L99LD20Q6TR STMicroelectronics

L99LD20 High power LED driver for automotive applications Datasheet - production data Applications Low Beam High beam 4)1 / Daytime running light * * 36 Turn indicator Position light Features Side marker AEC-Q100 qualified Fog light General ST SPI communication v4.1 Description 5.5 to 24 V Operating battery voltage range The L99LD20 is a flexible LED driver, which is Load dump protected specifically designed for the control of two QFN40L 6x6 (wettable flanks) with independent high brightness LED strings for exposed pad automotive front lighting applications. It consists Timeout watchdog and limp home function of a high efficiency monolithic dual buck Low standby current converter. Buck section The buck converters integrate n-channel Integrated switching mosfets MOSFET which is driven by a bootstrap circuit. Lossless current sensing without need of When more than two LED channels are required external components on one module, then more devices L99LD20 can Very accurate LED current setting be combined also with L99LD21 device programming inductor s peak current and incorporating Boost Controller - from which peak-to-peak current ripple L99LD20 derivate. Adjustable peak current by SPI Adjustable current ripple by SPI Integrated PWM generation unit with 10-bit resolution and phase shift Peak current control Constant VLED x TOFF architecture Protection and diagnostic Battery under voltage Temperature warning (2 thresholds) Overtemperature shutdown LED voltage digital feedback through SPI Buck outputs short circuit and open load protection July 2018 DS11366 Rev 3 1/61 This is information on a product in full production. www.st.comContents L99LD20 Contents 1 Introduction 6 1.1 Typical application . 7 2 Buck converters . 11 2.1 General description 11 2.2 Bootstrap circuit .11 2.3 Peak and average current setting .11 2.4 Buck converters blank time . 13 2.5 Buck converters start-up . 14 2.6 Switching frequency . 14 3 Functional description 15 3.1 Operating modes . 15 3.1.1 Standby mode 15 3.1.2 Pre-standby mode . 16 3.1.3 Reset mode 16 3.1.4 Limp home . 16 3.1.5 Active mode 17 3.2 Programmable functions . 18 3.2.1 Activation of the buck output . 18 3.2.2 PWM dimming 18 3.3 Protections 19 3.3.1 Temperature warning . 19 3.3.2 Overtemperature shutdown 20 3.3.3 VS under voltage lockout 20 3.3.4 Buck T minimum operation 20 ON 3.3.5 Buck outputs short circuit to GND . 20 3.3.6 Buck T maximum operation 21 ON 3.3.7 Buck Open Load detection 21 4 SPI functional description . 22 4.1 SPI protocol . 22 4.2 SPI communication . 22 2/61 DS11366 Rev 3