NXP SSL21084AT

Description

The SSL21084AT is a high-voltage Integrated Circuit (IC) for driving retrofit LED lamps in general lighting applications. It enables the implementation of a very compact low-cost system solution. The IC has an integrated internal HV switch and work as Boundary Conduction Mode (BCM) buck converter.

The SSL21084AT is supplied by a start-up bleeder resistor, a dV/dt supply using capacitive coupling from the drain or any other auxiliary supply. The IC supply current is low. An internal clamp limits the supply voltage.

The IC has accurate output current control and can be operated using Pulse-Width Modulation (PWM) dimming. In addition, several protection features are available such as easy external temperature feedback.The main benefits of this IC include:

•Small Printed-Circuit Board (PCB) footprint and compact solution•High efficiency (up to 90 %) for non-dimmable high power factor solutions•High power factor (>0.9)•Ease of integration and many protection features•Low electronic Bill Of Materials (BOM)•Mains phase-cut dimmable using external components•Highly flexible IC for use in buck, buck/boost mode•Single inductor used for non-isolated configurations because of internal demagnetization detection and dV/dt supplyThe SSL21084AT is designed to start up directly from the HV supply using an internal high-voltage current source. An internal clamp limits the supply voltage.

Features

LED controller IC for driving strings of LEDs or high-voltage LED modules from a rectified mains supply

• Power-efficient boundary conduction mode operation with:
• No reverse recovery losses in freewheel diode
• Zero-Current Switching (ZCS) for switch turn-on
• Zero-voltage or valley switching for switch turn-off
• Minimal required inductance value and size
• Fast transient response through cycle-by-cycle current control:
• No overshoot or undershoot in the LED current
• Simple high input power factor solution (>0.9)
• Internal Protection features:
• UnderVoltage LockOut (UVLO)
• Leading-Edge Blanking (LEB)
• OverCurrent Protection (OCP)
• Short-winding protection (SWP); SSL21082T/SSL21084T only
• Internal OverTemperature Protection (OTP)
• Brownout protection
• Mains phase cut dimmable LED driver solution:
• Supports both leading-edge and trailing-edge dimmers
• Easy external temperature protection with a single NTC
• Open output protection using external components
• Compatible with wall switches with built-in indication light during standby
• IC lifetime easily matches or surpasses LED lamp lifetime
• Input current distributed evenly over the phase, reducing required output capacitor size and bleeder dissipation

Typical applications

• The SSL21082 and SSL21084 are intended for mains dimmable compact LED lamps for single mains input voltages. Mains input voltages include 100 V (AC), 120 V (AC) and 230 V (AC).

More information

• IC product information