°C to +125°C), enabling easier design and increased safety (e.g. ±5% for the peak current limit, ±7% for the oscillator).