LT3430EFE#TRPBF Linear Technology, LT3430EFE#TRPBF Datasheet
LT3430EFE#TRPBF
Specifications of LT3430EFE#TRPBF
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LT3430EFE#TRPBF Summary of contents
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... SYNC pin can be externally synchronized with a logic level input from 228kHz to 700kHz for the LT3430 or from 125kHz to 250kHz for the LT3430-1. The LT3430/LT3430-1 are available in a thermally enhanced 16-pin TSSOP package. , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. *US Patent # 6498466 MMSD914TI 0.68µF 22µH ...
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LT3430/LT3430-1 ABSOLUTE MAXIMUM RATINGS (Note 1) Input Voltage (V ) .................................................. 60V IN BOOST Pin Above SW (Note 11) .............................. 35V BOOST Pin Voltage ................................................. 68V SYNC Voltage ............................................................. 7V ⎯ S ⎯ H ⎯ D ⎯ N Voltage ............................................................ ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are Open Circuit, unless otherwise noted. PARAMETER Maximum Switch Duty Cycle (LT3430-1) Switch Frequency (LT3430) Switch Frequency (LT3430-1) f Line Regulation SW f Shifting Threshold SW Minimum Input Voltage ...
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LT3430/LT3430-1 TYPICAL PERFORMANCE CHARACTERISTICS Switch Peak Current Limit 25° TYPICAL 4 GUARANTEED MINIMUM DUTY CYCLE (%) 3430 G01 Lockout and Shutdown Threshold 2.4 LOCKOUT 2.0 1.6 1.2 0.8 ...
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TYPICAL PERFORMANCE CHARACTERISTICS Switching Frequency 230 (LT3430) 220 210 200 190 180 170 –50 – 100 JUNCTION TEMPERATURE (°C) 3430 G10 V Pin Shutdown Threshold C 2.1 1.9 1.7 1.5 1.3 1.1 0.9 0.7 –50 –25 ...
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LT3430/LT3430-1 PIN FUNCTIONS GND (Pins 16, 17): The GND pin connections act as the reference for the regulated output, so load regulation will suffer if the “ground” end of the load is not at the same voltage ...
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BLOCK DIAGRAM The LT3430/LT3430-1 are constant frequency, current mode buck converters. This means that there is an in- ternal clock and two feedback loops that control the duty cycle of the power switch. In addition to the normal error amplifi ...
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LT3430/LT3430-1 APPLICATIONS INFORMATION FEEDBACK PIN FUNCTIONS The feedback (FB) pin on the LT3430/LT3430-1 is used to set output voltage and provide several overload protection features. The fi rst part of this section deals with selecting resistors to set output voltage ...
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APPLICATIONS INFORMATION LT3430 AMPLIFIER Q2 V GND C tion should be used if resistors are increased beyond the suggested values and short-circuit conditions occur with high input voltage. High frequency pickup will increase and the protection accorded by frequency and ...
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LT3430/LT3430-1 APPLICATIONS INFORMATION inductor value to achieve a desirable output ripple volt- age level. If output ripple voltage is of less importance, the subsequent suggestions in Peak Inductor and Fault Current and EMI will additionally help in the selection of ...
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... After making an initial choice, consider additional factors such as core losses and second sourcing, etc. Use the experts in Linear Technology’s Applications department if you feel uncertain about the fi nal choice. They have ex- perience with a wide range of inductor types and can tell you about the latest developments in low profi ...
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LT3430/LT3430-1 APPLICATIONS INFORMATION Reduced Inductor Value and Discontinuous Mode If the smallest inductor value is of most importance to a converter design, in order to reduce inductor size/cost, discontinuous mode may yield the smallest inductor solu- tion. The maximum output ...
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APPLICATIONS INFORMATION where switching frequency t = switch minimum on time diode forward voltage Input voltage IN I • inductor I • R voltage drop If this condition is not ...
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LT3430/LT3430-1 APPLICATIONS INFORMATION frequency gain of the error amplifi er, including the gain at the switching frequency. If the gain of the error amplifi high enough at the switching frequency, output ripple voltage (although smaller for a ceramic ...
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APPLICATIONS INFORMATION poor RFI behavior and if the overshoot is severe enough, damage the IC itself. The suggested catch diode (D1 International Recti- fi er 30BQ060 Schottky rated at 3A average forward current and 60V reverse ...
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LT3430/LT3430-1 APPLICATIONS INFORMATION INPUT − ∆ OUT = − µ ...
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APPLICATIONS INFORMATION LAYOUT CONSIDERATIONS As with all high frequency switchers, when considering layout, care must be taken in order to achieve optimal electrical, thermal and noise performance. For maximum effi ciency, switch rise and fall times are typically in the ...
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LT3430/LT3430-1 APPLICATIONS INFORMATION The V and FB components should be kept as far away as C possible from the switch and boost nodes. The LT3430/ LT3430-1 pinout has been designed to aid in this. The ground for these components should ...
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APPLICATIONS INFORMATION THERMAL CALCULATIONS Power dissipation in the LT3430/LT3430-1 chip comes from four sources: switch DC loss, switch AC loss, boost circuit current, and input quiescent current. The follow- ing formulas show how to calculate each of these losses. These ...
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LT3430/LT3430-1 APPLICATIONS INFORMATION lower V may generate greater losses due to switch DC IN losses. In general, the maximum and minimum V should be checked with maximum typical load current for calculation of the LT3430/LT3430-1 die temperature more ...
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APPLICATIONS INFORMATION ings = 0.233W • 45°C/W = 11°C. The 7V zener should be sized for excess of 0.233W operaton. The tolerances of the zener should be considered to ensure minimum V exceeds 3. DROOP Input Voltage ...
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LT3430/LT3430-1 APPLICATIONS INFORMATION stability. This ESR, however, contributes signifi cantly to the ripple voltage at the output (see Output Ripple Voltage in the Applications Information section possible to reduce capacitor size and output ripple voltage by replac- ing ...
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APPLICATIONS INFORMATION LT3430/LT3430-1 will consume their quiescent operating current of 1.5mA. The V pin will also source current to IN any other components connected to the input line. If this load is greater than 10mA or the input could be ...
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LT3430/LT3430-1 APPLICATIONS INFORMATION DUAL OUTPUT SEPIC CONVERTER The circuit in Figure 14 generates both positive and negative 5V outputs with a single piece of magnetics. The two induc- tors shown are actually just two windings on a standard Coiltronics inductor. ...
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APPLICATIONS INFORMATION D2 MMSD914TI C2 0.68µF INPUT BOOST 5. 44V LT3430 FB GND 4.7µF 30BQ060 100V C C CER INCREASE L1 FOR HIGHER CURRENT APPLICATIONS. SEE ...
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LT3430/LT3430-1 APPLICATIONS INFORMATION value equal to the peak-to-peak triangular waveform of the inductor. The low output ripple design in Figure 15 places the input capacitor between V and the regulated negative IN output. This placement of the input capacitor signifi ...
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... DIMENSIONS ARE IN 3. DRAWING NOT TO SCALE Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. FE Package 16-Lead Plastic TSSOP (4 ...
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... High Effi ciency OUT Step-Up Step-Down DC/DC Converter with Burst Mode Operation LTC3727/LTC3727-1 36V, 500kHz, High Effi ciency Step-Down DC/DC Controllers Burst Mode is a registered trademark of Linear Technology Corporation. Linear Technology Corporation 28 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● ...