DS3994Z+W Maxim Integrated Products, DS3994Z+W Datasheet
DS3994Z+W
Specifications of DS3994Z+W
Related parts for DS3994Z+W
DS3994Z+W Summary of contents
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... SO (300 mils) Package SCL SDA OVD4 LCM4 PART GB4 DS3994Z+ GA4 + Denotes a lead-free package. OVD3 LCM3 GB3 GA3 V CC GND Typical Operating Circuits appear at end of data sheet. ______________________________________________ Maxim Integrated Products Features Ordering Information TEMP RANGE PIN-PACKAGE -40°C to +85°C 28 SO-300 1 ...
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Cold-Cathode Fluorescent Lamp Controller ABSOLUTE MAXIMUM RATINGS Voltage Range SDA, and SCL CC Relative to Ground.............................................-0.5V to +6.0V Voltage Range on Leads Other than V CC SDA, and SCL…………………………..-0. Stresses beyond those listed under ...
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ELECTRICAL CHARACTERISTICS (continued +4.5V to +5.5V -40°C to +85°C PARAMETER SYMBOL High-Level Output Voltage (GA, GB) UVLO Threshold—V Rising V CC UVLO Threshold—V Falling V CC UVLO Hysteresis V SVM Falling Edge Threshold SVM ...
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Cold-Cathode Fluorescent Lamp Controller ELECTRICAL CHARACTERISTICS (See Figure 10 +4.5V to +5.5V, timing referenced PARAMETER SYMBOL SCL Clock Frequency Bus Free Time Between Stop and Start Conditions Hold Time (Repeated) ...
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T = +25°C, unless otherwise noted ACTIVE SUPPLY CURRENT vs. SUPPLY VOLTAGE DPWM = 100% DPWM = 50% 7 DPWM = 10 SVM < 2V GATE Q = 3.5nC f ...
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Cold-Cathode Fluorescent Lamp Controller (V = +5.0V +25°C, unless otherwise noted BURST DIMMING AT 150Hz AND 50% 1ms 5. 1ms 5. 1ms 2.0V LCM 1ms 1.0V OVD LAMP STRIKE WITH OPEN ...
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PINS BY CHANNEL (n = 1–4) NAME GAn GBn LCMn OVDn NAME PIN GND 15 Ground Connection V 16 Power-Supply Connection CC ...
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Cold-Cathode Fluorescent Lamp Controller SDA DEVICE I SCL CONFIGURATION COMPATIBLE PORT A0 INTERFACE FAULT LAMP FREQUENCY LSYNC INPUT/OUTPUT EXTERNAL RESISTOR LAMP FREQUENCY SET LOSC DPWM SIGNAL PSYNC INPUT/OUTPUT ANALOG BRIGHTNESS BRIGHT CONTROL EXTERNAL RESISTOR POSC DPWM ...
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CHANNEL ENABLE CHANNEL FAULT DIGITAL CCFL CONTROLLER DIMMING PWM SIGNAL 512 x LAMP FREQUENCY [10.24MHz ~ 40.96MHz] LAMP FREQUENCY [20kHz ~ 80kHz] Figure 1. Per Channel Logic Diagram Detailed Description The DS3994 uses a push-pull drive scheme to convert a ...
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Cold-Cathode Fluorescent Lamp Controller Channel Phasing The lamp-frequency MOSFET gate turn-on times are equally phased among the four channels during the burst period. This reduces the inrush current that would result from all lamps switching simultaneously, and hence eases ...
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RESISTOR-SET DIMMING CLOCK 2.0V OR 3.3V 0.5V ANALOG DIMMING OR CONTROL VOLTAGE 0.0V DPWM SIGNAL 22.5Hz TO 440Hz RESISTOR TO SET THE DIMMING FREQUENCY Figure 3. DPWM Source Configuration Options Table 1. BRIGHT Analog Dimming Input Slope and Voltage Range ...
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Cold-Cathode Fluorescent Lamp Controller When the DPWM signal is provided by an external source, either from the PSYNC pin of another DS3994 or from some other user-generated source input into the PSYNC I/O pin of the DS3994. ...
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Lamp Strike Frequency Boost The DS3994 also features a programmable lamp strike frequency boost option. During the strike period, the transformer secondary is essentially unloaded. The lamp frequency be can be easily increased causing a higher strike voltage. The SB0/1/2 ...
