STEVAL-ISA056V1 STMicroelectronics

STEVAL-ISA056V1 6 rows - 30 mA LEDs driver with boost converter for LCD panels backlight evaluation board based on the PM6600 Data Brief Features Boost section 4.5 V to 28 V input voltage range Internal Power MOSFET Internal +5 V LDO for device supply Up to 36 V output voltage Constant frequency peak current-mode ctrl 200 kHz to 1 MHz adjustable switching frequency External sync for multi-device application Pulse-skip power saving mode at light load Programmable soft-start STEVAL-ISA056V1 Programmable OVP protection Single ceramic output capacitor managed). The device allows to detect and Latched thermal shutdown manage the open and shorted LED faults and to let unused rows floating. Basic protections Backlight driver section (output over-voltage, internal MOSFET over- Six rows with 30mA maximum current current and thermal shutdown) are provided. capability (adjustable) Up to 10 W LEDs per row Rows disable option Less than 500 ns minimum dimming time (1% minimum dimming duty-cycle at 20 kHz dimming frequency) 2.0% current matching between rows LED failure (open and short circuit) detection Description This evaluation board based on the PM6600 consists of a high efficiency monolithic boost converter and six controlled current generators (rows) specifically designed to supply LEDs arrays used in the backlight of LCD panels. The device can manage an output voltage up to 36 V (i.e. ten white-LEDs per row). The generators can be externally programmed to sink up to 30 mA and can be dimmed via a PWM signal (1% dimming duty-cycle at 20 kHz can be March 2008 Rev 1 1/4 For further information contact your local STMicroelectronics sales office. www.st.com 4 Obsolete Product(s) - Obsolete Product(s)Circuit schematic STEVAL-ISA056V1 1 Circuit schematic Figure 1. Schematic 2/4 Obsolete Product(s) - Obsolete Product(s) D1 VVBOOSBOOST VININ+ L1 6u8 C1 STPPSS1L40M TP7 10u VIN R1 C13 R8 510k 22p 68080k SYNC SSLOPLOPE AVAVCC AVCC J2 C2 C3 C4 AVAVCC R11 1k2 2 1 2u2 2u2 NN..M. OVSEOVSEL R2 C10 U1 LED EN 16k 56060p D2 R9 11000k C6 10100n RED, D, 3mA 6 18 AVCC OOVSEVSEL R4 9 FAULT 4R7 SLOPE GND R13 C12 C5 1u NM NM 7 17 LDO5 PPGGND TP8 EN 22 8 FAULT R12 D3 7 NM NM 21 PM6660600 16 6 EN ROW6 15 5 ROW5 20 14 4 DIDIM DIDIM ROW4 13 3 ROW3 5 12 2 MODE ROW2 AAVVCC 11 1 ROW1 COMP 1 25 COMP THPD J8 SW2 24 HEEAADERR 8 SS SS R3 C11 SW3 2k4 R10 MODE 4n7 RES C7 AVAVCC ROW1 ROW2 ROW3 ROW4 ROW5 ROW6 100k FSW RIRILIM 3n3 BILIM C9 C8 TP13 4n7 N.N.M. R6 R7 R5 33330k SW1 180k 51k FSW VININ- 4 FSW 23 SYSYNC 2 RRIILIM 8 VIN 3 BILIM 10 19 SSGGND LX