DS3881E Maxim Integrated Products, DS3881E Datasheet
DS3881E
Related parts for DS3881E
DS3881E Summary of contents
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... LCO o 24-Pin TSSOP Package 18 GND 17 STEP 16 N.C. PART 15 OVD1 DS3881E+ 14 LCM1 DS3881E+T& +Denotes lead-free package system, provided that the system conforms to the I ______________________________________________ Maxim Integrated Products Features Ordering Information TEMP RANGE PIN-PACKAGE -40°C to +105°C 24 TSSOP (173 mils) -40°C to +105°C ...
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Single-Channel Automotive CCFL Controller ABSOLUTE MAXIMUM RATINGS Voltage Range SDA, and CC SCL Relative to Ground.....................................-0.5V to +6.0V Voltage Range on Leads Other than V CC SCL ......................-0. 0.5V), not to exceed +6.0V CC ...
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Single-Channel Automotive CCFL Controller ELECTRICAL CHARACTERISTICS (continued +4.75V to +5.25V -40°C to +105°C PARAMETER SYMBOL High-Level Output Voltage (GA, GB) UVLO Threshold: V Rising V CC UVLO Threshold: V Falling V CC UVLO Hysteresis ...
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Single-Channel Automotive CCFL Controller ELECTRICAL CHARACTERISTICS (See Figure +4.75V to +5.25V -40°C to +105°C, timing referenced PARAMETER SYMBOL SCL Clock Frequency Bus Free Time Between Stop and ...
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Single-Channel Automotive CCFL Controller (V = 5.0V +25°C, unless otherwise noted ACTIVE SUPPLY CURRENT vs. SUPPLY VOLTAGE 7.0 DPWM = 100% DPWM = 10% 6.5 DPWM = 50% 6.0 5.5 5.0 SVML< ...
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Single-Channel Automotive CCFL Controller (V = 5.0V +25°C, unless otherwise noted SOFT-START 16V INV 50µs 5. 50µs 5. 50µs 2.00V LCM 50µs 2.00V OVD 6 _____________________________________________________________________ Typical Operating Characteristics ...
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Single-Channel Automotive CCFL Controller PIN NAME 1, 9 A0, A1 Address Select Input. Determines I 2 SDA ata Inp utp ut SCL Serial Clock Input. I Lamp Frequency Input/Output. This ...
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Single-Channel Automotive CCFL Controller PDN LCO SDA SCL DEVICE A0/A1 INTERFACE CONFIGURATION AND GND_S CONTROL PORT FAULT LSYNC LAMP FREQUENCY INPUT/OUTPUT STEP STEP LAMP FREQUENCY UP OR DOWN LOSC 40kHz TO 100kHz EXTERNAL RESISTOR ...
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Single-Channel Automotive CCFL Controller CHANNEL ENABLE CHANNEL FAULT DIGITAL CONTROLLER DIMMING PWM SIGNAL 512 x LAMP FREQUENCY [20.48MHz ~ 51.20MHz] LAMP FREQUENCY [40kHz ~ 80kHz] Figure 2. Per Channel Logic Diagram Detailed Description The DS3881 uses a push-pull drive scheme ...
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Single-Channel Automotive CCFL Controller Shadowed EEPROM The DS3881 incorporates SRAM-shadowed EEPROM memory locations for all memory that needs to be retained during power cycling. At power-up, SEEB (bit 7 of the BLC register) is low, which causes the shadowed locations ...
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Single-Channel Automotive CCFL Controller RESISTOR-SET DIMMING CLOCK 2.0V ANALOG DIMMING CONTROL VOLTAGE 0.5V DPWM SIGNAL 22.5Hz TO 440Hz EXTERNAL RESISTOR SETS DPWM RATE Figure 3. DPWM Source Configuration Options Analog dimming changes the brightness by increasing or decreasing the lamp ...
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Single-Channel Automotive CCFL Controller ANALOG BRIGHTNESS 2.0V BRIGHT 0.5V PSYNC RESISTOR-SET LSYNC DIMMING FREQUENCY POSC RESISTOR-SET LOSC LAMP FREQUENCY BRIGHT PSYNC LSYNC N.C. POSC N.C. LOSC ANALOG BRIGHTNESS 2.0V BRIGHT 0.5V PSYNC LSYNC DIMMING CLOCK POSC (22.5Hz TO 440Hz) LOSC ...
