DATASHEET ISL97672B FN7995 Rev.3.00 6-Channel LED Driver with Ultra Low Dimming Capability Sep 7, 2017 The ISL97672B is an integrated 6-channel power LED driver for Features LCD backlight applications. The ISL97672B is capable of 6 x 50mA channels driving LEDs with an input from 4.5V to 26.5V and a maximum output up to 45V. 4.5V to 26.5V input The ISL97672B employs an adaptive boost switching 45V output maximum architecture that allows direct PWM dimming with dimming Adaptive boost switching architecture duty cycle as low as 0.007% at 200Hz or 0.8% at 20kHz. PWM Direct PWM dimming with dimming linearity of Dimming frequency can be as high as 30kHz. 0.007%~100% at 200Hz or 0.8%~100% <20kHz The ISL97672B employs dynamic headroom control that Adjustable 200kHz to 1.4MHz switching frequency monitors the highest LED forward voltage string for output Dynamic headroom control regulation to minimize headroom voltage and power loss in a typical multi-string operation. Typical current matching Fault protections with latched flag indication between channels is 0.7%. - String open/short-circuit The ISL97672B incorporates extensive protection functions - Overvoltage Protection (OVP) that flag whenever a fault occurs. The protections include - Over-Temperature Protection (OTP) string-open and short-circuit detections, OVP, OTP, and an - Optional output short-circuit fault protection switch optional output short-circuit protection with external fault disconnect switch. Current matching 0.7% 20 Ld 3x4 QFN package The ISL97672B is offered in a compact 20 Ld QFN 3x4 package and can operate in ambient temperatures of -40C to Applications +85C. Notebook displays LED backlighting Related Literature LCD monitor LED backlighting For a full list of related documents, visit our website Multi-function printer scanning light source - ISL97672B product page V = 45V*, 6 x 50mA V = 4.5V~26.5V OUT IN Q1 OPTIONAL ISL97672B 1 FAULT LX 20 VIN 2 OVP 1.2 16 4 VDC 1.0 PGND 19 6 /FLAG 18 COMP 0.8 CH0 10 CH1 11 0.6 CH2 12 3 EN 0.4 CH3 13 PWM 5 CH4 14 I = 20mA LED 17 RSET 0.2 CH5 15 F = 20kHz PWM 8 FSW * V 12V IN 0.0 9 AGND 0 0.4 0.8 1.2 1.6 2.0 2.4 2.8 3.2 3.6 4.0 4.4 4.8 5.2 PWM DIMMING DUTY CYCLE (%) FIGURE 1. TYPICAL APPLICATION DIAGRAM FIGURE 2. DIMMING LINEARITY AT 20kHz FN7995 Rev.3.00 Page 1 of 17 Sep 7, 2017 I (mA) LEDISL97672B Block Diagram 45V*, 6x50mA V : 4.5V~26.5V IN 10H/1.5A FAULT 4.7F/50V VIN LX INTERNAL O/P SHORT EN BIAS OVP REG OVP FAULT VDC FLAG OSC AND RAMP COMP SUM = 0 FET LOGIC DRIVERS I MAX /FLAG ILIMIT PGND FAULT FLAG OPEN CKT, SHORT CKT DETECTION DYNAMIC 8-BIT HIGHEST VF COMP GM HEADROOM CH1 STRING DAC AMP CONTROL DETECT CH2 CH3 CH4 1 + CH5 2 - + CH6 REF - 3 GEN ISET 4 * V 1 2V IN 5 REF REF OVP VSC 6 + - PWM DIMMING CONTROLLER TEMP SENSOR ISL97672B FIGURE 3. ISL97672B BLOCK DIAGRAM Ordering Information PART NUMBER PACKAGE PKG. (Notes 1, 2, 3)PART MARKING (RoHS Compliant) DWG. ISL97672BIRZ 672B 20 Ld 3x4 QFN L20.3x4 NOTES: 1. Add -T suffix for 6k unit tape and reel option. Refer to TB347 for details on reel specifications. 2. These Intersil Pb-free plastic packaged products employ special Pb-free material sets, molding compounds/die attach materials, and 100% matte tin plate plus anneal (e3 termination finish, which is RoHS compliant and compatible with both SnPb and Pb-free soldering operations). Intersil Pb-free products are MSL classified at Pb-free peak reflow temperatures that meet or exceed the Pb-free requirements of IPC/JEDEC J STD-020. 3. For Moisture Sensitivity Level (MSL), please see device information page for ISL97672B. For more information on MSL, see TB363. FN7995 Rev.3.00 Page 2 of 17 Sep 7, 2017