IS32LT3124F-ZLA3-TR ISSI

IS32LT3124A/B/C/D/E/F QUAD CHANNEL, LINEAR LED DRIVER WITH FAULT REPORTING AND DYNAMIC HEADROOM CONTROL (DHC) January 2019 GENERAL DESCRIPTION FEATURES The IS32LT3124 is a linear programmable current 5.0V to 28V input supply voltage range regulator consisting of 4 output channels capable of up - Withstand 42V load dump to 150mA each. Individual external resistors set the Four output channels can source up to 150mA maximum current level for each channel. The outputs each can be combined to provide a higher current drive - Four current set resistors capability up to 600mA (Max.). - 5% output current accuracy The IS32LT3124 features Dynamic Headroom Control - Low dropout voltage of 1V (Max.) at 100mA (DHC) with an optional external PMOS FET to - Combined for higher current capability with same minimize IC thermal stress when the supply voltage current accuracy exceeds the LED string forward voltage. It includes two PWM dimming and shutdown control input modes for different output power: Shunt Regulator - 100Hz~300Hz power supply modulation (PSM) mode and Series Regulator mode. It can operate with - 100Hz~1kHz individual dimming via resistors of power supply modulation (PSM) for applications ISETx pins (IS32LT3124B/C/E/F only) requiring dimming without use of the EN pin. Optional Dynamic Headroom Control (DHC) with For added system reliability, the IS32LT3124 an external PMOS FET to minimize IC thermal integrates fault detection circuitry for open/short circuit stress and over temperature conditions. The fault pins (FLTB) - Shunt regulator mode for heavy load can all be tied together to disable the device and other - Series regulator mode for light load IS32LT3124 devices on the same parallel circuit. Additional external UVLO (Under Voltage Lockout To handle all these different fault detection and Threshold) is programmable via EN pin reporting features, the IS32LT3124 has six different (IS32LT3124A/D only) versions: A, B, C, D, E and F. All of them can support Fault protection and reporting the above features. See table 1 for the major - Externally enable/disable fault reporting difference. In IS32LT3124A/B/D/E, if any fault (IS32LT3124B/C/E/F only) condition occurs, all output currents will be disabled. In - Programmable fault reporting output delay time IS32LT3124B/C/E/F, individual ISET pin for each LED - Fault condition disables all output channel is redefined as individual PWM dimming (IS32LT3124A/B/D/E only) control, thus ISET open detection function is removed. - Parallel fault connection (one-fail-all-fail) The EN pin of IS32LT3124B/C/E/F is featured as the - LED string open/short enable signal of the internal fault reporting block. See - Single LED short (Conditional, IS32LT3124B/C/D Table 4 for complete fault listing. only) The IS32LT3124 is targeted at the automotive market - ISET pin short such as interior accent lighting and exterior tail lighting. - ISET pin open (IS32LT3124A/D only) It is offered in a thermally enhanced eTSSOP-16 - Over temperature package. AEC-Q100 Qualified APPLICATIONS Operating temperature range (-40C ~ +125C) Automotive LED driver RGBW automotive ambient lighting Tail light Turn light Daytime running light Lumissil Microsystems www.lumissil.com 1 Rev. A, 01/02/2019 IS32LT3124A/B/C/D/E/F Table 1 Major Difference Of Different Versions Outx Pin Short To Support LED String Fault Protection Action Version Dimming GND Threshold Voltage (See Table 4 For More Details) V SCD IS32LT3124A PSM dimming or Simultaneous dimming by EN pin Typ. 1.22V 1 LED(s) One channel fails all channels off IS32LT3124B PSM dimming or Individual dimming by ISET resistors Typ. 4.8V One channel fails all channels off IS32LT3124C PSM dimming or Individual dimming by ISET resistors Typ. 4.8V One channel fails all channels on > (V +V ) SCD MAX SCD HY IS32LT3124D PSM dimming or Simultaneous dimming by EN pin Typ. 4.8V One channel fails all channels off IS32LT3124E PSM dimming or Individual dimming by ISET resistors Typ. 1.22V 1 LED(s) One channel fails all channels off IS32LT3124F PSM dimming or Individual dimming by ISET resistors Typ. 1.22V 1 LED(s) One channel fails all channels on TYPICAL APPLICATION CIRCUIT V Battery D C 1 VICC R 1 4 16 0.1F VCC VICC C VCC R R EN1 HR 1 2 Q1 EN HRSET C 1 R EN2 22nF 3 ERC IS32LT3124 11 15 FLTB OUT1 14 R FLTD 10 OUT2 FLTD 13 OUT3 R ISET1 5 12 ISET1 OUT4 R 6 ISET2 ISET2 R 7 ISET3 ISET3 R ISET4 8 9 ISET4 GND Figure 1 Typical Application Circuit V Battery Connected to VCC CVCC 2 and VICC pins of C next device VICC R D 4 16 1 4 16 1 0.1F VCC VICC VCC VICC CVCC 1 R HR 1 RHR 2 R EN1 2 Q1 1 2 1 2 R EN HRSET EN HRSET EN1 1 C1 R EN2 2 22nF R 3 3 EN2 1 ERC ERC IS32LT3124 IS32LT3124 R 10 15 R 10 15 FLTD 1 FLTD 2 FLTD OUT1 FLTD OUT1 14 14 R R ISET1 1 5 OUT2 ISET1 2 5 OUT2 ISET1 13 ISET1 13 R 6 OUT3 R 6 OUT3 ISET2 1 ISET2 2 ISET2 ISET2 RISET3 1 7 RISET3 2 7 ISET3 ISET3 8 8 ISET4 9 ISET4 9 GND GND 11 12 11 12 FLTB OUT4 FLTB OUT4 Connected to HRSET pin of next device Connected to FLTB pin of next device Figure 2 Typical Application Circuit (Several Devices in Parallel Share One External PMOS FET) Lumissil Microsystems www.lumissil.com 2 Rev. A, 01/02/2019