Send an Inquiry

To receive a quote for your project, please fill in the following information, and we’ll get back to you promptly.

Submit Inventory List

Please fill in the following information, and we’ll get back to you promptly.

Home > Products > Integrated Circuits (ICs) > Power Management (PMIC) > Lighting, Ballast Controllers

STMicroelectronics L6574D

Name: L6574D
Brand: STMicroelectronics
SKU: L6574D
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

Compare

Part No.:: L6574D

Manufacturer:: STMicroelectronics

Category:: Lighting, Ballast Controllers

Package:: 16-SOIC (0.154", 3.90mm Width)

Datasheet:: L6574D.pdf

Description:: IC CFL/TL CNTRL 120KHZ 16SO

Quantity:: RFQ Add To RFQ list

Payment:

Shipping:

Inventory:1,480

Please send an inquiry. Send us your inquiry, and we will respond immediately.

Product details

Overview

L6574D from STMicroelectronics is a high-voltage CFL/TL ballast controller IC designed for half-bridge fluorescent lamp driving, featuring integrated bootstrap diode, 600V rail capability, ±50 V/ns dV/dt immunity, 250mA source / 450mA sink driver current, and 80/40ns rise/fall times with 1nF load. It enables preheat, ignition, and closed-loop lamp current control in electronic ballasts.

For engineers reviewing the L6574D datasheet, L6574D pinout, L6574D application, or L6574D equivalent, key selection considerations include its dedicated preheat timing (CPRE), frequency-shifting oscillator (RPRE/CF/RING), integrated op-amp for current feedback, dual enable inputs (EN1/EN2) for fault recovery, and SO16/DIP16 package compatibility with high-side floating drive requirements.

Technical Context

The L6574D implements a current-controlled voltage oscillator with independently set preheat (fPRE = 120 kHz typ.) and ignition (fING = 60 kHz typ.) frequencies, controlled via external RPRE, RING, and CF components. Its timing section generates precise tPRE (preheat) and tSH (frequency shift) intervals using dual-current charging of CPRE.

The integrated op-amp (GBW = 1 MHz, VIO = ±10 mV) provides closed-loop lamp current regulation by feeding back to the RING pin through an external resistor-diode network. The patented bootstrap section replaces discrete diodes using a synchronous HV DMOS switch between VBOOT and VS, with internal clamping on VS (15.6 V typ.) and 5 µA leakage at 580 V.

Key Specifications

Parameter	Value and Actual Design Meaning
Max rail voltage	600 V - supports direct connection to rectified mains without external voltage reduction
dV/dt immunity	±50 V/ns - ensures robust operation under fast transient noise in lamp ballast EMI environments
Driver output current	250 mA source / 450 mA sink - drives standard MOSFET gates (e.g., size 4) with minimal external buffering
Switching time (1nF)	80 ns rise / 40 ns fall - enables high-frequency operation up to 126 kHz while minimizing switching losses
Oscillator accuracy	fPRE = 120 kHz ±5%, fING = 60 kHz ±3% - guarantees reliable lamp preheat and ignition across temperature (-40°C to +125°C)
Preheat timing constant	KPRE = 1.5 s/µF - sets tPRE = KPRE × CPRE (e.g., 495 ms with 330 nF), independent of supply and temperature
Op-amp GBW	1 MHz - supports stable closed-loop current regulation bandwidth up to ~100 kHz for flicker-free lamp operation

Pinout & Package

Available in SO16 narrow (3.94 mm × 9.9 mm) and DIP16 (7.87 mm × 20.0 mm) packages, both rated for 80 °C/W (SO16N) and 120 °C/W (DIP16) junction-to-ambient thermal resistance.

Pin/Terminal	Circuit Role	Design Meaning
1 CPRE	Preheat timing capacitor node	Charged with fixed current to 3.5 V for tPRE; recharged at reduced rate for tSH = 0.1 × tPRE
2 RPRE	Preheat frequency offset resistor	Sets Δf = fPRE − fIGN; pulled to 2 V reference during steady state
3 CF	Oscillator timing capacitor	Forms RC network with RPRE/RING to define fPRE and fIGN; exhibits triangular waveform in operation
4 RIGN	Ignition frequency resistor	Sets fIGN baseline; held at 2 V reference during normal operation
5 OPout	Op-amp output	Drives RING via external network to modulate oscillator frequency for closed-loop current control
6 OPin− / 7 OPin+	Differential sense inputs	Accept lamp current sense signal (e.g., from shunt); common-mode range −0.2 V to 3 V
8 EN1	Fault latched shutdown input	Active-high; forces immediate stop (LVG/HVG low, oscillator halted) on lamp removal or overvoltage
9 EN2	Restart trigger input	Active-high; initiates full preheat–ignition sequence, useful after failed first attempt
10 GND	Analog/digital ground reference	Common return for low-side circuitry and op-amp; isolated from high-side floating domain
11 LVG	Low-side gate driver output	Drives source-connected MOSFET gate; 250 mA source / 450 mA sink capability
12 VS	Low-side supply input	Internally clamped at 15.6 V; supplies logic and low-side driver; must be decoupled near IC
13 N.C.	No-connect isolation barrier	Physically separates LV and HV pins to prevent creepage/crosstalk in high-voltage ballast PCB layout
14 OUT	High-side floating reference	Connected to source of high-side MOSFET; defines local ground for HVG and VBOOT domains
15 HVG	High-side gate driver output	Drives high-side MOSFET gate referenced to OUT; synchronized with LVG for dead-time control
16 VBOOT	Bootstrap supply input	Receives charge via integrated HV DMOS switch; eliminates external bootstrap diode; rated to 618 V

