IS32BL3556-ZLA3

ISD(uA) 10
LED 4
Vdd(V) 4.75-40V
Solder Lead-free (RoHS Compliant)
Status S=NOW
IOUT(mA) 120mA per channel
Pkg Pin(mm) eTSSOP-20
Document Eval Board
Temp.Range Automotive Grade (-40C to +125°C)
Type 3556
Product Type BL = White LED Driver for LCD Backlight
Intensity Ctrl. PWM
Product Family 32 = Automotive Analog and Mixed Signal
Type of Driver Boost
Package Type Z = TSSOP
Solder Type L = Lead-free (RoHS Compliant)
Part Number 3556 = 3556
Temperature Grade A3 = Automotive temp. (-40°C to 125°C)
Package option blank = Tray or Tube

IS32BL3556-ZLA3 Features

  • Excellent input voltage transient response
  • Sync function to synchronize boost converter switching frequency up to 2.3MHz, allowing operation above the AM band
  • Single resistor primary OVP minimizes VOUT leakage
  • Fully integrated LED current sinks and boost converter up to 55V
  • LED current of 120mA per channel
  • 1% LED to LED matching accuracy
  • Internal secondary OVP for redundant protection
  • Drives up to 12 series LEDs in 4 parallel strings
  • 10000:1 PWM dimming at 100Hz
  • PWM and analog dimming inputs
  • Provides driver for external PMOS input disconnect switch
  • Built-in protection features:
  • - Shorted boost switch - Shorted FSET or ISET resistor - Shorted output - Open or shorted LED - Open boost Schottky - Over temperature (OTP)
  • AEC-Q100 qualified (pending)
  • LCD Monitor
  • LCD Display Module
  • LCD TV
  • Car infotainment

Overview

The IS32BL3556 is a step-up controller with an integrated switching FET for driving white LED arrays in LCD panel backlight applications. The boost controller is a current mode, fixed frequency architecture with the switching frequency set by an external resistor. The integrated boost controller generates the minimum output voltage to keep all LEDs illuminated at the set current. The current in each of the 4 channels is programmed to a specific value with an external current set resistor and matched to within 1%. LED dimming is achieved using an external digital PWM signal to either adjust the internal ISET current or pulse-width-modulate the LED intensity. The LED sinks have a fast response to a PWM input making it possible to achieve a high contrast ratio of 10,000:1. A synchronization pin can be used to synchronize multiple IS32BL3556 devices or to synchronize with the external PWM source in the range of 580 kHz to 2.3MHz. The high switching frequency allows the IS32BL3556 to operate above the AM radio band. The IS32BL3556 integrates a control block to drive an external P-Channel FET to disconnect the input supply from the system whenever a fault is detected. It has safety protection features to prevent damage during fault conditions. Protection features include output short and overvoltage, open or shorted diode, open or shorted LED pin, shorted boost switch, shorted FSET or ISET resistor, and IC over temperature. A dual level cycle-by-cycle current limit function provides soft start and protects the internal current switch against high current overloads. The IS32BL3556 is available in a thermally enhanced eTSSOP-20 package.