Features and Benefits
- Wide Input Voltage Range: 5V to 38V
- Supports Boost or SEPIC Power Topologies
- Adjustable LED Current Up to 1.6A
- 40V 10A Internal Power Switch
- Wide Temperature Range: −40°C to 150°C
- Input and Output Current Reporting
- Internal Switch for PWM and Output Disconnect
- Internal Spread Spectrum Frequency Modulation
- 3000:1 True Color PWM™ Dimming
- Open LED Protection with OPENLED Flag
- Short-Circuit Protection and SHORTLED Flag
- Soft-Start with Programmable Fault Restart Timer
- 9mm × 11.25mm × 2.22mm BGA
The LTM8005 is a 38VIN, 38VOUT boost μModule (power micromodule) LED driver designed to regulate current or voltage and is ideal for driving LEDs. The fixed frequency and current mode architecture result in stable operation over a wide range of supply and output voltages. Spread spectrum frequency modulation (SSFM) can be activated for improved electromagnetic compatibility (EMC) performance. The ground-referred voltage FB pin serves as the input for several LED protection features, and also allows the converter to operate as a constant voltage source. The PWM input provides LED dimming ratios of up to 3000:1, and the CTRL inputs provide additional analog dimming capability.
The low profile package enables utilization of unused space on the bottom of PC boards. The LTM8005 is packaged in thermally enhanced, compact over-molded Ball Grid Array (BGA) package suitable for automated assembly by standard surface mount equipment. The LTM8005 is RoHS compliant.
- High Power LED, High Voltage LED
- Accurate Current-Limited Voltage Regulators
Product Lifecycle Production
At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.
Evaluation Kits (1)
Demonstration circuit 2257A features the LTM8005 – a 38VIN, 38VOUT boost μModule® LED driver that can disconnect the output to protect against faults and provides spread spectrum switching to simplify emissions compliance. DC2257A is an LED driver with an input range for normal operation from 6V to 27V. OVLO becomes active for inputs above 29V and the maximum input voltage is 38V. The LED current is 1.2A and the base switching frequency is 350kHz. The efficiency is 92% when the input is 12V with a 35V LED load. 35V is the maximum LED voltage.
The demo circuit requires application of an external voltage to the PWM terminal for operation. The external voltage can be a DC level or an appropriate PWM dimming signal. Common frequencies for PWM dimming are 100Hz or higher. Analog dimming is achieved using the CTRL inputs.
DC2257A allows adjustments to output voltage, output current, input current, switching frequency, frequency modulation rate including disable, feedback loop compensation, EN/UVLO threshold, OVLO threshold, soft-start period, and fault latch-off or hiccup. In most cases, adjustment is made by modifying the appropriate resistor or capacitor component(s).
DC2257A provides outputs for input and output current monitoring and fault status for short and open LEDs.
The demo circuit is designed to be easily reconfigured to buck mode, buck-boost mode and SEPIC topologies. There are placeholders to mount optional LC input filter components.
The LTM8005 data sheet must be read in conjunction with this demo manual to properly use or modify DC2257A.
Tools & Simulations
LTspice® is a powerful, fast and free simulation software, schematic capture and waveform viewer with enhancements and models for improving the simulation of analog circuits.
Models for the following parts are available in LTspice:
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal.
Sample & Buy
The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.