LM3532TMX-40ANOPB National Semiconductor Corporation, LM3532TMX-40ANOPB Datasheet
LM3532TMX-40ANOPB
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LM3532TMX-40ANOPB Summary of contents
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... The LM3532 is available in a 16-bump, 0.4mm pitch thin micro SMD (1.745 mm x 1.845 mm x 0.6 mm). The device operates over a 2.7V to 5.5V input voltage range and the −40°C to +85° C temperature range. Typical Application Circuit © 2011 National Semiconductor Corporation LM3532 Features ■ Drives Parallel High-Voltage LED Strings at 40V each with up to 90% efficiency ■ ...
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... GRM21BR71H105KA12L CIN Murata GRM188R71A225KE15D Connection Diagram Ordering Information Order Number Package Type LM3532TME-40A NOPB 16-Bump micro SMD 250 units, Tape-and- LM3532TMX-40A NOPB 16-Bump micro SMD 3000 units, Tape-and- www.national.com Package Value Designator TMD16FKA 1.745 mm x 1.845 µ 1.7 mm 1µ ...
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Pin Descriptions/Functions Pin Name Description Output Voltage Sense Connection for Over Voltage Sensing. Connect OVP to the positive A1 OVP terminal of the output capacitor. Input Terminal to High Voltage Current Sink #3 (40V max). The boost converter regulates the ...
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Absolute Maximum Ratings 2) If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications GND OVP ILED1 ILED2 ILED3 ...
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Symbol Parameter V Output Logic Low (SCL, INT) OL PWM Input Internal Pulldown R PWM Resistance (PWM1, PWM2 C-COMPATIBLE TIMING SPECIFICATIONS (SCL, SDA, see ) t SCL (Clock Period Data In Setup Time to SCL High ...
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Note 1: Absolute Maximum Ratings are limits beyond which damage to the device may occur. Operating Ratings are conditions for which the device is intended to be functional, but device parameter specifications may not be guaranteed. For guaranteed specifications and ...
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Typical Performance Characteristics C = 2.2 µ Coilcraft LPS4018 (10 µ µH Efficiency vs V Single String, ILED = 20.2mA L = LPS4018-103ML (10µH) Efficiency vs V Dual String, ILED = 20.2mA per string ...
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Efficiency vs V Single String, ILED = 20.2mA per string L = LPS4018-223ML (22µH) Efficiency vs V Dual String, ILED = 20.2mA per string L = LPS4018-223ML (22µH) Efficiency vs V Triple String, ILED = 20.2mA per string L = ...
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Efficiency vs I LED Triple String, VIN = 3. LPS4018-103ML (10µH) 30115463 Efficiency vs I LED Triple String, VIN = 3. LPS4018-223ML (22µH) 30115465 Shutdown Current vs VIN HWEN = GND 30115479 Efficiency vs I LED ...
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Current Sink Matching vs VIN ILED1 to ILED2 to ILED3 (ΔILED is worst case difference between all three strings) ALS Resistor Matching vs VIN (2.44kΩ setting) Differential Non Linearity vs Code www.national.com ALS Resistance vs VIN R ALS1 30115482 Integral ...
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LED Current vs Headroom Voltage 30115473 11 www.national.com ...
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Operational Description 40V BOOST CONVERTER The LM3532 contains a 40V maximum output voltage, asyn- chronous boost converter with an integrated 250 mΩ switch and three low-side current sinks. Each low-side current sink is independently programmable from mA. ...
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LM3532 CURRENT SINK CONFIGURATION Control of the LM3532’s three current sinks is done by con- figuring the three internal control banks (Control A, Control B, and Control C) (see Figure 2). Any of the current sinks (ILED1, FIGURE 2. LM3532 ...
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LED CURRENT RAMPING The LM3532 provides 4 methods to control the rate of rise or fall of the LED current during these events: 1. Startup from 0 to the initial target 2. Shutdown 3. Ramp up from one brightness level ...
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LINEAR CURRENT MAPPING In linear mapping mode the backlight code to LED current approximates the following equation: LED CURRENT CONTROL Once the Full-Scale Current is set, control of the LM3532’s LED current can be done via 2 methods ...
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TABLE 1. I Current Sink Brightness Register Assignment Output Configuration Control A Brightness Register Configuration Bits[1:0] = 00, assigns Register Bits [4:2] ILED1 to Control Bank A 000 selects Control A Bits[3: assigns Zone Target 0 as ILED2 ...
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FIGURE 5. Ambient Light Input to Backlight Mapping AMBIENT LIGHT ZONE HYSTERESIS For each Zone Boundary there are two Zone Boundary Reg- isters: a Zone Boundary High Register and a Zone Boundary Low Register. The difference between the Zone Boundary ...
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PWM ENABLED FOR A PARTICULAR ZONE The active PWM input for a specified Control Bank can be enabled/disabled for each ALS Brightness Zone. This is done via bits[6:2] of the corresponding Control PWM Registers (see Table ...
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ALS AVERAGING ALS averaging is used to filter out any fast changes in the ambient light sensor inputs. This prevents the backlight cur- rent from constantly changing due to rapid fluctuations in the ambient light. There are 8 separate averaging ...
