MAX8759EVKIT Maxim Integrated Products, MAX8759EVKIT Datasheet
MAX8759EVKIT
Specifications of MAX8759EVKIT
Related parts for MAX8759EVKIT
MAX8759EVKIT Summary of contents
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... Exposed pad. Pin Configuration appears at end of data sheet. SMBus is a trademark of Intel Corp. ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. ♦ Accurate Dimming Control Using SMBus, PWM Interface, or Ambient Light Sensor ♦ ...
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Low-Cost, SMBus, CCFL Backlight Controller ABSOLUTE MAXIMUM RATINGS BATT to GND..........................................................-0.3V to +30V BST1, BST2 to GND ...............................................-0.3V to +36V BST1 to LX1, BST2 to LX2 ........................................-0.3V to +6V FREQ GND .........................................-0.3V to +6V CC ...
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Low-Cost, SMBus, CCFL Backlight Controller ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 12V BATT CC PARAMETER IFB1, IFB2 Input Bias Current IFB1, IFB2 Lamp-Out Threshold IFB1, IFB2 to COMP Transconductance COMP Output Impedance COMP Discharge ...
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Low-Cost, SMBus, CCFL Backlight Controller ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 12V BATT CC PARAMETER Zero-Crossing Delay Maximum Zero-Crossing Delay DEL Disable Threshold TFLT Charge Current TFLT Trip Threshold SDA, SCL, Input Low Voltage ...
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Low-Cost, SMBus, CCFL Backlight Controller ELECTRICAL CHARACTERISTICS (Circuit of Figure 12V BATT CC PARAMETER BATT Input Voltage Range BATT Quiescent Current V Output Voltage, Normal Operation CC V Output Voltage, Shutdown CC V Undervoltage ...
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Low-Cost, SMBus, CCFL Backlight Controller ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 12V BATT CC PARAMETER PWMI Input Low Voltage PWMI Input High Voltage PWMI Input Frequency Range PWMI Brightness Setting ALS Full-Adjustment Range VALS ...
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Low-Cost, SMBus, CCFL Backlight Controller (Circuit of Figure 12V LOW-INPUT VOLTAGE OPERATION (V = 8.0V) IN MAX8759 toc01 10µs/div A: VFB, 2V/div C: LX2, 10V/div B: LX1, 10V/div D:IFB, 2V/div LINE TRANSIENT ...
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Low-Cost, SMBus, CCFL Backlight Controller (Circuit of Figure 12V OPEN-LAMP VOLTAGE LIMITING AND TIMEOUT MAX8759 toc010 200ms/div A: VFB, 2V/div C: TFLT, 5V/div B: COMP, 500mV/div DPWM FREQUENCY vs. R FREQ ...
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Low-Cost, SMBus, CCFL Backlight Controller (Circuit of Figure 12V NORMALIZED BRIGHTNESS vs. SMBus BRIGHTNESS AND PWMI DUTY CYCLE 100 80 SMB = 0xFF 0.2 0.4 PWMI DUTY ...
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Low-Cost, SMBus, CCFL Backlight Controller PIN NAME Supply Input. BATT is the input to the internal 5.35V linear regulator that powers the device. Bypass BATT 1 BATT to GND with a 0.1µF ceramic capacitor. 2 SDA SMBus Serial Data Input ...
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Low-Cost, SMBus, CCFL Backlight Controller PIN NAME 18 BST1 GH1 Gate-Driver Supply Input. Connect a 0.1µF capacitor from LX1 to BST1. 19 PGND1 Power Ground. PGND1 is the return for the GL1 gate driver. 20 GL1 Low-Side MOSFET NL1 Gate ...
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Low-Cost, SMBus, CCFL Backlight Controller INPUT VOLTAGE F1 7.5V TO 24V 2A 21 BATT C7 0.1µF 27 GND 11 DEL 0.47µF MAX8759 SMB_DATA 2 SDA SMB_CLOCK 3 SCL PWM INPUT 7 PWMI 8 PWMO ...
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Low-Cost, SMBus, CCFL Backlight Controller Typical Operating Circuit The MAX8759 typical operating circuit (Figure single-lamp CCFL backlight inverter for notebook com- puter TFT LCD panels. The input voltage range of the circuit is from 7.5V to 24V. ...
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Low-Cost, SMBus, CCFL Backlight Controller LINEAR BATT REGULATOR GND V CC RDY VALS OC COMP ISEC OC 1.21V IFB1 FW IFB2 FW MAX V ERROR REF AMP COMP 1000µA OC VFB 2.3V OV COMP DWPM 8-BIT FREQ OSC COUNTER SCL ...
