MSL3088-IU Atmel, MSL3088-IU Datasheet
MSL3088-IU
Specifications of MSL3088-IU
Related parts for MSL3088-IU
MSL3088-IU Summary of contents
Page 1
... The advanced integrated PWM circuitry allows up to 4095:1 dimming, and offers simple PWM dimming control. The MSL3086 uses a single PWM input to control the LED dimming signals. The MSL3088 has two inputs, one for frequency and the other for duty cycle. Additionally, internal registers, available through the I C interface, optionally control PWM dimming frequency and/or duty cycle ...
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... Pin Descriptions .......................................................................................... 4 3.0 Absolute Maximum Ratings ....................................................................... 5 4.0 Electrical Characteristics ........................................................................... 6 5.0 Typical Operating Characteristics ............................................................. 7 6.0 Block Diagram ........................................................................................... 10 7.0 Typical Application Circuit ....................................................................... 11 8.0 Detailed Description ................................................................................. 12 8.1 Differences between the MSL3086 and MSL3088 ........................................................12 8.2 Operating the MSL3086/88 ...........................................................................................12 8.3 Boost Regulator Overview .............................................................................................13 8.4 Error Amplifier ................................................................................................................13 8.5 Gate Driver ....................................................................................................................14 8.6 Soft-Start .......................................................................................................................14 8.7 Boost Fault Monitoring and Protection ..........................................................................14 8.8 LED Current Regulators and PWM Dimming Modes ....................................................14 8 ...
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... LED Drivers with Integrated Boost Controller and Phase Shifted Dimming S LED D HIFTED IMMING SIGNALS GATE 2 17 PGND 3 MSL3088 16 ILED (TOP VIEW CGND 5 14 PWM 6 13 STR7 GATE 17 PGND 16 ILED 15 CGND 14 PWM 13 STR7 Atmel MSL3086/MSL3088 Datasheet 3 ...
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... Connect large copper ground plane for best thermal and electrical performance. C compatible serial interface; see the MSL3040/50/60/80/86/87/88/89 Programming Guide for information. 2 Atmel MSL3086/MSL3088 Datasheet 8-String 60mA LED Drivers with Integrated Boost Controller and Phase Shifted Dimming , set the un-optimized ...
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... Storage Temperature Range ............................................................................. -65°C to +125°C Lead Soldering Temperature, 10s .....................................................................................+300° .................................. -40°C to +85°C A MIN MAX ), 4-Layer (Note 8) .................................... 29°C 2-Layer (Note 8) .................................... 38°C .................................................................... 8.6°C/W JC 8-String 60mA LED Drivers with Integrated Boost Controller and Phase Shifted Dimming Atmel MSL3086/MSL3088 Datasheet 5 ...
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... R = 100kΩ ILED STRn String to average of all strings V = 60mA STRn MSL3086 1.0kΩ SCTH MSL3088, scThrshLvl[1: FBO DAC = 0xFF Temperature Rising, 10°C Hysteresis C = 1nF GATE At factory set boost frequency f = 350kHz to 1MHz (contact factory for boost frequencies different BOOST from 625kHz) ...
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... BOOST NOT SWITCHING sleep = slpPwrSv = 0 BOOST NOT SWITCHING sleep = slpPwrSv = 4.6 4.6 4.7 4.7 4.8 4.8 4.9 4.9 5.0 5.0 5.1 5.1 5.2 5.2 5.3 5.3 5.4 5.4 5.5 V ( CH3 = V , CH4 = I LED STRx PWR BOOST WAVEFORMS 10% LED DUTY CYCLE , CH2 = V , CH3 = I GATE INDUCTOR BOOST WAVEFORMS Atmel MSL3086/MSL3088 Datasheet 100% LED DUTY CYCLE 5.5 7 ...
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... LED Drivers with Integrated Boost Controller and Phase Shifted Dimming , CH3 = I GATE INDUCTOR BOOST WAVEFORMS 100% LED DUTY CYCLE , CH3 = I GATE INDUCTOR EXTERNAL SYNC AND PWM MSL3088 , CH2 = V , CH3 = V PWM STR0 MSL3088 , CH2 = V , CH3 = V PWM STR0 Atmel MSL3086/MSL3088 Datasheet 8 ...
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... PWM rising. Also shown is the string power supply output (VLED), which shows little disturbance. For this photo string 0 is enabled with all other strings disabled. Page 8-String 60mA LED Drivers with Integrated Boost Controller and Phase Shifted Dimming DRIVER RISE TIME Atmel MSL3086/MSL3088 Datasheet 9 ...
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... REG C1 PVIN C2 C3 FREQ SET DUTY CYCLE SET PWM SCTH (SYNC) CGND FLTB SCL SDA ILED R GND ILED Figure 1. MSL3086/MSL3088 Block Diagram © Atmel Inc., 2011. All rights reserved. MSL3086/MSL3087/MSL3088 Datasheet OUT1 R CS GATE CS EFFICIENCY OPTIMIZER DAC ...
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... LED current for all strings. The MSL3086/87/88 support PWM LED dimming up to 4095:1 and feature automatic phase shifted dimming, and dimming synchronized with external digital signals. The MSL3088 features independent frequency and duty cycle control inputs. All devices feature optional register-set PWM dimming, fault and ...
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... LED Current” beginning on page 16), supply a PWM control signal to the PWM input (MSL3088 requires a second control signal applied to the SYNC input), set the LED short circuit threshold voltage (see the section “Setting the LED Short-Circuit Threshold” beginning on page 16), connect the LED strings and apply power (decoupled as instructed in the section “ ...
Page 13
... Because the boost regulator components are external useful for a number of topologies such as SEPIC, flyback, and single-switch forward converters. The boost regulator includes soft- start, adjustable cycle-by-cycle current limiting, and output over-voltage fault detection. Figure 8.1. Power section of MSL3086/MSL3088 1.1V SLOPE ...
Page 14
... The LED regulation current is set by a single resistor from ILED to GND. LED dimming is by PWM, and is controlled by default through an external signal(two signals in the case of the MSL3088), or optionally by internal registers accessed through the I interface (for interface information see the MSL3040/50/60/80/86/87/88/89 Programming Guide). LED drive dimming signals are phase shifted, where LED string on-times are successively delayed by 1/8th cycle from STR0 to STR7, reducing boost regulator transient response and increasing the transient frequency of the boost regulator ...
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... C serial interface allows control of PWM dimming, fault monitoring, and various other control functions. For a detailed explanation 2 of interface operation see the “MSL3040/50/60/80/86/87/88/89 Programming Guide”. C compatible serial interface. See the 2 Atmel MSL3086/MSL3088 Datasheet 8-String 60mA LED Drivers with Integrated Boost Controller and Phase Shifted Dimming 15 ...
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... R is queried at power up, and when EN is taken high, to set the threshold level. The MSL3088 does not have an SCTH SCTH input; the threshold is pre-set to 6.8V. Additionally, register 0x04 holds the Short Circuit Threshold level, changeable through the I C compatible serial interface ...
Page 17
... MOSFET switches and current sense resistors, allowing a wide variety of input/output voltage combinations and load currents. The boost regulator switching frequency is 625kHz. Switching frequencies of 350kHz, 500kHz, 750kHz, 875kHz and 1Mhz are also available; contact the factory for information. Atmel MSL3086/MSL3088 Datasheet 8-String 60mA LED Drivers with Integrated Boost Controller and Phase Shifted Dimming 17 ...
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... OOST EGULATOR Select the voltage divider resistors (R and R TOP every 1 second, and always increases the string volta OUT Atmel MSL3086/MSL3088 Datasheet O V UTPUT OLTAGE 8-String 60mA LED Drivers with Integrated Boost Controller and Phase Shifted Dimming and R in Figure 3 on page 13) by first determining V ...
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... V OUT V V OUT Atmel Inc., 2011. All rights reserved. is the output voltage and V OUT IN is the maximum (un-optimized) OUT is the maximum ( OUT Atmel MSL3086/MSL3088 Datasheet OUT and and V OUT(MIN) to ...
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... LED Drivers with Integrated Boost Controller and Phase Shifted Dimming is the top side voltage divider resistor (from the output voltage to FB), R TOP LOAD OUT , the right-half-plane zero f ESRZ , the right-half-plane zero f ESRZ Atmel MSL3086/MSL3088 Datasheet RH 20 COMP CO ...
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... F of the crossover frequency the crossover frequency the crossover frequency, or Atmel MSL3086/MSL3088 Datasheet R COMP C COM ...
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... The MSL3088 accepts two input signals, SYNC and PWM. SYNC provides the frequency information for the PWM dimming, and PWM provides the duty cycle information. The LED PWM dimming signals are staggered based on the frequency at SYNC. ...
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... Ordering Information Table 11.1 Ordering Information PART DESCRIPTION MSL3086-IU 8-CH LED driver with integrated boost controller and resistor based LED Short Circuit threshold setting. MSL3088-IU 8-CH LED driver with integrated boost and SYNC input. Atmel Corporation Atmel Asia Limited 2325 Orchard Parkway Unit 01-5 & 16, 19F ...