LAN1166ED 100V Low Dropout High Current Linear Constant Current IC | Qinglan Semiconductor Original | Automotive LED Driver
Keywords: LAN1166ED, 100V linear constant current IC, 4A automotive LED driver, 12V headlight chip, low dropout LED driver, thermal protection, ESOP8 package, Qinglan Semiconductor, Gsmicro authorized distributor
Description: LAN1166ED is a 100V high?voltage, 4A high?current linear constant current IC from Qinglan Semiconductor, designed specifically for 12V automotive LED strings. It features built?in 120°C thermal protection, 0.57V low dropout voltage, 100V/25A power MOSFET, and high?voltage foldback protection. Housed in an ESOP8 high?thermal?conductivity package with an ultra?simple external circuit, it is ideal for automotive headlights, tail lights, motorcycle lights, and DC high?power LED lighting – the preferred driver for high?power automotive lighting. Gsmicro Semiconductor is an authorized first?tier distributor of Qinglan Semiconductor.
Product Overview
LAN1166ED is an automotive linear constant current IC designed for 12V LED strings, supporting low dropout and high current. It requires only two external resistors to form a complete constant current drive circuit – simple BOM, low cost, and easy mass production.
Built?in 120°C thermal protection ensures stable operation under high voltage drop, keeping LED junction temperature below 130°C even in harsh high?temperature automotive environments.
Integrates a 25A/100V power MOSFET with a maximum application current of 4A. The low dropout driver achieves only 0.57V drop at 4A, resulting in low heat generation and high efficiency – ideal for 12V high?power headlights.
Built?in high?voltage protection automatically reduces output current when input voltage reaches 15V, preventing damage from voltage surges and enhancing adaptability to automotive power fluctuations.
Key Features
● 100V high withstand voltage, 4A continuous output – perfect for 12V high?power automotive headlights and work lights.
● Only 0.57V dropout at 4A – lower heat, higher efficiency, and improved fixture stability.
● Built?in 120°C thermal protection – automatic current reduction prevents overheating and LED damage.
● 15V high?voltage foldback protection – adapts to automotive power fluctuations, avoiding overvoltage failure.
● Ultra?simple external circuit – only two resistors, no capacitors, low BOM cost, easy volume production.
● ESOP8 high?thermal?conductivity package with large exposed pad – suitable for high?power, high?heat dissipation applications.
Key Electrical Parameters
| Parameter | Typical Value | Unit |
| Operating Voltage Range | 7–100 | V |
| Max Output Current | 4 | A |
| Dropout Voltage @4A | 0.57 | V |
| Thermal Protection Threshold | 120 | ℃ |
| Power MOSFET Withstand Voltage | 100 | V |
| Max Power Dissipation | 8 | W |
| Quiescent Current | 180 | uA |
Pin Description
| Pin/Area | Symbol | Description |
| 1 | VIN | Power supply input (7V–100V) |
| 2 | GND | Ground |
| 3 | CS | Current sense – external resistor sets output current |
| 4 | S | Power MOSFET source |
| 5 | DR | LED constant current output, connect to LED cathode |
| 6 | HLT/NC | No connect (float=135°C, GND=120°C OTP) |
| 7 | SGND/NC | Internal signal ground, no connect |
| 8 | SEL/NC | High?voltage protection select, GND enables OVP |
| Exposed Pad | DR | Thermal pad, connect to heatsink |
Package Outline Drawing
Typical Application Circuit
Applications
● Automotive headlights, position lights, tail lights, motorcycle lights, work lights, 12V high?power LED luminaires, DC high?power LED lighting, automotive interior lighting systems.
Application Notes
● Constant current setting: Output current Io = 0.3V ÷ Rcs. For 4A output, Rcs = 75mΩ (multiple resistors in parallel recommended).
● High?voltage protection: Connect SEL pin to GND – OVP activates at Vin ≥15V, automatically reducing current.
● Thermal management: For high power applications, use a 2?ounce thermal copper PCB with the exposed pad tightly soldered to the heatsink layer.
● Reverse polarity protection: Add a 1kΩ resistor in series with VIN to prevent damage from reverse power connection.
Drop?in Replacements
● Directly replaces SM2082, HX319A, QX7136, SL7108, OC7201C and other linear constant current ICs.
● Advantages: 100V high voltage, 4A high current, 0.57V low dropout, built?in OVP, thermal protection, simple external circuit, lower cost.
Ordering Information
| Part Number | Package | Marking | Packing |
| LAN1166ED | ESOP8 | LAN1166ED / HAYYWW | Tape & Reel, 4000/Reel |
Gsmicro Linear Automotive LED Driver Comparison
| Part Number | Package | Withstand Voltage | OTP Point | LED String | Max Current |
| LAN1032AT | SOT89-5L | 48V | 140℃ | 9V | 0.6A |
| LAN1032E | ESOP8 | 48V | 140℃ | 9V | 0.8A |
| LAN1161ED | ESOP8 | 100V | 120℃ | 12V | 1.2A |
| LAN1163E | ESOP8 | 100V | 135℃ | 12V | 1.2A |
| LAN1165ED | ESOP8 | 100V | 120℃ | 12V | 2.5A |
| LAN1165E | ESOP8 | 100V | 135℃ | 12V | 2.5A |
| LAN1166ED | ESOP8 | 100V | 120℃ | 12V | 4A |
| LAN1166E | ESOP8 | 100V | 135℃ | 12V | 4A |
| LAN1168ED | ESOP8 | 200V | 120℃ | 24V | 1.2A |
| LAN1053A | ESOP8 | 100V | 135℃ | 9V | 1.2A |
| LAN1058A | ESOP8 | 200V | 135℃ | 24V | 1.2A |
FAQ – LAN1166ED Automotive LED Driver
Q1: How to set output current with LAN1166ED?
Only two external resistors are needed. Output current Io = 0.3V ÷ Rcs. For 4A, Rcs = 75mΩ (use multiple resistors in parallel). The circuit is extremely simple and EMI?free.
Q2: Does LAN1166ED support fanless high?power automotive headlight designs?
Yes. With built?in 120°C thermal protection and only 0.57V dropout at 4A, it works stably in 12V systems when used with a 2?ounce thermal copper PCB – no fan required even for high?power applications.
Q3: What is the maximum withstand voltage and output current of LAN1166ED?
Withstand voltage: 100V; maximum continuous output current: 4A (13.5V input, 12V LED string). Designed for high?brightness 12V automotive headlights and 4?LED series configurations.
Q4: How to enable the 15V over?voltage protection feature?
Connect pin 8 (SEL) to GND. When input voltage exceeds 15V, output current automatically folds back to protect the IC and LEDs from voltage surges.
Q5: How to get samples, pricing, and technical support for LAN1166ED?
Gsmicro Semiconductor is an authorized first?tier distributor of Qinglan Semiconductor, offering free samples, reference designs, and FAE support. Contact us at +86 18018703531 (Contact: Felix Ho) or add WeChat: gsmicro_semi (mention LAN1166ED).
Distributor & Services
Gsmicro Semiconductor (Shenzhen) Co., Ltd. is an authorized first?tier distributor of Qinglan Semiconductor, specializing in the distribution and solution services of automotive LED driver ICs. We offer full series of LAN1166ED linear constant current ICs from stock, free samples, and comprehensive technical support, widely used in automotive headlights, motorcycle lights, work lights, and other high?power LED lighting applications. With stocking locations in Shenzhen and Shanghai, we provide fast delivery worldwide.