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Cold-Cathode Fluorescent Lamp Controller ANALOG BRIGHTNESS 2.0V OR 3.3V BRIGHT 0.5V OR 0.0V PSYNC RESISTOR-SET LSYNC DIMMING FREQUENCY POSC RESISTOR-SET LOSC LAMP FREQUENCY BRIGHT PSYNC LSYNC POSC LOSC ANALOG BRIGHTNESS 2.0V OR 3.3V BRIGHT 0.5V OR 0.0V PSYNC LSYNC ...
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DPWM SIGNAL 22.5Hz TO 440Hz LAMP CURRENT SOFT-START LAMP CYCLE 1 2 GAn/GBn MOSFET GATE DRIVERS SOFT-START PROFILE WITH INCREASING MOSFET PULSE WIDTHS OVER A 16 LAMP CYCLE PERIOD RESULTS IN A LINEAR RAMP IN LAMP CURRENT. LAMP CURRENT Figure ...
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Cold-Cathode Fluorescent Lamp Controller Setting the Lamp and Dimming Clock (DPWM) Frequencies Using External Resistors Both the lamp and dimming clock frequencies can be set using external resistors. The resistance required for either frequency can be determined using the ...
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Figure 9 shows a flowchart of how the DS3994 controls and monitors each lamp. The steps are as follows: 1) Supply Check—The lamps will not turn on unless the DS3994 supply voltage is ≥ 4.5V and the voltage at the ...
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Cold-Cathode Fluorescent Lamp Controller DEVICE AND INVERTER SUPPLIES AT PROPER LEVELS? RESET FAULT COUNTER AND FAULT OUTPUT STRIKE LAMP [RAMP AND REGULATE TO OVD THRESHOLD] IF LAMP REGULATION THRESHOLD IS MET RUN LAMP LAMP OVERCURRENT [REGULATE LAMP [INSTANTANEOUS IF ...
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Detailed Register Descriptions The DS3994’s register map is shown in Table 4. Detailed register and bit descriptions follow in the sub- sequent tables. Table 4. Register Map BYTE BYTE FACTORY ADDRESS NAME DEFAULT* F0h Reserved 21h F1h Reserved 43h F2h ...
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Cold-Cathode Fluorescent Lamp Controller F4h: Control Register 1 (CR1) BIT NAME Lamp Overcurrent 0 LOC 0 = Lamp overcurrent detection disabled Lamp overcurrent detection enabled. POSC Select. See POSCR0 and POSCR1 bits in Control Register 2 to ...
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F5h: Control Register 2 (CR2) BIT NAME User Memory Write Protect 0 UMWP 0 = User Memory Write Access Blocked 1 = User Memory Write Access Permitted DPWM Oscillator Range Select. When using an external source for the dimming clock, ...
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Cold-Cathode Fluorescent Lamp Controller FCh: Control Register 3 (CR3) BIT NAME BRIGHT Analog Dimming Slope Select 0 SLOPE 0 = Positive Slope 1 = Negative Slope LST1 1 LST0 LST1 1 Note: The strike frequency ...
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The following terminology is commonly used to 2 describe I C data transfers. Master Device: The master device controls the slave devices on the bus. The master device generates SCL clock pulses, start, and stop conditions. Slave Devices: Slave devices ...
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Cold-Cathode Fluorescent Lamp Controller Byte Write: A byte write consists of 8 bits of informa- tion transferred from the master to the slave (most sig- nificant bit first) plus a 1-bit acknowledgement from the slave to the master. The ...
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COMMUNICATIONS KEY WHITE BOXES INDICATE THE MASTER IS S START A ACK CONTROLLING SDA NOT SHADED BOXES INDICATE THE SLAVE IS P STOP N ACK CONTROLLING SDA REPEATED START WRITE A ...
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Cold-Cathode Fluorescent Lamp Controller Table 5. Transformer Specifications PARAMETER Turns Ratio (Secondary/Primary) (Notes Frequency Output Power Output Current Primary DCR Center tap to one end Secondary DCR Primary Leakage Secondary Leakage Primary Inductance Secondary Inductance Center ...
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ANALOG BRIGHTNESS BRIGHT EXTERNAL DIGITAL PWM INPUT/ PSYNC INTERNAL DIGITAL PWM OUTPUT EXTERNAL LAMP FREQUENCY INPUT/ LSYNC INTERNAL LAMP FREQUENCY OUTPUT LOSC POSC FAULT SDA CONFIGURATION PORT SCL A0 NOTE 1: ONLY ONE ...
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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. 28 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2007 Maxim Integrated Products is a registered trademark of Dallas Semiconductor Corporation ...