Key Features

Feature	Design Value
Integrated bootstrap diode	Patented HV DMOS replaces discrete diode, reducing BOM count and improving reliability in cost-sensitive ballasts
Dual enable inputs (EN1/EN2)	EN1 provides latch-off protection for hard faults (e.g., lamp removal); EN2 enables safe retry without power cycle
Programmable preheat & frequency shift	CPRE-based timing ensures consistent filament heating before ignition, preventing cathode sputtering and extending lamp life
Current-controlled oscillator	Direct lamp current feedback via op-amp adjusts frequency to maintain constant power during burn, improving efficacy and stability
High dV/dt immunity	±50 V/ns tolerance across full temperature range eliminates false triggering from EMI in compact ballast enclosures

Applications

Compact Fluorescent Lamp (CFL) Ballast

Tubular Fluorescent (TL) Ballast

Use Scenario: Integrated electronic ballast in 5–25 W self-ballasted CFL retrofit lamps.

IC Role / Device Role / Timing Role: Half-bridge controller managing preheat (tPRE), ignition (tSH), and steady-state current regulation via op-amp feedback.

Use Value: Enables single-chip, low-component-count design meeting IEC 61000-3-2 harmonic limits and >10,000-hour lamp life.

Use Scenario: Slim-profile TL ballast for office lighting fixtures (e.g., T5 14–54 W).

IC Role / Device Role / Timing Role: High-voltage timing and gate driver for resonant half-bridge, coordinating frequency sweep from fPRE to fIGN.

Use Value: Delivers soft-start, zero-voltage switching (ZVS)-assisted ignition, and dimming compatibility via RPRE modulation.

Dimmable Fluorescent Lighting

Lamp Protection System

Use Scenario: Phase-cut or 0–10 V dimmable fluorescent fixture with analog brightness control.

IC Role / Device Role / Timing Role: Oscillator frequency modulator where RPRE or RING is varied to adjust lamp power while maintaining stable arc.

Use Value: Achieves smooth 10–100% dimming without audible noise or lamp flicker, using only passive component tuning.

Use Scenario: Fail-safe ballast detecting open-circuit, short-circuit, or end-of-life lamp conditions.

IC Role / Device Role / Timing Role: Fault monitor using EN1 comparator (0.6 V threshold) and op-amp saturation detection on OPout.

Use Value: Prevents catastrophic failure by latching off on lamp removal and enabling automatic restart via EN2 after cooling.

Equivalent & Alternatives

The following parts are listed as comparable options for similar fluorescent lamp ballast controller applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
IRS2166D	Integrated 600V half-bridge driver + oscillator; no dedicated op-amp; uses VCC-based preheat timing	Lacks closed-loop current regulation; relies on open-loop frequency sweep for ignition	Select when BOM minimization is critical and lamp current stability is secondary to cost
UCC3305	BiCMOS process; higher op-amp GBW (2.5 MHz); separate preheat/ignition comparators; no integrated bootstrap	Requires external bootstrap diode and Zener clamp; offers finer frequency resolution via voltage-controlled oscillator	Select for high-precision dimming or wide ambient temperature range (−55°C to +125°C)

Compared with IRS2166D and UCC3305, the L6574D uniquely combines integrated bootstrap, dedicated op-amp feedback, and dual-enable fault handling in a single SO16/DIP16 package-making it optimal for cost-sensitive, high-reliability CFL/TL ballasts requiring lamp life extension and EMI robustness.

Availability

L6574D is available at Aetrix Electronics and suitable for compact fluorescent lamp (CFL) ballasts, tubular fluorescent (TL) lighting systems, and dimmable fluorescent fixtures requiring stable component supply, long-lifecycle support, and RoHS-compliant packaging.

Supply support for L6574D 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing analog, microcontroller, power, and sensor solutions for industrial, automotive, and consumer markets.

