DS3882E+C Maxim Integrated Products, DS3882E+C Datasheet

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... Single-Supply Operation PDN ♦ Temperature Range: -40°C to +105°C LCO ♦ 28-Pin TSSOP Package GND STEP N.C. OVD1 PART LCM1 DS3882E+C GB1 DS3882E+T&R/C GA1 + Denotes a lead(Pb)-free/RoHS-compliant package. T&R = Tape and reel. ______________________________________________ Maxim Integrated Products Features Ordering Information TEMP RANGE PIN-PACKAGE -40° ...

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Dual-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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Dual-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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Dual-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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Dual-Channel Automotive CCFL Controller (V = 5.0V +25°C, unless otherwise noted ACTIVE SUPPLY CURRENT vs. SUPPLY VOLTAGE 8.0 DPWM = 100% 7.5 DPWM = 10% DPWM = 50% 7.0 6.5 6.0 5.5 SVML< 2V 5.0 4.5 ...

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Dual-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 STAGGERED BURST DIMMING START 0.2ms ...

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Dual-Channel Automotive CCFL Controller PINS BY CHANNEL (n) NAME MOSFET A Gate Drive. Connect directly to logic-level mode n-channel MOSFET. Leave open if channel GAn unused. MOSFET B Gate Drive. Connect directly to ...

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Dual-Channel Automotive CCFL Controller NAME PIN DPWM Oscillator Resistor Adjust. A resistor to ground on this lead sets the frequency of the DPWM POSC 9 oscillator. This lead can optionally accept a 22.5Hz to 440Hz clock that will become the ...

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Dual-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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Dual-Channel Automotive CCFL Controller CHANNEL ENABLE CHANNEL FAULT DIGITAL CCFL 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 DS3882 uses a push-pull drive ...

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Dual-Channel Automotive CCFL Controller Shadowed EEPROM The DS3882 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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Dual-Channel Automotive CCFL Controller non-zero PWM code to the BPWM register disables the 2 BRIGHT pin and enables I C burst dimming control. Setting the 7-bit PWM code to 0000001b causes the DS3882 to operate with the minimum burst duty ...

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Dual-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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Dual-Channel Automotive CCFL Controller Configuring Systems with Multiple DS3882s The source and receiver options for the lamp frequency clock and DPWM signal allow multiple DS3882s to be synchronized in systems requiring more than two lamps. The lamp and dimming clocks ...

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Dual-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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Dual-Channel Automotive CCFL Controller Figure 8 shows a flowchart of how the DS3882 controls and monitors each lamp. The steps are as follows: 1) Supply Check—The lamps do not turn on unless the DS3882 supply voltage is above 4.3V and ...

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Dual-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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Dual-Channel Automotive CCFL Controller EMI Suppression Functionality The DS3882 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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Dual-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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Dual-Channel Automotive CCFL Controller Table 3. Status Register 2 (SR2) [SRAM, E1h] POWER-UP BIT R/W NAME DEFAULT FAULT_RT FAULT_L STO_L OV_L LOUT_L ...

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Dual-Channel Automotive CCFL Controller Table 5a. 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 5b. MOSFET Duty Cycle (MDC)⎯Codes for Soft-Start Settings ...

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Dual-Channel Automotive CCFL Controller Table 6. 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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Dual-Channel Automotive CCFL Controller Table 7. 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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Dual-Channel Automotive CCFL Controller Table 8. 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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Dual-Channel Automotive CCFL Controller Table 9. 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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Dual-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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Dual-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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Dual-Channel Automotive CCFL Controller COMMUNICATIONS KEY WHITE BOXES INDICATE THE MASTER IS S START A ACK CONTROLLING SDA NOT SHADED BOXES INDICATE THE SLAVE IS STOP P N ACK CONTROLLING SDA REPEATED ...

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Dual-Channel Automotive CCFL Controller Table 10. Transformer Specifications (as Used in the Typical Operating Circuit ) PARAMETER Turns Ratio (Secondary/Primary) (Notes Frequency Output Power Output Current Primary DCR Center tap to one end Secondary DCR Primary Leakage ...

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Dual-Channel Automotive CCFL Controller SDA SCL CONFIGURATION AND CONTROL PORT GND_S R11 FAULT LAMP CURRENT LCO OVERDRIVE ENABLE HARDWARE PDN LAMP ON/OFF CONTROL LAMP BRIGHTNESS BRIGHT STEP ...

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