The is an LED D driver contr roller IC for driving d external MOSFETs to drive high current LEDs. is a multitopology contr roller enabling it to efficiently y control the current c through series s connected LE EDs. The multi i-topology enab bles it to operate in buck, b boost and d buck-boost co onfigurations. The 60V capa ability coupled d with its multi-topology cap pability enables be b used in a wide range of ap pplications and d drive in excess 15 5 LEDs in serie es. The is a modif fied hysteretic c controller us sing a patent pending g control sche eme providing high output current c accuracy in all a three mod des of operati ion. High acc curacy dimming is ac chieved throug gh DC control and high frequency PWM control. ns for fault diag gnosis. A flag output o The ZXLD1371 uses two pin highlights a fa ault, while the multi-level stat tus pin gives further f information on the exact fault t.

· 0.5% typic cal output curre ent accuracy to 60V operating o voltag ge range LED drive er supports Buc ck, Boost and Buck-boost B configurat tions Wide dyna amic range dim mming DC D dimming o 1000:1 dimming rang 1MH Hz switching High temp perature contro ol of LED curren nt using TADJ Available in Automotiv ve Grade wi ith AEC-Q100 0 and TS16949 certification Available in "Green" Mo olding Compou und (No Br, Sb b) with lead Free Finish/ RoHS Compliant (No ote 1)

EU Direct tive 2002/95/EC (R RoHS) 2011/65/E EU (RoHS 2). All ap pplicable RoHS exe emptions applied.

Pin Name Pin Type (Note 2) Description Adjust input (for dc output current control) Connect to REF to set 100% output current. Drive with dc voltage 1.25V) to adjust output current from 100% of set value. The ADJ pin has an internal clamp that limits the internal node to less than 3V. This provides some failsafe should they get overdriven Internal 1.25V reference voltage output Temperature Adjust input for LED thermal current control Connect thermistor/resistor network to this pin to reduce output current above a preset temperature threshold. Connect to REF to disable thermal compensation function. (See section on thermal control.) Shaping capacitor for feedback control loop Connect 330pF ±20% capacitor from this pin to ground to provide loop compensation Operation status output (analog output) Pin at 4.5V (nominal) during normal operation. Pin switches to a lower voltage to indicate specific operation warnings or fault conditions. (See section on STATUS output.) Status pin voltage is low during shutdown mode Signal ground (Connect to 0V) Power ground - Connect to 0V and pin 8 to maximize copper area Not Connected internally ­ recommend connection to pin 7, (PGND), to maximize PCB copper for thermal dissipation Not Connected internally ­ recommend connection pin 10 (GATE) to permit wide copper trace to gate of MOSFET Gate drive output to external NMOS transistor ­ connect to pin 9 Auxiliary positive supply to internal switch gate driver At VIN 8V; a bootstrap circuit is recommended to ensure adequate gate drive voltage (see Applications section) At VIN > 8V; connect to VIN At VIN >24V; to reduce power dissipation, VAUX can be connected to 15V auxiliary power supply (see Applications section). Decouple to ground with capacitor close to device (see Applications section) Input supply to device to 60V Decouple to ground with capacitor close to device (refer to Applications section) Current monitor input. Connect current sense resistor between this pin and VIN The nominal voltage, VSENSE, across the resistor is 218mV fixed in Buck mode and initially 225mV in Boost and Buck-Boost modes, varying with duty cycle. Flag open drain output Pin is high impedance during normal operation Pin switches low to indicate a fault, or warning condition Digital PWM output current control Pin driven either by open Drain or push-pull or 5V logic levels. Drive with frequency higher than 100Hz to gate output `on' and `off' during dimming control. The device enters standby mode when PWM pin is driven with logic low level for more than 15ms nominal (Refer to application section for more details) Gain setting input Used to set the device in Buck mode or Boost, Buck-boost modes and to control the sense voltage in Boost and Buck-boost modes Connect to ADJ pin for Buck mode operation For Boost and Buck-boost modes, connect to resistive divider from ADJ to SGND. The GI divider is required to compensate for duty cycle gating in the internal feedback loop (see Application section). The GI pin has an internal clamp that limits the internal node to less than 3V. This provides some failsafe should it become overdriven. Exposed paddle. Connect to 0V plane for electrical and thermal management

Symbol VIN VAUX VISM VSENSE VGATE IGATE VFLAG VPWM, VADJ, VTADJ, VGI, VPWM TJ TST Input supply voltage Auxiliary supply voltage Current monitor input relative to GND Current monitor sense voltage (VIN-VISM) Gate driver output voltage Gate driver continuous output current Flag output voltage Other input pins Maximum junction temperature Storage temperature Parameter Rating to 150 Unit V °C

Stresses greater than the 'Absolute Maximum Ratings' specified above, may cause permanent damage to the device. These are stress ratings only; functional operation of the device at these or any other conditions exceeding those indicated in this specification is not implied. Device reliability may be affected by exposure to absolute maximum rating conditions for extended periods of time. Semiconductor devices are ESD sensitive and may be damaged by exposure to ESD events. Suitable ESD precautions should be taken when handling and transporting these devices.