IS32LT3128A-ZLA3-TR

IS32LT3128A TRIPLE CHANNEL LINEAR LED DRIVER WITH FADE ON/OFF AND PWM DIMMING June 2019 GENERAL DESCRIPTION FEATURES The IS32LT3128A is a programmable triple channel linear current regulator; two channels of up to 150mA each for LED lighting and a single channel of up to 30mA for illuminating switches. The device operates as a fully configurable theatrical dimming LED driver; no microcontroller is required. External resistors will program the current levels as well as the LED fade ON/OFF ramp rate. Additional configuration such as PWM source (internal or external), polarity (positive or negative) and switch type (momentary contact or latched) are selectable via the MODE1/2 pins.   An integrated debounce and latch circuit on the channel enable pin (EN1/2) is enabled when the device is configured for a momentary contact switch interface. The other option is to configure the EN pins to accept a static level signal for operation with latched switches. A VCC level PWM dimming signal can be connected to the PWM input pin to directly drive both LED channels. If configured for Internal-PWM-Dimming mode, the integrated PWM source will be triggered by a PWM pin voltage level. This enables LED dimming without the need for an external PWM input. The PWM input have a higher priority and will override the EN inputs. See Figure 60~66 for the details. The device integrates a 63 step fade ON/OFF algorithm (Gamma correction) which causes the output LED brightness to gradually ramp up to the full source value after the EN1/2 or PWM (when configured for Internal-PWM-Dimming mode) pins are triggered. The same controller causes the LED brightness to gradually ramp down to zero if the EN1/2 or PWM (when configured for Internal-PWM-Dimming mode) pins are triggered while the output channel is ON. The fade ramp can be interrupted mid-cycle before completion of the ramp cycle. The IS32LT3128A is targeted at the automotive market with end applications to include map and dome lighting as well as exterior accent lighting. For 12V automotive applications the low dropout driver can support 1 to 3 LEDs per channel. It is offered in a small thermally enhanced eTSSOP-20 package. Lumissil Microsystems – www.lumissil.com Rev.A, 05/06/2019       Operating voltage range, 5V to 42V Dual channel current sources - Individual programmable current via a single external resistor - Configurable from 20mA to 150mA Single channel 30mA (Max.) current source for switch illumination EN input supports either momentary contact or latched switch - Input is debounced and latched - Lower priority than PWM input - Gamma corrected Fade ON/OFF algorithm - Pull down resistors set independent fade ON and OFF ramp time Selectable external or internal PWM source - External PWM directly drives the current source - Internal 220Hz PWM source with Gamma corrected algorithm for automatic dimming the current source - Support both positive and negative polarity PWM Fault Protection: - Fault Reporting  LED strings short  Over temperature thermal shutdown - ISET pin shorted to GND - Over temperature current roll off AEC-Q100 Qualified Operating temperature range from -40°C ~ +125°C APPLICATIONS  Automotive Interior: - Map/Dome light - Puddle lamp in doors - Glove box light - Vanity mirror light 1 IS32LT3128A TYPICAL APPLICATION CIRCUIT VBattery 18 RPWM 10k PWM 50Hz~300Hz OUT1 OUT2 10 F 5 PWM OUT3 19 20 1 CPWM 3.3nF Backlight LED 2 4 Momentary Contact 3 12 13 14 RISET1 RISET2 RISET3 6 17 Figure 1 VCC EN3 EN1 FAULTB IS32LT3128A EN2 VIO ISET1 ISET2 ISET3 POL MODE1 MODE2 TSET_UP GND TSET_DN 7 8 Host RFAULTB 11 1 F 9 10 15 RTSET_UP 16 RTSET_DN Typical Application Circuit Configured for Momentary Contact Switch And External PWM Dimming VBattery 18 RPWM 10k High or Low Level OUT1 OUT2 10 F 5 PWM OUT3 19 20 1 CPWM 3.3nF Backlight LED 2 VCC 4 Latched Switch 3 12 13 14 RISET1 RISET2 RISET3 6 17 Figure 2 VCC EN3 EN1 FAULTB IS32LT3128A EN2 ISET1 ISET2 ISET3 VIO POL MODE1 MODE2 TSET_UP GND TSET_DN 7 8 Host RFAULTB 11 1 F 9 10 15 RTSET_UP 16 RTSET_DN Typical Application Circuit Configured for Latched Switch And Internal PWM Dimming Note 1: The resistor RPWM is a fixed 10kΩ, do not change value. CPWM is optional to minimize electromagnetic susceptibility. Lumissil Microsystems – www.lumissil.com Rev.A, 05/06/2019 2 IS32LT3128A PIN CONFIGURATION Package Pin Configuration (Top View) eTSSOP-20 Lumissil Microsystems – www.lumissil.com Rev.A, 05/06/2019 3 IS32LT3128A PIN DESCRIPTION No. Pin Description 1 OUT3 Max 30mA output current source for switch backlight LEDs. 2 EN3 Internally deglitch input pin for control of OUT3 current. Pull high (>VIH) to enable OUT3 current. Pull low (VIH) to either EN1 or EN2 will turn on the corresponding OUT1 or OUT2 currents. Grounding either EN1 or EN2 will turn off the corresponding OUT1 or OUT2 current. 