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Low-Cost, SMBus, CCFL Backlight Controller PWMO BUFFER PWMI BUFFER ALS A OFFSET DIGITAL D POT FAULT/ ALS STATUS STATUS REGISTER REGISTER 0X02 0X04 SDA SCL Figure 3. MAX8759 SMBus and Ambient-Light-Sensor Input Block A simplified CCFL inverter circuit is shown ...
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Low-Cost, SMBus, CCFL Backlight Controller V BATT NH1 LX1 NL1 OFF (a) V BATT NH1 OFF T1 C2 LX1 NL1 ON (BODY DIODE TURNS ON FIRST) (b) Figure 4. Resonant Operation The second peak f is the ...
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Low-Cost, SMBus, CCFL Backlight Controller 1:N AC SOURCE ( SOURCE (b) Figure 5. Equivalent Resonant Tank Circuit AC lamp current is sensed with a resistor connected in series ...
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Low-Cost, SMBus, CCFL Backlight Controller Dimming Control The MAX8759 controls the brightness of the CCFL by “chopping” the lamp current on and off using a low-fre- quency (between 100Hz and 350Hz) DPWM signal. The frequency of the internal DPWM oscillator ...
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Low-Cost, SMBus, CCFL Backlight Controller Fault Protections Lamp-Out Protection For safety, the MAX8759 monitors the lamp-current feedback inputs (IFB1 and IFB2) to detect faulty or open CCFL tubes. As described in the Lamp-Current Regulation section, the voltage on IFB1 and ...
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Low-Cost, SMBus, CCFL Backlight Controller WRITE-BYTE FORMAT S ADDRESS WR — 7 BITS 1b SLAVE ADDRESS READ-BYTE FORMAT S ADDRESS WR ACK — 7 BITS 1b 1b SLAVE ADDRESS COMMAND BYTE: SELECTS WHICH REGISTER YOU ARE READING FROM SEND-BYTE FORMAT ...
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Low-Cost, SMBus, CCFL Backlight Controller LOW HIGH SMBCLK SMBDATA t t SU:STA HD:STA A = START CONDITION MSB OF ADDRESS CLOCKED INTO SLAVE LSB OF ADDRESS CLOCKED INTO SLAVE R/W ...
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Low-Cost, SMBus, CCFL Backlight Controller HIGH LOW SMBCLK SMBDATA t t SU:STA HD:STA A = START CONDITION MSB OF ADDRESS CLOCKED INTO SLAVE LSB OF ADDRESS CLOCKED INTO SLAVE R/W ...
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Low-Cost, SMBus, CCFL Backlight Controller Brightness Control Register [0x00] The brightness control register of the MAX8759 con- tains 8 bits and supports 256 brightness levels. A write- byte cycle to register 0x00 sets the brightness level if the inverter is ...
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Low-Cost, SMBus, CCFL Backlight Controller The relationships among these 3 control bits can be thought of as specifying an operating mode for the invert- er. The defined modes are shown in Table 4. Note that depending on the settings of ...
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Low-Cost, SMBus, CCFL Backlight Controller Identification Register [0x03] (POR = 0x01) The identification register contains two bit fields to denote the manufacturer and the silicon revision. The bit BIT 7 (R) BIT 6 (R) BIT 5 (R) MFG4 MFG3 MFG[4..0]: ...
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Low-Cost, SMBus, CCFL Backlight Controller ALS High-Limit Register [0x06] (POR = 0xFF) The value in this read-write register reflects the highest possible brightness value the inverter can set based on inputs from the ALS. Users can change this value so ...
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Low-Cost, SMBus, CCFL Backlight Controller using the following equation to set the desired maxi- mum RMS secondary voltage V LAMP(RMS) 2 × V LAMP RMS MAX ( ) where the 2.3V is the ...
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Low-Cost, SMBus, CCFL Backlight Controller The transformer core saturation should also be consid- ered when selecting the operating frequency. The pri- mary winding should have enough turns to prevent transformer saturation under all operating conditions. Use the following expression to ...
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Low-Cost, SMBus, CCFL Backlight Controller INPUT VOLTAGE F1 7.5V TO 21V 2A 1 BATT C7 0.1µF 27 GND 11 DEL 0.47µF MAX8759 SMB_DATA 2 SDA SMB_CLOCK 3 SCL PWM INPUT 7 PWMI 8 PWMO ...
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Low-Cost, SMBus, CCFL Backlight Controller 6) Ensure the feedback connections are short and direct. To the extent possible, IFB1, IFB2, VFB, and ISEC connections should be far away from the high- voltage traces and the transformer the extent ...
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Low-Cost, SMBus, CCFL Backlight Controller (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to www.maxim-ic.com/packages.) ______________________________________________________________________________________ Package Information 31 ...
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... Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. 32 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2007 Maxim Integrated Products Package Information is a registered trademark of Maxim Integrated Products, Inc ...