IS31FL3235A 28 CHANNELS LED DRIVER August 2020 GENERAL DESCRIPTION FEATURES IS31FL3235A is comprised of 28 constant current 2.7V to 5.5V supply channels each with independent PWM control, I2C interface, automatic address increment designed for driving LEDs, PWM frequency can be function 3kHz or 22kHz. The output current of each channel Internal reset register can be set at up to 38mA (Max.) by an external resistor Modulate LED brightness with 256 steps PWM and independently scaled by a factor of 1, 1/2, 1/3 and Each channel can be controlled independently 1/4. The average LED current of each channel can be Each channel can be scaled independently by 1, changed in 256 steps by changing the PWM duty cycle 1/2, 1/3 and 1/4 through an I2C interface. PWM frequency selectable The chip can be turned off by pulling the SDB pin low or - 3kHz (Default) by using the software shutdown feature to reduce - 22kHz power consumption. -40C to +85C temperature range IS31FL3235A is available in QFN-36 (4mm 4mm) ESD HBM 8kV package. It operates from 2.7V to 5.5V over the QFN-36 (4mm 4mm) package temperature range of -40C to +85C. APPLICATIONS Mobile phones and other hand-held devices for LED display LED in home appliances TYPICAL APPLICATION CIRCUIT Figure 1 Typical Application Circuit Lumissil Microsystems www.lumissil.com 1 Rev. H, 08/20/2020 IS31FL3235A *Note 1 *Note 1 *Note 3 5V 31 5V 33 VCC 36 30 OUT1 1 F AD 91 0.1 F 1 OUT2 *Note 2 33 2 V OUT3 IH 4.7k 4.7k 34 SDA 35 Micro IS31FL3235A SCL Controller 29 SDB 100k 33 26 OUT26 33 91 R EXT 27 OUT27 REXT 3.3k 33 14 28 GND OUT28 32 Figure 2 Typical Application Circuit (V =5V) CC Note 1: V should be same as VCC voltage. LED+ Note 2: V is the high level voltage for IS31FL3235A, which is usually same as VCC of Micro Controller, e.g. if V of Micro Controller is 3.3V, IH CC V =3.3V. If V =5V and V is lower than 2.8V, recommend to add a level shift circuit. IH CC IH Note 3: These resistors are optional to help reduce the power of IS31FL3235A only (values are for V =5V). LED+ Note 4: The maximum global output current is set up to 23mA when R = 3.3k . The maximum global output current can be set by external EXT resistor, R . Please refer to the detail information in Page 11. EXT Note 5: The IC should be placed far away from the mobile antenna in order to prevent the EMI. Lumissil Microsystems www.lumissil.com 2 Rev. H, 08/20/2020