The L6574D belongs to ST's legacy AC-DC and lighting control product line, engineered specifically for high-efficiency, low-BOM electronic ballasts targeting energy-efficient fluorescent lighting replacement in residential and commercial applications.

FAQ

What is the purpose of the CPRE pin and how does it affect lamp life?

The CPRE pin connects to a capacitor that sets preheat time (tPRE = 1.5 s/µF × CPRE) and frequency-shift duration (tSH = 0.1 × tPRE). Accurate preheating prevents cold-cathode sputtering during ignition, directly extending fluorescent lamp life beyond 10,000 hours. At end-of-life, CPRE voltage stabilizes at 5 V in steady state.

Can the L6574D drive IGBTs instead of MOSFETs in the half-bridge?

Yes-the L6574D's 450 mA sink / 250 mA source gate drive strength and 600 V rail rating support standard 600 V IGBTs. However, due to slower IGBT switching, rise/fall times exceed 80/40 ns with 1 nF load; external gate resistors may be needed to limit peak current and ensure safe SOA operation.

How does the integrated bootstrap section eliminate the external diode?

A patented high-voltage DMOS transistor, driven synchronously with the low-side gate (LVG), charges the bootstrap capacitor during LVG low phase. This replaces the conventional discrete bootstrap diode, reducing component count, forward voltage drop, and thermal stress-while maintaining VBOOT regulation up to 618 V.

What protection features does the L6574D provide against lamp failure?

The L6574D includes EN1 latched shutdown (triggered by overvoltage or lamp removal), UVLO (9.5–8.7 V hysteresis), VS clamping (15.6 V), and op-amp saturation detection. EN2 allows safe restart without power cycling. These features prevent MOSFET destruction and electrolytic capacitor overstress during open- or short-circuit lamp conditions.

L6574D Specifications

Product attributes: Attribute value

Manufacturer:: STMicroelectronics

Series:: -

Package/Case:: 16-SOIC (0.154", 3.90mm Width)

Packaging:: Tube

Product Status:: Active

Type:: CFL/TL Controller

Frequency:: 60kHz ~ 120kHz

Voltage - Supply:: 10V ~ 15.6V

Current - Supply:: 2 mA

Current - Output Source/Sink:: -

Dimming:: Yes

Operating Temperature:: -40°C ~ 125°C

Grade:: -

Qualification:: -

Mounting Type:: Surface Mount

Supplier Device Package:: 16-SO

L6574D FAQ

1.How can I place an order for L6574D through Aetrix?

Please submit a Request for Quotation (RFQ) for L6574D on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.

2.Are the price and stock information for L6574D reliable?

The price and inventory of L6574D are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for L6574D is usually 5 days.

3.What payment methods are accepted for L6574D?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for L6574D transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for L6574D?

L6574D orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your L6574D order is processed, you will receive an email with the shipment details and tracking number.

Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.

5.How can I obtain technical support or documentation for L6574D?

For technical support, including L6574D datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your L6574D requirements.

6.How does Aetrix verify that L6574D is sourced from the original manufacturer or authorized distributors?

All L6574D products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that L6574D meets industry standards.

7.What is the process for return or replacement of L6574D?

All L6574D units undergo pre-shipment inspection (PSI). If there is an issue with L6574D, returns or replacements are accepted under the following conditions:

1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.

2.The issue is reported within 90 days of delivery.

3.The L6574D part is unused and in its original packaging.

Return procedure for L6574D:

1.Submit a request within 90 days.

2.Obtain a Return Material Authorization (RMA) from Aetrix.

Tech Hub

2026-09-08 Obsolete Electronic Components: How to Source and Evaluate Replacements

A practical engineering and sourcing framework covering lifecycle verification, lifetime-buy calculations, replacement qualification, supplier checks and counterfeit-risk controls.

2026-09-07 TTL vs CMOS Logic Levels: 74HC and 74HCT Compatibility Explained

TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.

2026-09-04 Logic Level Shifter: How to Connect 3.3V and 5V Logic Safely

A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.

2026-09-03 74HC595 vs TPIC6B595: Output Drive, Pinout, Current, and Load Selection

The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…

2026-09-02 74HC595 Pinout, Timing, Output Current, and Applications

The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…

2026-09-01 Latch vs Flip-Flop: Timing, Differences and Design Choices

A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…

2026-08-30 D Latch Circuit: Truth Table, Timing, ICs and Applications

A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …

2026-08-28 SR Latch Explained: NOR and NAND Circuits, Truth Tables, and Applications

An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…

2026-08-27 Latch Circuit: SR and D Latches, Truth Tables, Timing, and Applications

Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…

2026-08-21 What Is an LED Driver? Types, Circuits, Dimming, and Selection

An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…