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DIRECT ALS CONTROL In direct ALS control the LM3532’s ALS Interface can force the backlight current to either a higher zone target or a lower zone target using the rules described in the ALS Rules sec- tion. In the example ...
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DOWN DELAY The Down-Delay algorithm uses all the same rules from the ALS Rules section, except it provides for adding additional average period delays required for decreasing transitions of the Averager Output, before the LED current is programmed to a ...
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Zone 4 to Zone result the backlight current is programmed to Zone 2's target current. www.national.com FIGURE 11. ALS Down-Delay Control 22 30115409 ...
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INTERRUPT OUTPUT INT is an open drain output that pulls low when the ALS is enabled and when one of the ALS inputs transitions into a new zone. At the same time, the ALS Zone Information register is updated with ...
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Output Voltage Limited When the LM3532's output voltage (highest voltage LED string + 400 mV headroom voltage) reaches 40V, the OVP threshold is hit, and the NFET turns off and remains off until the output voltage drops 1V below the ...
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I 2 C-Compatible Interface START AND STOP CONDITION The LM3532 is controlled via C-compatible interface. START and STOP conditions classify the beginning and the end of the session. A START condition is defined as ...
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LM3532 Register Descriptions Name Address Output Configuration Startup/Shutdown Ramp Rate Run Time Ramp Rate Control A PWM Control B PWM Control C PWM Control A Brightness Control A Full-Scale Current Control B Brightness Control B Full-Scale Current ...
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OUTPUT CONFIGURATION This register configures how the three control banks are rout the current sinks (ILED1, ILED2, ILED3) TABLE 3. Output Configuration Register Description (Address 0x10) Bits [5:4] Bit [7:6] ILED3 Control Not Used 00 = ILED3 is ...
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CONTROL A PWM This register configures which PWM input (PWM1 or PWM2) is mapped to Control Bank A and which zones the selected PWM input is active in. TABLE 6. Control A PWM Register Description (Address 0x13) Bit 7 Bit ...
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CONTROL A BRIGHTNESS CONFIGURATION The Control A Brightness Configuration Register has 3 func- tions: 1. Selects how the LED current sink which is mapped to Control Bank A is controlled (either directly through the via the ...
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CONTROL A/B/C FULL-SCALE CURRENT These registers program the full-scale current setting for the current sink(s) assigned to Control Bank A/B/C. Each Control TABLE 12. Control A/B/C Full-Scale Current Registers Descriptions (Address 0x17, 0x19, 0x1B) Bits [7:5] Not Used N/A www.national.com ...
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FEEDBACK ENABLE The Feedback Enable Register configures which current sinks are or are not part of the boost control loop. TABLE 13. Feedback Enable Register Description (Address 0x1C) Bits [7:3] Not Used N/A CONTROL ENABLE The Control Enable register contains ...
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ALS1 & 2 RESISTOR SELECT The ALS Resistor Select Registers program the internal pull- down resistor at the ALS1/ALS2 input. Each ALS input has its own resistor select register (ALS1 Resistor Select Register, Address 0x20) and (ALS2 Resistor Select Register, ...
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ALS DOWN DELAY The ALS Down Delay Register adds additional average time delays for ALS changes in the backlight current during falling TABLE 16. ALS Down Delay Register Description (Address 0x22) Bits [7:6] Not Used 0 = ALS Fast startup ...
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ALS ZONE READBACK / INFORMATION The ALS Zone Readback and ALS Zone Information Read- back registers each contain information on the current ambi- ent light brightness zone. The ALS Zone Readback register contains the ALS Zone after the averager and ...
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ALS ZONE BOUNDARIES There are 4 ALS Zone Boundary registers which form the boundaries for the 5 Ambient Light Zones. Each Zone Bound- ary register is 8 bits with a maximum voltage of 2V. This gives a step size for ...
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Applications Information INDUCTOR SELECTION The LM3532 is designed to work with a 10 µ µH in- ductor. When selecting the inductor, ensure that the satura- tion rating is high enough to accommodate the applications peak inductor current . ...
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DIODE SELECTION The diode connected between SW and OUT must be a Schot- tky diode and have a reverse breakdown voltage high enough to handle the maximum output voltage in the application. ble 22 lists various diodes that can be ...
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LAYOUT GUIDELINES The LM3532 contains an inductive boost converter which sees a high switched voltage (up to 40V) at the SW pin, and a step current (up to 1A) through the Schottky diode and out- put capacitor each switching cycle. ...
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Output Capacitor Placement The output capacitor is in the path of the inductor current dis- charge current result, C sees a high current step OUT from each time the switch turns off and the Schottky ...
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FIGURE 17. Input RLC Network 40 301154102 ...
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Example Layouts The following figures show example layouts which apply the required (proper) layout guidelines. These figures should be used as guides for laying out the LM3532's boost circuit. 30115485 FIGURE 18. Layout Example #1 FIGURE 19. Layout Example #2 ...
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Physical Dimensions X1 = 1.745 mm (±0.1 mm 1.845 mm (±0.1 mm 0.600 mm www.national.com inches (millimeters) unless otherwise noted 16-Bump Thin Micro SMD Package For Ordering, Refer to Ordering Information Table NS Package Number TMD16 ...
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Notes 43 www.national.com ...
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