MAX8831 MAXIM [Maxim Integrated Products], MAX8831 Datasheet
MAX8831
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MAX8831 Summary of contents
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... Schottky diode detection, with the status of each fault monitored continually for readback through 2 the I C interface. The MAX8831 is available in a tiny 2mm x 2mm, 16-bump WLP package. Cell Phones PDAs Smartphones ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim's website at www ...
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High-Efficiency, White LED Step-Up Converter 2 with I C Interface in 2mm x 2mm WLP ABSOLUTE MAXIMUM RATINGS IN to GND ..............................................................-0.3V to +6. COMP to GND.....................................-0. SDA, SCL to GND.......................................-0. OUT, LX, ...
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High-Efficiency, White LED Step-Up Converter with I ELECTRICAL CHARACTERISTICS (continued 3.6V 0V 1.8V GND PGND DD PARAMETER LX Leakage Current V IN OSCILLATOR Operating Frequency Maximum Duty Cycle V LED1 ...
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High-Efficiency, White LED Step-Up Converter 2 with I C Interface in 2mm x 2mm WLP INTERFACE TIMING CHARACTERISTICS (V = 1.6V to 5.5V -40°C to +85°C, unless otherwise noted.) (Note PARAMETER SYMBOL ...
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High-Efficiency, White LED Step-Up Converter with 3.6V 1.8V 1µ OUT 5mA, unless otherwise noted.) LED3 LED4 LED5 CONVERTER EFFICIENCY vs. INPUT VOLTAGE (LED1 ...
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... LED1 LED2 MAX8831 toc11 200mV/div (AC-COUPLED) 20V/div 0V 1V/div (AC-COUPLED) 20mA/div 0mA 20mA/div = I = 25.25mA LED2 0mA 200ns/div SHUTDOWN RESPONSE MAX8831 toc13 20V/div 0V 200mA/div 0mA 20mA/div 20mA/div 0mA 40ms/div LED3-TO-LED5 CURRENT ACCURACY vs. INPUT VOLTAGE 1.50 LED1, LED2: 8 LEDs AT 25.25mA LED3 TO LED5: 9 LEDs 1. ...
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... MAX8831 toc21 2mA/div I 0mA LED3 t = 512ms RAMP-DOWN = 128ms = I = 25.25mA, LED1 LED2 LED1 RAMP-DOWN MAX8831 toc18 10mA/div 0mA 1s/div LED3 RAMP-DOWN MAX8831 toc20 2mA/div 0mA 1s/div LED3 BLINK TIMER + RAMP TIMER COMBINED MAX8831 toc22 2mA/div 0mA = 1024ms, RAMP-UP = 128ms, OFF 400ms/div 7 ...
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... OUT the step-up converter are shut down. OUT is high impedance during shutdown. Detailed Description The MAX8831 integrates a 60mA, 28V PWM DC-DC step-up converter with five low-dropout LED current reg- ulators for display and keypad backlighting in cell phones, PDAs, and other portable devices. The IC pro- vides up to 90% efficiency over the entire input voltage range of 2 ...
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... High-Efficiency, White LED Step-Up Converter with I IN UVLO AND BIAS GND COMP INTERFACE SDA SCL MAX8831 Figure 1. MAX8831 Functional Diagram _______________________________________________________________________________________ 2 C Interface in 2mm x 2mm WLP OSC PWM LOGIC REF SEL MIN 5mA CURRENT REGULATORS OUT OVP LX LX PGND ...
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... LED3, LED4, and LED5, with eight possible timing set- tings. The individual blink ON and blink OFF timers for each low-current regulator are also programmable, or these features can be disabled. See the MAX8831 I Registers section for details. The LED3, LED4, and LED5 low-current regulators can be powered from an alternate external source ...
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High-Efficiency, White LED Step-Up Converter with I Table 1. LED1, LED2 Programmable Current Levels and Register Values ILED_CNTRL I (mA) LED_ REGISTER VALUE 0x00 0.05 0x01 0.1 0x02 0.2 0x03 0.25 0x04 0.35 0x05 0.45 0x06 0.55 0x07 0.65 0x08 ...
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... V UVLO enters the shutdown state and disables its internal ref- erence. During shutdown, the MAX8831 holds all regis- ters in reset, the step-up converter and all LED current drivers are off, and supply current is reduced to 0.1µA (typ). LX and LED1–LED5 are high impedance when the step-up converter is off ...
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... OVP, or OSDD fault occurs, the IC enters standby mode, the step-up converter stops switching, and all the current regulators are shut down by clearing their ON/OFF control bits. Once standby occurs, the MAX8831 does not transition back to the ON state until the STAT2 register is read, clearing the fault indication, 2 and command enabling one or more current regulators is received ...
