LM3429BSTEVAL National Semiconductor, LM3429BSTEVAL Datasheet
LM3429BSTEVAL
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LM3429BSTEVAL Summary of contents
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... The LM3429 comes in a low profile, thermally efficient TSSOP EP 14-lead package. The LM3429Q1 is an Automotive Grade product that is AEC- Q100 grade 1 qualified Typical Boost Application Circuit © 2010 National Semiconductor Corporation LM3429 LM3429Q1 Features ■ LM3429Q1 is an Automotive Grade product that is AEC- Q100 grade 1 qualified (-40° ...
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Connection Diagram Ordering Information Order Number Spec. Package Type LM3429MH NOPB TSSOP-14 EP LM3429MHX NOPB TSSOP-14 EP LM3429Q1MH NOPB TSSOP-14 EP LM3429Q1MHX NOPB TSSOP-14 EP *Automotive Grade (Q) product incorporates enhanced manufacturing and support processes for the automotive market, including ...
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... Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications nDIM IN OVP, HSP, HSN RCT - continuous COMP, CSH GATE - continuous Electrical Characteristics Specifications in standard type face are for T Range ( T = −40°C to +125°C). Minimum and Maximum limits are guaranteed through test, design, or statistical correlation. Typical ...
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Symbol Parameter PWM COMPARATOR COMP to PWM Offset CURRENT LIMIT (IS) V Current Limit Threshold LIM V Delay to Output LIM t Leading Edge Blanking ON-MIN Time HIGH SIDE TRANSCONDUCTANCE AMPLIFIER Input Bias Current Transconductance Input Offset Current Input Offset ...
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Typical Performance Characteristics Boost Efficiency vs. Input Voltage V = 32V (9 LEDs) (Note O Boost LED Current vs. Input Voltage (Note V = 32V (9 LEDs) O Analog Dimming (Note V = 20V (6 LEDs =+25°C and ...
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V vs. Junction Temperature CSH V vs. Junction Temperature RCT t vs. Junction Temperature ON-MIN www.national.com V vs. Junction Temperature CC 300944b0 V vs. Junction Temperature LIM 300944b2 300944b4 6 300944b1 300944b3 ...
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Block Diagram Theory of Operation The LM3429 is an N-channel MosFET (NFET) controller for buck, boost and buck-boost current regulators which are ideal for driving LED loads. The controller has wide input voltage range allowing for regulation of a variety ...
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The average output LED current (I LED average inductor current ( therefore trolled, I will be well regulated. As the system changes LED input voltage or output voltage, the ideal duty cycle (D) is var- ...
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Adding a PNP transistor as shown in constant ripple over varying FIGURE 3. Off-timer Circuitry for Buck Regulators The switching frequency is defined: Buck (Constant Ripple vs Buck (Constant Ripple vs ...
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ANALOG DIMMING The CSH pin can be used to analog dim the LED current by adjusting the current sense voltage (V different methods to adjust V using the CSH pin: SNS 1. External variable resistance : Adjust a potentiometer placed ...
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CONTROL LOOP COMPENSATION The LM3429 control loop is modeled like any current mode controller. Using a first order approximation, the uncompen- sated loop can be modeled as a single pole created by the output capacitor and, in the boost and ...
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To mitigate this problem, a compensator should be designed to give adequate phase margin (above 45°) at the crossover frequency. A simple compensator using a single capacitor at the COMP pin (C ) will add a dominant pole to the ...
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INPUT UNDER-VOLTAGE LOCKOUT (UVLO) The nDIM pin is a dual-function input that features an accurate 1.24V threshold with programmable hysteresis as shown in Figure 12. This pin functions as both the PWM dimming input for the LEDs and as a ...
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Design Considerations This section describes the application level considerations when designing with the LM3429. For corresponding calcu- lations, refer to the Design Guide section. INDUCTOR The inductor (L1) is the main energy storage device in a switching regulator. Depending on ...
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N-CHANNEL MosFET (NFET) The LM3429 requires an external NFET (Q1) as the main power MosFET for the switching regulator recommend have a voltage rating at least 15% higher than the maximum transistor voltage to ensure safe ...
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Basic Topology Schematics BOOST REGULATOR (V < BUCK REGULATOR (V > www.national.com 16 30094422 30094451 ...
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BUCK-BOOST REGULATOR 17 30094450 www.national.com ...
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Design Guide Refer to Basic Topology Schematics section. SPECIFICATIONS Number of series LEDs: N Single LED forward voltage: V LED Single LED dynamic resistance: r LED Nominal input voltage Input voltage range IN-MAX IN-MIN Switching ...
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LED RIPPLE CURRENT Set the nominal LED ripple current (Δi LED-PP the output capacitance ( Buck Boost and Buck-boost To set the worst case LED ripple current, use D solving for The minimum allowable ...
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A high frequency compensation pole (ω attenuate switching noise and provide better gain margin. As- = 10Ω, C suming R is calculated according to the higher FS FS value of the pole and the RHP zero of the system (shown ...
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The current rating should be at least 10% higher than the maximum average diode current (I D-MAX Buck Boost and Buck-boost Replace D with D in the I equation to solve for the MAX D-MAX average diode current (I ). ...
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Design Example #1 BUCK-BOOST APPLICATION - 6 LEDs at 1A SPECIFICATIONS 3.5V LED r = 325 mΩ LED V = 24V 10V IN-MIN V = 70V IN-MAX f = 700 kHz SW ...
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AVERAGE LED CURRENT Solve for R : SNS Assume R = 12.4 kΩ and solve for R CSH The closest standard resistor for R is actually 0.1Ω and for SNS R is actually 1 kΩ therefore I is: HSP ...
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T is approximated ensure stability, calculate ω Solve for C : CMP To attenuate switching noise, calculate ω = 10Ω and solve for C Assume The chosen components from step 7 are: 8. ...
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The closest standard resistor is 21 kΩ making V The chosen components from step 11 are: 12. OUTPUT OVLO Solve for R : OV2 Design #1 Bill of Materials Qty Part ID 1 LM3429 1 C CMP ...
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Applications Information DESIGN #2: BOOST PWM DIMMING APPLICATION - 9 LEDs at 1A Design #2 Bill of Materials Qty Part ID 1 LM3429 CMP ...
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DESIGN #3: BUCK-BOOST ANALOG DIMMING APPLICATION - 4 LEDs at 2A Design #3 Bill of Materials Qty Part ID 1 LM3429 1 C CMP ...
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DESIGN #4: BOOST ANALOG DIMMING APPLICATION - 12 LEDs at 700mA Design #4 Bill of Materials Qty Part ID 1 LM3429 1 C CMP ...
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DESIGN #5: BUCK-BOOST PWM DIMMING APPLICATION - 6 LEDs at 500mA Design #5 Bill of Materials Qty Part ID 1 LM3429 1 C CMP ...
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DESIGN #6: BUCK APPLICATION - 3 LEDS AT 1.25A Design #6 Bill of Materials Qty Part ID 1 LM3429 1 C CMP ...
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DESIGN #7: BUCK-BOOST THERMAL FOLDBACK APPLICATION - 8 LEDs at 2.5A Design #7 Bill of Materials Qty Part ID 1 LM3429 1 C CMP ...
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DESIGN #8: SEPIC APPLICATION - 5 LEDs at 750mA Design #8 Bill of Materials Qty Part ID 1 LM3429 1 C CMP ...
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Physical Dimensions inches (millimeters) unless otherwise noted For Ordering, Refer to Ordering Information Table TSSOP-14 Pin EP Package (MXA) NS Package Number MXA14A 33 www.national.com ...
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