Overview
The LM3404HVMAX is a monolithic switching regulator designed by National Semiconductor (now part of Texas Instruments) to deliver constant currents to high power LEDs. This device is particularly suited for automotive, industrial, and general lighting applications. It features a high-side N-channel MOSFET switch with a current limit of 1.5A (typical) for step-down (Buck) regulators. The LM3404HVMAX is known for its wide input voltage range, low voltage reference, and fast output enable/disable function, making it an ideal choice for driving high power LEDs with forward currents up to 1.2A.
Key Specifications
| Parameter | Min | Typ | Max | Units |
|---|---|---|---|---|
| VIN Range | 6 | - | 75 | V |
| Output Current | - | - | 1.2 | A |
| On-time 1 | 2.1 | 2.75 | 3.4 | µs (VIN = 10V, RON = 200 kΩ) |
| On-time 2 | 515 | 675 | 835 | ns (VIN = 70V, RON = 200 kΩ) |
| RDS-ON Buck Switch On Resistance | 0.37 | 0.75 | - | Ω (ISW = 200 mA, BST-SW = 6.3 V) |
| TSD Thermal Shutdown Threshold | - | - | 165 | °C |
| TSD-HYS Thermal Shutdown Hysteresis | - | - | 25 | °C |
| Package | - | - | - | SOIC-8, SO PowerPAD™-8 |
Key Features
- Integrated 1.0A MOSFET
- Wide input voltage range: 6V to 75V
- 1.2A output current over temperature
- Cycle-by-cycle current limit
- No control loop compensation required
- LED dimming via pulse width modulation (PWM)
- Broken or open LED protection
- Low power shutdown mode
- Thermal shutdown protection
- Supports all-ceramic output capacitors and capacitor-less outputs
- Unique thermal management design to reduce device temperature rise
Applications
- LED Drivers
- Constant Current Sources
- Automotive Lighting
- General Illumination
- Industrial Lighting
Q & A
- What is the primary function of the LM3404HVMAX?
The LM3404HVMAX is designed to deliver constant currents to high power LEDs.
- What is the input voltage range for the LM3404HVMAX?
The input voltage range is from 6V to 75V.
- What is the maximum output current of the LM3404HVMAX?
The maximum output current is 1.2A over temperature.
- Does the LM3404HVMAX require control loop compensation?
No, it does not require control loop compensation due to its hysteretic mode control.
- What dimming method does the LM3404HVMAX support?
The LM3404HVMAX supports LED dimming via pulse width modulation (PWM).
- What protection features does the LM3404HVMAX have?
The device includes broken or open LED protection, low power shutdown, and thermal shutdown protection.
- What types of capacitors does the LM3404HVMAX support?
The device supports all-ceramic output capacitors and capacitor-less outputs.
- What is the thermal shutdown threshold of the LM3404HVMAX?
The thermal shutdown threshold is 165°C.
- What packages are available for the LM3404HVMAX?
The device is available in SOIC-8 and SO PowerPAD™-8 packages.
- What are some common applications for the LM3404HVMAX?
Common applications include LED drivers, constant current sources, automotive lighting, general illumination, and industrial lighting.
- How does the LM3404HVMAX manage thermal issues?
The device features a unique thermal management design to reduce the rise of the device's temperature.