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High-Efficiency, White LED Step-Up Converter 2 with I C Interface in 2mm x 2mm WLP ENABLE BIT CLEARED FOR FAULTED LED_ STRING AND STAT1 REGISTER IS UPDATED WITH FAULT CONDITION. ENABLE BIT TSD OR OVP FAULT CLEARED FOR ALL LED_, ...
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... CONDITION SCL output. Each transmission consists of a START condition (Figure 6) sent by a master, followed by the MAX8831 7-bit slave address plus a R/W bit, a register address byte more data bytes, and finally a STOP condition (Figures 5 and 6). Both SCL and SDA remain high when the interface is not busy ...
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... The first byte of information is the command byte (Figure 10), which determines which register of the 2 C address MAX8831 written by the next byte, if received STOP condition is detected after the command byte is received, the MAX8831 takes no further action beyond storing the command byte. Any bytes received after the command byte are data bytes ...
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... AS BYTE LAST DATA BYTE AM AM bytes from the MAX8831, by first writing the read com- mand (0x9B) to the MAX8831 (Figures 12 and 13). When performing read-after-write verification, reset the command byte’s address since the stored byte address is autoincremented after the write. The MAX8831 contains 19 registers that are accessible through the I descriptions for more details ...
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... LED_ Status Registers The LED_ status registers (STAT1, STAT2) indicate the fault conditions of the MAX8831 IC and LEDs and are read-only registers. The STAT1 register indicates a fault condition for each LED_ string, whether a shorted or open LED_ fault is causing the fault condition. The sec- ...
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... Higher value capacitors can reduce input and output ripple, but at the expense of size and higher cost. The high switching frequency of the MAX8831 demands a high-speed rectification diode for optimum efficiency. A Schottky diode is recommended due to its fast recovery time and low forward voltage drop. Ensure that the diode’ ...
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... High-Efficiency, White LED Step-Up Converter 2 with I C Interface in 2mm x 2mm WLP Table 3. MAX8831 Register Map COMMAND/ REGISTER ADDRESS BYTE (HEX) ON/OFF_CNTL 0x00 LED1_RAMP_CNTL 0x03 LED2_RAMP_CNTL 0x04 LED3_RAMP_CNTL 0x05 LED4_RAMP_CNTL 0x06 LED5_RAMP_CNTL 0x07 ILED1_CNTL 0x0B ILED2_CNTL 0x0C ILED3_CNTL 0x0D ILED4_CNTL 0x0E ILED5_CNTL ...
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High-Efficiency, White LED Step-Up Converter with I Table 4. ON/OFF_CNTL Register (Address 0x00) BIT NAME B7 (MSB) — Reserved for future use B6 — Reserved for future use B5 — Reserved for future use 0 = Disable LED5 current regulator ...
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High-Efficiency, White LED Step-Up Converter 2 with I C Interface in 2mm x 2mm WLP Table 6. ILED#_CNTL Registers for LED1, LED2 (Addresses: 0x0B, 0x0C) BIT NAME DESCRIPTION B7 (MSB) — Reserved for future use Programs LED# ...
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High-Efficiency, White LED Step-Up Converter with I Table 9. BOOST_CNTL Register (Address: 0x1D) BIT NAME B7 (MSB) — Reserved for future use B6 — Reserved for future use B5 — Reserved for future use 0 = LED5 is powered fr ...
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... Keep traces short, direct, and wide. Keep noisy traces, such as the LX node trace, away from sensitive analog circuitry. For improved thermal performance, maximize the copper area of the LX and PGND traces. Refer to the MAX8831 EV Kit for an example layout. 24 ______________________________________________________________________________________ Table 12. CHIP_ID1 Register ...
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... 10μH 2.7V TO 5.5V C1 1μ SCL SDA 1.6V TO 5.5V C3 0.1μF COMP C4 0.22μF Figure 15. MAX8831 Applications Circuit ______________________________________________________________________________________ 2 C Interface in 2mm x 2mm WLP D1 D2–D9 OUT C2 1μF MAX8831 PGND PGND DD LED1 LED2 LED3 LED4 LED5 GND D10–D17 D18–D26 D27– ...
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... I C Interface in 2mm x 2mm WLP VIN 10μH 2.7V TO 5.5V 1μ 1.6V TO 5.5V 0.1μF 0.22μF 26 ______________________________________________________________________________________ V OUT UP TO 28V LX OUT LX 1μF MAX8831 IN PGND PGND SCL SDA V DD LED1 LED2 LED3 COMP LED4 LED5 GND PROCESS: BiCMOS Typical Operating Circuit 5.0mA/LED 25 ...
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... High-Efficiency, White LED Step-Up Converter with I Pin Configuration TOP VIEW (BUMPS ON BOTTOM MAX8831 LED1 GND LED3 LED2 LED4 LED5 SDA PGND PGND WLP Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied ...