iW350 SSL Interface Controller for Analog (0-10V), PWM, and Resistor Dimming with Optocoupler Delay Elimination 1 Description The iW350 is a PWM signal generator that works with three different types of dimming inputs, 0-10V PWM dimming, 0-10V linear dimming or simple dimming using a single resistor to ground from the DIM pin. The iW350 auto detects the dimmer type connected. A PWM dimming type is directly used, while the 0-10V linear dimming and resistor dimming signals are converted into a 0%-100% PWM duty cycle that can then be used to provide a dimming signal to a primary- side LED driver such as the iW3636, removing the need for transformers or other driver circuitry. The output of the iW350 is optimized in such a way as to remove the impact of the non-linear delay typical of optocouplers. The iW350 offers a high level of flexibility by offering programmability for the maximum dimming voltage, minimum output duty cycle and the turn-off threshold voltage through external resistors. The output PWM frequency is also programmable from 100Hz to 5kHz through a single capacitor to ground. The input to the iW350 integrates the necessary current source to interface with both active and passive 0-10V dimmers without additional circuitry, while the output can drive an optocoupler to provide isolated dimming control from the secondary to the primary. 2 Features SOIC-8 package 15V to 60V operating voltage External resistor configuration 3-in-1 dimmer interface x Programmable max dimming voltage: 8.5V, 9V, x 0-10V PWM dimming 9.5V and 10V x 0-10V linear dimming x Programmable minimum duty cycle: 1%, 3%, 5% x Single resistor dimming and 10% Dimmer type - auto detect x Programmable turn-off threshold: 0.5V, 0.6V, 0.7V and 0.8V x PWM or DC input dimming signal Programmable PWM output frequency range: 100Hz- 0% to 100% PWM output 5kHz x 1% PWM duty cycle tolerance Integrated current source for driving 0-10V dimmer x Selectable frequency range via external capacitor Low power shutdown mode x Unique duty cycle drive to account for non-linear Integrated optocoupler driver for isolated applications optocoupler delay 3 Applications 0-10V LED dimming application 3-in-1 LED driver interface chip (0-10V linear, 0-10V PWM and R dimming) dimming LED driver application Product Summary Rev. 0.2 Preliminary 07-Mar-2019 www.dialog-semiconductor.com 1 of 6 2019 Dialog SemiconductoriW350 SSL Interface Controller for Analog (0-10V), PWM, and Resistor Dimming with Optocoupler Delay Elimination L V OUT N RTN 3-in-1 Dimming Control U2 0-10V PWM U1 iW350 iW3636 or V V CC IN OUTPUT V CC 10V DRV DIM 0-10V Analog 0V I V SENSE IN or SEL SD NTC/DIM2 V SENSE Resistive GND CF GND DIM1 PWM Figure 3.1 : iW350 Typical Application Circuit Product Summary Rev. 0.2 Preliminary 07-Mar-2019 www.dialog-semiconductor.com 2 of 6 2019 Dialog Semiconductor 3.3V LDO