NXP Semiconductors SSL21083T/1,118

Overview

SSL21083T/1,118 from NXP Semiconductors is a high-voltage LED driver IC integrating a 600 V MOSFET for non-dimmable mains-powered LED lamps. It operates in boundary conduction mode (BCM) buck topology, delivers ±5 % LED current accuracy, achieves up to 95 % efficiency, and supports 100 V/120 V/230 V AC inputs. Its role is primary-side constant-current regulation in compact retrofit LED bulbs and downlights.

For engineers reviewing the SSL21083T/1,118 datasheet, SSL21083T/1,118 pinout, SSL21083T/1,118 application, or SSL21083T/1,118 equivalent, key selection criteria include integrated 600 V MOSFET capability, BCM valley-switching operation, direct PWM current regulation support, thermal shutdown with safe-restart behavior, and SO8 package compatibility with PCB thermal management via copper pour.

Technical Context

The SSL21083T/1,118 implements a peak-current-controlled BCM buck converter with internal valley detection on the DRAIN pin to enable zero-voltage switching, minimizing capacitive losses. Its control loop uses cycle-by-cycle current sensing at the SOURCE pin with leading-edge blanking (300 ns typical) and overcurrent protection threshold of 500 mV.

Startup is enabled by an internal HV current source feeding VCC, followed by dV/dt supply coupling from the DRAIN or DVDT pin; the internal VCC regulator activates only during supply dips below 9.25 V. Protection includes latched SWP/OSP and safe-restart OTP/LED overtemperature control triggered at 170 °C junction temperature.

Key Specifications

Pinout & Package

SSL21083T/1,118 is housed in an SO8 package (SOT96-1), 3.9 mm body width, with exposed pad not electrically connected. Thermal resistance R_th(j-a) is 72 K/W on JEDEC 2s2p board, enabling PCB copper to serve as primary heat sink.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar LED driver applications.

Compared with SSL21084T/1,118, the SSL21083T/1,118 eliminates dimmer interface circuitry and reduces BOM count by 3–5 components; versus MP4008GN-Z, it removes gate driver design effort and enables smaller PCB footprint but constrains max output power to ~12 W in SO8 thermal limits.

Availability

SSL21083T/1,118 is available at Aetrix Electronics and suitable for LED retrofit bulbs, downlights, tube lights, and wall-switch-compatible lamps requiring stable component supply and long-lifecycle support.

Supply support for SSL21083T/1,118 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

NXP Semiconductors is a global semiconductor company headquartered in Eindhoven, Netherlands, specializing in secure connectivity solutions for automotive, industrial, and IoT applications.

The SSL21083T/1,118 belongs to NXP's SSL (Smart Lighting Solutions) product line, designed specifically for cost-sensitive, high-efficiency, non-dimmable LED lighting systems operating directly from AC mains.

FAQ

What is the maximum output power achievable with SSL21083T/1,118 in SO8 package?

The SSL21083T/1,118 supports up to approximately 12 W of LED output power in typical SO8 PCB layouts with 2-layer 35 µm copper. This limit arises from thermal constraints: at 150 °C max junction temperature and 72 K/W thermal resistance (JEDEC 2s2p), power dissipation must stay below 0.6 W. Higher power requires enhanced copper pour or forced air cooling.

Does SSL21083T/1,118 require an external Zener diode on the VCC pin?

No, the SSL21083T/1,118 includes an internal active Zener clamp limiting VCC to 20 V maximum. As long as the dV/dt supply current minus IC consumption (1.3 mA) stays within the 20 mA IDD limit, no external Zener is needed. External clamping is only required if auxiliary supply current exceeds this margin.

How does SSL21083T/1,118 implement LED temperature protection?

The SSL21083T/1,118 uses the NTC pin to monitor LED temperature via an external NTC thermistor. When the pin voltage falls below 0.35 V, peak current is reduced linearly; below 0.29 V, a timer starts and full shutdown occurs if the low voltage persists beyond 46 µs. This provides precise, safe-restart thermal derating without external comparators.

Can SSL21083T/1,118 be used with 100 V AC, 120 V AC, and 230 V AC inputs?

Yes, the SSL21083T/1,118 is explicitly qualified for all three mains voltages. Its 600 V drain rating, wide VCC operating range (8–16 V), and brownout protection (ton(high) = 15 µs) ensure robust operation across global line voltages without hardware changes-only inductor and capacitor values require adjustment per input.

What protection features are latched versus safe-restart in SSL21083T/1,118?

In the SSL21083T/1,118, Short-Winding Protection (SWP) and Output Short Protection (OSP) are latched-requiring power cycle to reset. UnderVoltage LockOut (UVLO), OverTemperature Protection (OTP), and LED overtemperature protection are safe-restart: the IC halts, cools, then automatically resumes operation once fault conditions clear and VCC rises above 5 V.