LED2000 3 A monolithic step-down current source with synchronous rectification Datasheet - production data Applications High brightness LED driving Halogen bulb replacement General lighting Signage 62 1 9)4)3 Description The LED2000 is an 850 kHz fixed switching frequency monolithic step-down DC-DC converter designed to operate as precise constant current Features source with an adjustable current capability up to 3.0 V to 18 V operating input voltage range 3 A DC. The embedded PWM dimming circuitry features LED brightness control. The regulated 850 kHz fixed switching frequency output current is set connecting a sensing resistor 100 mV typ. current sense voltage drop to the feedback pin. The embedded synchronous PWM dimming rectification and the 100 mV typical R SENSE voltage drop enhance the efficiency performance. 7% output current accuracy The size of the overall application is minimized Synchronous rectification thanks to the high switching frequency and 95 m HS / 69 m LS typical R DS(on) ceramic output capacitor compatibility. The device is fully protected against thermal overheating, Peak current mode architecture overcurrent and output short-circuit. The Embedded compensation network LED2000 is available in VFQFPN 4 mm x 4 mm Internal current limiting 8-lead, and standard SO8 package. Ceramic output capacitor compliant Thermal shutdown Figure 1. Typical application circuit /( /( // 11 99 ,, B6 1 : 9 , 6 : B 1 9 , 00 ,, 0 , % ) 1 3 * ( 3 1 * 11 ,, && 77 &)/&)/ 66 55 77 88 22 && ** 11 0 Y September 2021 DocID023432 Rev 7 1/41 This is information on a product in full production. www.st.comContents LED2000 Contents 1 Pin settings 6 1.1 Pin connection 6 1.2 Pin description 6 2 Maximum ratings 7 3 Thermal data . 7 4 Electrical characteristics . 8 5 Functional description . 9 5.1 Power supply and voltage reference 10 5.2 Voltage monitor 10 5.3 Soft-start 10 5.4 Error amplifier 10 5.5 Thermal shutdown .11 6 Application notes 12 6.1 Closing the loop 12 6.2 G (s) control to output transfer function 12 CO 6.3 Error amplifier compensation network . 13 6.4 LED small signal model 15 6.5 Total loop gain . 17 6.6 Dimming operation 19 Dimming frequency vs. dimming depth . 20 6.7 EDesign Suite software 21 7 Application information . 22 7.1 Component selection 22 7.1.1 Sensing resistor . 22 7.1.2 Inductor and output capacitor selection . 22 7.1.3 Input capacitor 24 7.2 Layout considerations . 26 2/41 DocID023432 Rev 7