LED AC/DC Driver Board has Built-in Protection

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[ NCP1014 | NCP1027 | Featured Products | Datasheets | Application Notes | Buy Now ]

ON Semiconductor is offering a high performance PCB solution for powering strings of LEDs.

The NCP1014/NCP1027 LED driver board provides a constant current, constant voltage output with a maximum header voltage. It is based on a discontinuous flyback converter topology operating at 100kHz. Different configurations of the board are available, employing either the NCP1014 or NCP1027 AC/DC controller, depending on the power requirements.

Using the NCP1014, the board provides up to 24V and 350mA. With the NCP1027, on the other hand, up to 18V is available, with a maximum current of 700mA. Alternatively, a board based on the NCP1027 can be used to provide a 12V/1A power rail. The NCP1027 version also provides a higher power rating of up to 13W in addition to a line brownout function.

Line brownout prevents lethal runaway in low input voltage conditions, blocking the activity of the device until a sufficiently high input level is reached. The NCP1027 includes a portion of adjustable circuitry to support this feature.

There are a number of protection functions present on both the NCP1014 and NCP1027 parts. For example, these devices include auto recovery, internal and shortcircuit protection.

This facility constantly monitors the V_CC level and temporarily halts the activity of the device in the event of an unexpected feedback loop runaway.

 

 

Features 90V to 265V AC input voltage range Continuous output power: <8W (NCP1014) <15W (NCP1027) Output open circuit voltage clamping Frequency jittering for reduced EMI Built-in thermal shutdown protection

Applications Signage and channel lighting Architectural lighting Display lighting

 

 

NCP1014: Self-Supply Monolithic Switcher for Low Standby-Power Offline SMPS
The NCP101X series integrates a fixed-frequency current mode controller and a 700V voltage MOSFET. Housed in a PDIP7 package, the NCP101X offers everything needed to build a rugged and low-cost power supply, including soft-start, frequency jittering, short-circuit protection, skip cycle, a maximum peak current set point and a Dynamic Self-Supply (no need for an auxiliary winding).

Unlike other monolithic solutions, the NCP101X is quiet by nature: during nominal load operation, the part switches at one of the available frequencies (65-100-130kHz). When the current set point 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 typically 1/4 of the maximum peak value, no acoustic noise takes place. As a result, standby power is reduced to the minimum without acoustic noise generation.

 

Features Built-in 700V MOSFET with Typical RDS (on) 11OΩ Large creepage distance between high voltage pins Skip Cycle operation at low peak currents only: No Acoustic Noise! Dynamic self supply, no need for an Auxiliary winding Internal 1.0ms soft start Auto-recovery, internal output short-circuit protection Latched over voltage protection with auxiliary winding operation Below 100mW standby power if auxiliary winding is used Direct opto-coupler connection SPICE models available for transient and AC analysis Current- mode fixed frequency operation: 65kHz-100kHz

Applications Low power AC/DC adapters for charges Auxiliary power supplies (USB, appliances, TVs, etc.)

 

 

NCP1027: High Voltage Switcher for Medium Power Offline SMPS
The NCP1027 offers a new solution targeting output power levels from a few watts up to 15W in a universal mains fly back application. Our proprietary high-voltage technology lets us include a power MOSFET together with a startup current source, all directly connected to the bulk capacitor. To prevent lethal runaway in low input voltage conditions, an adjustable brown-out circuitry blocks the activity until sufficient input level is reached.

Current mode operation together with adjustable ramp compensation offers superior performance in universal mains applications. Protection wise, a timer detects an overload or a short-circuit and stops all operations, ensuring a safe auto-recovery, low duty cycle burst operation. An integrated, auto-recovery, Over voltage protection permanently monitors the V_CC level and temporarily shuts down the driving pulses in case of an unexpected feedback loop runaway.

Finally, a great R_DS (on) figure makes the circuit an excellent choice for standby/auxiliary offline power supplies or applications requiring higher output power levels.

 

Features Built-in 700V MOSFET with Typical RDS (on) of 5.8 , Tj = 25°C Current-mode fixed frequency operation: 65 and 100kHz Fixed peak current of 800mA Proprietary Soft Skip-Cycle operation at low peak currents Internal current source for clean and lossless startup sequence Auto-recovery output short circuit protection with timer-based detection Auto-recovery over voltage protection with auxiliary winding operation Programmable brown-out input for low input voltage detection Input to permanently latchoff the part No-load input standby power of 85mW @ 265V AC 500mW loaded, input power of 715mW @ 230V AC Programmable over power protection

Applications Medium power AC-DC adapters for chargers Auxiliary power supply

 

 

NCP1014 Offline LED Driver Evaluation Board

 

 

NCP1027 5.0V/2.0A Standby ATX Power Supply Evaluation Board

 

 Application Notes for NCP1014AP065G and NCP1014ST100T3G

Title	Download
3 Output, 10 W Off-line Power Supply
5 W, CCCV Cell Phone Battery Charger
8 W Off-Line Non-Isolated Buck Regulator
8 W, 3-Output Off-Line Switcher

 

 

 Featured Products

Part Number		Description	Data Sheet	App. Notes
NCP1014AP065G		Self-Supply Monolithic Switcher for Low Standby-Power Offline SMPS
NCP1014LEDEVB		NCP1014 Offline LED Driver Evaluation Board			Order Now
NCP1014ST100T3G		Self-Supply Monolithic Switcher for Low Standby-Power Offline SMPS
NCP1027ATXEVB		NCP1027 5.0 V/2.0 A Standby ATX Power Supply Evaluation Board			Order Now
NCP1027P065G		High Voltage Switcher for Medium Power Offline SMPS

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