DS3881E+C Analog Devices

DS3881 Rev 1 8/07 Single-Channel Automotive CCFL Controller General Description Features Single-Channel CCFL Controller for Backlighting The DS3881 is a single-channel cold-cathode fluores- LCD Panels and Instrument Clusters in cent lamp (CCFL) controller for automotive applications Automotive Navigation/Infotainment Applications that provides up to 300:1 dimming. It is ideal for driving CCFLs used to backlight liquid crystal displays (LCDs) Minimal External Components Required in navigation and infotainment applications and for dri- 2 I C Interface ving CCFLs used to backlight instrument clusters. The Per-Channel Lamp-Fault Monitoring for Lamp- DS3881 is also appropriate for use in marine and avia- Open, Lamp-Overcurrent, Failure to Strike, and tion applications. Overvoltage Conditions The DS3881 features EMI suppression functionality and Status Register Reports Fault Conditions provides a lamp current overdrive mode for rapid lamp Accurate (5%) Independent On-Board Oscillators heating in cold weather conditions. The DS3881 sup- for Lamp Frequency (40kHz to 100kHz) and DPWM ports a single lamp configuration with fully independent Burst-Dimming Frequency (22.5Hz to 440Hz) lamp control and minimal external components. Lamp and DPWM Frequencies can be Multiple DS3881 controllers can be cascaded to sup- Synchronized with External Sources to Reduce port applications requiring more than one lamp. Control Visual LCD Artifacts in Video Applications of the DS3881, after initial programming setup, can be 2 Spread-Spectrum Lamp Clock Reduces EMI completely achieved through I C software communica- tion. Many DS3881 functions are also pin-controllable if Lamp Frequency can be Stepped Up or Down to Move EMI Spurs Out of Band software control is not desired. Lamp Current Overdrive Mode with Automatic Applications Turn-Off Quickly Warms Lamp in Cold Automotive LCDs Temperatures Instrument Clusters Analog or Digital Brightness Control Marine and Aviation LCDs 300:1 Dimming Range Possible Using the Digital Brightness Control Option Pin Configuration Programmable Soft-Start Minimizes Audible Transformer Noise TOP VIEW On-Board Nonvolatile (NV) Memory Allows Device A0 1 24 FAULT Customization SDA 2 23 GB1 8-Byte NV User Memory for Storage of Serial Numbers and Date Codes 3 22 SCL GA1 Low-Power Standby Mode LSYNC 4 21 V CC 4.75V to 5.25V Single-Supply Operation 5 20 LOSC PDN DS3881 Temperature Range: -40C to +105C 19 BRIGHT 6 LCO 24-Pin TSSOP Package 18 PSYNC 7 GND 17 POSC 8 STEP Ordering Information A1 9 16 N.C. PART TEMP RANGE PIN-PACKAGE 15 GND S 10 OVD1 DS3881E+ -40C to +105C 24 TSSOP (173 mils) SVML 11 14 LCM1 DS3881E+T&R -40C to +105C 24 TSSOP (173 mils) 13 SVMH 12 V CC +Denotes lead-free package. TSSOP Typical Operating Circuit appears at end of data sheet. Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com.Single-Channel Automotive CCFL Controller ABSOLUTE MAXIMUM RATINGS Voltage Range on V , SDA, and Operating Temperature Range .........................-40C to +105C CC SCL Relative to Ground.....................................-0.5V to +6.0V EEPROM Programming Temperature Range .........0C to +85C Voltage Range on Leads Other than V , SDA, and Storage Temperature Range .............................-55C to +125C CC SCL ......................-0.5V to (V + 0.5V), not to exceed +6.0V Soldering Temperature...................See J-STD-020 Specification CC Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. RECOMMENDED OPERATING CONDITIONS (T = -40C to +105C) A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Supply Voltage V (Note 1) 4.75 5.25 V CC V CC Input Logic 1 V 2.0 V IH + 0.3 Input Logic 0 V -0.3 1.0 V IL V + CC SVML/H Voltage Range V -0.3 V SVM 0.3 V + CC BRIGHT Voltage Range V -0.3 V BRIGHT 0.3 V + CC LCM Voltage Range V (Note 2) -0.3 V LCM 0.3 V + CC OVD Voltage Range V (Note 2) -0.3 V OVD 0.3 Gate-Driver Output Charge Q 20 nC G Loading ELECTRICAL CHARACTERISTICS (V = +4.75V to +5.25V, T = -40C to +105C.) CC A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Supply Current I G , G loaded with 600pF 12 mA CC A B Input Leakage (Digital Pins) I -1.0 +1.0 A L Power-Down Current I 1mA PDN Output Leakage (SDA, FAULT)I High impedance -1.0 +1.0 A LO Low-Level Output Voltage V I = 4mA 0.4 V OL OL (LSYNC, PSYNC) V I = 3mA 0.4 OL1 OL1 Low-Level Output Voltage V (SDA, FAULT) V I = 6mA 0.6 OL2 OL2 Low-Level Output Voltage V I = 4mA 0.4 V OL3 OL3 (GA1, GB1) High-Level Output Voltage V I = -1mA 2.4 V OH OH (LSYNC, PSYNC) 2 DS3881