11 POL Internally deglitched input pin for PWM polarity selection. Connect to VIO for PWM active high and grounded for PWM active low. 12~14 ISET1~ISET3 Output current setting for OUT1/2/3. Connect a resistor between this pin and GND to set the maximum output current. 15 TSET_UP Timing control for the Fade ON feature. Connect a resistor between this pin and GND to set the Fade ON time. Connect this pin directly to ground to disable the fade function for instant ON. 16 TSET_DN Timing control for the Fade OFF feature. Connect a resistor between this pin and GND to set the Fade OFF time. Connect this pin directly to ground to disable the fade function for instant OFF. 18 VCC Power supply input pin. 19,20 OUT1,OUT2 Max. 150mA output current source channels. Thermal Pad Connect to GND. Lumissil Microsystems – www.lumissil.com Rev.A, 05/06/2019 4 IS32LT3128A ORDERING INFORMATION Automotive Range: -40°C to +125°C Order Part No. Package QTY/Reel IS32LT3128A-ZLA3-TR eTSSOP-20, Lead-free 2500 Copyright  ©  2019  Lumissil  Microsystems.  All  rights  reserved.  Lumissil Microsystems reserves  the  right  to  make  changes  to  this  specification  and  its  products  at  any  time  without  notice.  Lumissil  Microsystems  assumes  no  liability  arising  out  of  the  application  or  use  of  any  information,  products  or  services described herein. Customers are advised to obtain the latest version of this device specification before relying on any published information and  before placing orders for products.  Lumissil Microsystems does not recommend the use of any of its products in life support applications where the failure or malfunction of the product can  reasonably be expected to cause failure of the life support system or to significantly affect its safety or effectiveness. Products are not authorized for use in  such applications unless Lumissil Microsystems receives written assurance to its satisfaction, that:  a.) the risk of injury or damage has been minimized;  b.) the user assume all such risks; and  c.) potential liability of Lumissil Microsystems is adequately protected under the circumstances Lumissil Microsystems – www.lumissil.com Rev.A, 05/06/2019 5 IS32LT3128A ABSOLUTE MAXIMUM RATINGS (NOTE 2) VCC, OUT1/2/3, PWM, EN1/2/3 VIO, POL, MODE1/2, ISET1/2/3, TSET_UP, TSET_DN, FAULTB Ambient operating temperature, TA=TJ Maximum continuous junction temperature, TJ(MAX) Storage temperature range, TSTG Package thermal resistance, junction to ambient (4 layer standard test PCB based on JESD 51-2A), θJA Package thermal resistance, junction to thermal PAD (4 layer standard test PCB based on JESD 51-8), θJP Maximum power dissipation, PDMAX ESD (HBM) ESD (CDM) -0.3V ~ +45V -0.3V ~ +7.0V -40°C ~ +125°C 150°C -65°C ~ +150°C 34°C/W 14.46°C/W 2.94W ±2kV ±750V Note 2: Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only and functional operation of the device at these or any other condition beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS TJ = -40°C ~ +125°C, VCC=12V, refer to each condition description. Typical values are at TJ = 25°C. Symbol Parameter VCC Supply voltage range VHR Minimum headroom voltage Condition tON IOUT_LIM IOUT EOUT EIOUTM tSL Quiescent supply current Typ. 5 Max. Unit 42 VCC -VOUT1/2, IOUT1/2= -150mA (Note 3) 900 VCC -VOUT1/2, IOUT1/2= -100mA (Note 3) 700 VCC -VOUT3, IOUT3= -30mA (Note 3) 900 OUT1/2/3 output current are all disabled ICC Min. 0.1 0.31 1 mV mA RISET1= RISET2 =RISET3=15kΩ, OUT1/2/3 output current are all enabled by ENx, but OUT1/2/3 are all floating 5.5 mA VCC=4.2V, OUT1/2 output current are all are enabled by EN1/2 (only for EN Low Pulse Mode), EN3 floating 0.25 mA Startup time VCC> 6V to IOUT