ST5000's LED5000 is a 850kHz fixed switching frequency monolithic step-down DC / DC converter controller with a drive current up to 3A, PWM LED brightness dimming, input voltage 5.5V-48V, ± 3% output current accuracy, mainly used for high Brightness LED driver, street lighting, signal signboard and general lighting. This article introduces the main features of LED5000, functional block diagram, several typical application circuits, and the main features and circuit diagram of 3A step-down LED driver STEVAL-ILL056V1.

The LED5000 device is an 850 kHz fixedswitching frequency monolithic step-down DC-DC converter designed to operate as a precise constant current source with an adjustable current capability up to 3 A DC. The embedded PWMdimming circuitry features LED brightness control. The regulated output current level is set byconnecting a sensing resistor to the feedback pin.

The 200 mV typical RSENSE voltage dropenhances perance in terms of efficiency. The size of the overall application is minimized thanks to the high switching frequency and its compatibility with ceramic output capacitors. The device is fully protected against overheating, overcurrent and output short-circuit. TheLED5000 is available in an HSOP8 package.


LED5000 main features:
 5.5 V to 48 V operating input voltage range
 850 kHz fixed switching frequency
 200 mV typ. Current sense voltage drop
 Buck / buck-boost / floating boost topologies
 PWM dimming
 ± 3% output current accuracy overtemperature
 200 m ohmtypical RDSON
 Peak current mode architecture
 Short-circuit protection
 Compliant with ceramic output capacitors
 Inhibit for zero current consumption
 Thermal shutdown
LED5000 application:
 High brightness LED driving
 Street lighting
 Signage
 Halogen bulb replacement
 General lighting

Figure 1. LED5000 functional block diagram

Figure 2. LED5000 typical application circuit diagram

Figure 3. LED5000 evaluation board application circuit diagram

3A Buck LED Driver STEVAL-ILL056V1

The STEVAL-ILL056V1 is a product evaluation board based on the LED5000, an 850 kHz fixed switching frequency monolithic step-down DC-DC converter designed to operate as a precise constant current source with an adjustable current capability up to 3 A DC. The embedded PWM dimming circuitry features LED brightness control. The regulated output current level is set by connecting a sensing resistor to the feedback pin. The 200 mV typical RSENSE voltage drop enhances perance in terms of efficiency. The size of the overall application is minimized thanks to the high switching frequency and its compatibility with ceramic output capacitors. The device is fully protected against overheating, overcurrent and output short-circuit.

3A Step-down LED Driver STEVAL-ILL056V1 Key Features:

5.5 V to 48 V operating input voltage range
850 kHz fixed switching frequency
200 mV typ. Current sense voltage drop
Buck / buck-boost / floating boost topologies
PWM dimming
± 3% output current accuracy over temperature
200 mOhm typical RDS (on)
Peak current mode architecture
Short-circuit protection
Compliant with ceramic output capacitors
Inhibit for zero current consumption
Thermal shutdown
RoHS compliant

Figure 6.3A Step-down LED driver STEVAL-ILL056V1 outline drawing

Figure 7.3A Step-down LED driver STEVAL-ILL056V1 circuit diagram

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