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Single-Channel Automotive CCFL Controller At the beginning of each lamp burst, the DS3881 pro- vides a soft-start that slowly increases the MOSFET gate-driver duty cycle (see Figure 6). This minimizes the possibility of audible transformer noise that could result from ...
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Single-Channel Automotive CCFL 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 following ...
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Single-Channel Automotive CCFL Controller Figure 8 shows a flowchart of how the DS3881 controls and monitors each lamp. The steps are as follows: 1) Supply Check—The lamps do not turn on unless the DS3881 supply voltage is above 4.3V and ...
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Single-Channel Automotive CCFL Controller DEVICE AND INVERTER SUPPLIES AT PROPER LEVELS? RESET FAULT COUNTER AND FAULT OUTPUT FAULT_RT STATUS BIT STRIKE LAMP [RAMP AND REGULATE TO OVD THRESHOLD] IF LAMP REGULATION THRESHOLD IS MET RUN LAMP LAMP OVERCURRENT [REGULATE LAMP ...
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Single-Channel Automotive CCFL Controller EMI Suppression Functionality The DS3881 contains two electromagnetic interference suppression features: spread-spectrum modulation and lamp oscillator frequency stepping. The first is the abili spread the spectrum of the lamp frequency. By setting either SS0 ...
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Single-Channel Automotive CCFL Controller Table 2. Status Register 1 (SR1) [SRAM, E0h] POWER-UP BIT R/W NAME DEFAULT FAULT_RT FAULT_L STO_L OV_L LOUT_L ...
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Single-Channel Automotive CCFL Controller Table 4a. Soft-Start Protocol Registers (SSPx) [Shadowed-EEPROM, F0h, F1h, F2h, F3h] FACTORY SSP# ADDR DEFAULT SSP1 F0h 21h SSP2 F1h 43h SSP3 F2h 65h SSP4 F3h 77h Table 4b. MOSFET Duty Cycle (MDC)Codes for Soft-Start Settings ...
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Single-Channel Automotive CCFL Controller Table 5. Control Register 1 (CR1) [Shadowed-EEPROM, F4h] FACTORY BIT R/W NAME DEFAULT 0 R/W 0 LOCE 1 R/W 0 POSCS 2 R/W 0 LFSS 3 R/W 0 DPSS 4 R/W 0 RGSO 5 R/W 0 ...
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Single-Channel Automotive CCFL Controller Table 6. Control Register 2 (CR2) [Shadowed-EEPROM, F5h] BIT R/W DEFAULT NAME 0 R/W 0 UMWP 1 R/W 0 POSCR0 2 R/W 0 POSCR1 3 R/W 1 LSR0 4 R/W 0 LSR1 5 — 0 RSVD ...
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Single-Channel Automotive CCFL Controller Table 7. EMI Control Register (EMIC) [Shadowed-EEPROM, F6h] FACTORY BIT R/W NAME DEFAULT 0 R/W 0 SS0 1 R/W 0 SS1 2 R/W 0 SSM 3 RSVD 4 R/W 0 STEPE 5 R/W 0 ...
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Single-Channel Automotive CCFL Controller Table 8. Lamp Current Overdrive Control Register (LCOC) [Shadowed-EEPROM, F7h] FACTORY BIT R/W NAME DEFAULT 0 R/W 0 LCO0 1 R/W 0 LCO1 2 R/W 0 LCO2 3 R/W 0 LCOE 4 R/W 0 TO0 5 ...
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Single-Channel Automotive CCFL Controller 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. ...
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Single-Channel Automotive CCFL Controller Byte Read: A byte read is an 8-bit information transfer from the slave to the master plus a 1-bit ACK or NACK from the master to the slave. The 8 bits of information that are transferred ...
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Single-Channel Automotive CCFL Controller COMMUNICATIONS KEY WHITE BOXES INDICATE THE MASTER START ACK CONTROLLING SDA NOT SHADED BOXES INDICATE THE SLAVE IS STOP P N ACK CONTROLLING SDA REPEATED ...
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Single-Channel Automotive CCFL Controller Table 9. Transformer Specifications (as Used in the Typical Operating Circuit) PARAMETER Turns Ratio (Secondary/Primary) Frequency Output Power Output Current Primary DCR Secondary DCR Primary Leakage Secondary Leakage Primary Inductance Secondary Inductance Secondary Output Voltage Note ...
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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 © 2006 Maxim Integrated Products is a registered trademark of Dallas Semiconductor Corporation. ...