NXP Semiconductors SSL1623PH/N1,112

Overview

SSL1623PH/N1,112 from NXP Semiconductors is a high-voltage SMPS controller IC for primary-side-controlled flyback LED drivers, integrating a 650 V/6.5 Ω power MOSFET and valley-switching logic. It operates directly from universal AC mains (80–276 V), delivers up to 25 W output power, and supports both constant-voltage and constant-current LED operation with primary or optocoupler feedback.

For engineers reviewing the SSL1623PH/N1,112 datasheet, SSL1623PH/N1,112 pinout, SSL1623PH/N1,112 application, or SSL1623PH/N1,112 equivalent, key selection criteria include its integrated 650 V switch, valley-switching efficiency optimization, adjustable oscillator frequency (10–200 kHz), undervoltage/overtemperature/short-winding protection, and DIP16 package compatibility with mains-isolated LED ballast designs.

Technical Context

The SSL1623PH/N1,112 implements voltage-mode control in a self-oscillating or fixed-frequency flyback topology, using auxiliary winding demagnetization sensing via pin AUX and regulation feedback via pin REG. Its valley-switching circuit detects drain ringing minima (200–800 kHz) to minimize capacitive turn-on losses, with timing governed by RC oscillator charge/discharge and internal 20 dB error amplifier gain.

Start-up occurs from rectified mains at VCC ≥ 9.5 V; operation transitions to auxiliary winding supply once VCC exceeds 8.5 V, with undervoltage lockout at ≤7.5 V. Protection includes cycle-by-cycle overcurrent detection (via SOURCE pin voltage threshold of 0.50 V), short-winding detection (0.75 V), thermal shutdown at 160 °C, and safe restart after fault clearance.

Key Specifications

Pinout & Package

SSL1623PH/N1,112 is housed in a plastic dual in-line package (DIP16, SOT38-1), 300 mil wide, with 16 leads and long body profile. Pin 1 index and seating plane comply with JEDEC MO-001 and IEC standards.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar SMPS controller applications.

Compared with SSL1623PH/N1,112, SSL1523PH/N1,112 offers lower system cost below 15 W but sacrifices voltage margin and power capability, while UCC28810DR provides greater scalability beyond 25 W at the expense of integration and board space.

Availability

SSL1623PH/N1,112 is available at Aetrix Electronics and suitable for LED ballasts, contour lighting, and commercial retail displays requiring stable component supply, long-lifecycle assurance, and consistent parametric performance across production batches.

Supply support for SSL1623PH/N1,112 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 SSL1623PH/N1,112 belongs to NXP's SSL (Smart Lighting Solutions) family, designed specifically for cost-sensitive, high-efficiency AC-DC LED drivers targeting residential, architectural, and commercial lighting markets.

FAQ

What is the maximum continuous output power supported by the SSL1623PH/N1,112?

The SSL1623PH/N1,112 is rated for LED applications up to 25 W output power. This limit is determined by its integrated 650 V/6.5 Ω MOSFET's thermal and conduction capabilities, validated under universal AC mains (80–276 V) and ambient temperatures ≤50 °C. Applications below 15 W are more suited to the SSL152x family, per NXP's design guidance.

How does valley switching improve efficiency in the SSL1623PH/N1,112?

Valley switching in the SSL1623PH/N1,112 reduces capacitive turn-on losses by initiating each primary stroke near the minimum drain voltage point of the transformer's secondary ringing waveform. At 480 kHz ringing frequency, it achieves exact valley switching; even at 200 kHz, it starts 33° before the valley-still delivering significant loss reduction and enabling >80 % system efficiency at full load.

Can the SSL1623PH/N1,112 operate without an optocoupler?

Yes, the SSL1623PH/N1,112 supports primary-side regulation without an optocoupler by using the auxiliary winding for demagnetization sensing and feedback via the REG pin. This configuration achieves approximately ±8 % output voltage accuracy. An optocoupler may be added for tighter regulation, with primary sensing remaining active as a safety backup if opto feedback fails.

What protection features are built into the SSL1623PH/N1,112?

The SSL1623PH/N1,112 integrates cycle-by-cycle overcurrent protection (via SOURCE pin voltage threshold of 0.50 V), short-winding protection (0.75 V threshold), undervoltage lockout (7.5 V stop level), and thermal shutdown at 160 °C with 2 °C hysteresis. All protections trigger safe restart mode upon fault clearance, ensuring system resilience in real-world LED lighting deployments.

What is the recommended oscillator capacitor value for the SSL1623PH/N1,112 RC pin?

NXP specifies that the oscillator capacitor connected to the RC pin of the SSL1623PH/N1,112 should be limited to approximately 1 nF to ensure full charging within the oscillator's charge time. Larger values risk incomplete charging, leading to unstable frequency control and potential regulation errors-particularly critical at low duty factors where timing precision is essential.