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Wide Input Range, 3.3V SEPIC Converter Can Operate from 3V to 36V ("Cold Crank")

While requiring 6V to start up, the addition of a diode tied from output to input allows this circuit to operate as the battery sags all the way down to 3V. This wide input voltage range is required for automotive cold crank applications.

The LT3581 is a PWM DC/DC converter with built-in fault protection features to aid in protecting against output shorts, input/output overvoltages, and overtemperature conditions. The part consists of a 42V master switch, and a 42V slave switch that can be tied together for a total current limit of 3.3A.

28VIN /0V to 28V SEPIC SuperCap Charger with Input Current Limit

The LT3956 is a DC/DC converter designed to operate as a constant-current source and constant-voltage regulator. It is ideally suited for driving high current LEDs. It features an internal low side N-channel power MOSFET rated for 84V at 3.3A and driven from an internal regulated 7.15V supply. The fixed frequency, current-mode architecture results in stable operation over a wide range of supply and output voltages. A ground referenced voltage FB pin serves as the input for several LED protection features, and also makes it possible for the converter to operate as a constant-voltage source. A frequency adjust pin allows the user to program the frequency from 100kHz to 1MHz to optimize efficiency, performance or external component size.

12V Power Ride Through

The LTC3625/LTC3625-1 are programmable supercapacitor chargers designed to charge two supercapacitors in series to a fixed output voltage (4.8V/5.3V or 4V/4.5V selectable) from a 2.7V to 5.5V input supply. Automatic cell balancing prevents overvoltage damage to either supercapacitor while maximizing charge rate. No balancing resistors are required.

5V Power Ride Through

The LTC3625/LTC3625-1 are programmable supercapacitor chargers designed to charge two supercapacitors in series to a fixed output voltage (4.8V/5.3V or 4V/4.5V selectable) from a 2.7V to 5.5V input supply. Automatic cell balancing prevents overvoltage damage to either supercapacitor while maximizing charge rate. No balancing resistors are required.

Solar Powered Super Capacitor Charger with MPPT

The LTC3625/LTC3625-1 are programmable supercapacitor chargers designed to charge two supercapacitors in series to a fixed output voltage (4.8V/5.3V or 4V/4.5V selectable) from a 2.7V to 5.5V input supply. Automatic cell balancing prevents overvoltage damage to either supercapacitor while maximizing charge rate. No balancing resistors are required.

Piezoelectric Energy Harvester and 1.2V Secondary Rail

The LTC3388-1/LTC3388-3 are high efficiency step-down DC/DC converters with internal high side and synchronous power switches that draw only 720nA typical DC supply current at no load while maintaining output voltage regulation.The EN pin can be used to activate the LTC3388-1/LTC3388-3.

For instance, in this circuit the LTC3388-1 is enabled by the PGOOD output of the LTC3588-1, a piezoelectric energy harvesting power supply, to create a 1.2V rail. The quiescent current that the LTC3388-1 draws will appear at the input of the LTC3588-1, reduced by the conversion ratio of the LTC3588-1 buck converter. Because the LTC3388-1 is driven by a 3.3V supply no capacitors are needed for the internal VIN2 and CAP rails.

Automotive 9V - 19.5Vin to 5V at 1A with 60V Transient Protection and 1.7MHz Switching Frequency

The LT3682 is a 1A monolithic buck switching regulator that accepts input voltages from 3.6V to 36V and transients up to 60V. It features an adjustable and synchronizable switching frequency from 250kHz to 2.2MHz. It also has the ability to monitor the current flowing through the external catch diode, thus providing an extra level of protection against output fault conditions over the entire operating frequency range, regardless of input voltage. These features, together with its typical 75μA no load quiescent current makes the LT3682 the right choice in high frequency automotive and battery powered applications.

High Efficiency Wide Input ("Cold Crank") Range Dual 5V/8.5V Converter

The LTC3859 is a high performance triple output (buck/ buck/boost) synchronous DC/DC switching regulator controller that drives all N-channel power MOSFET stages. Constant frequency current mode architecture allows a phase-lockable switching frequency of up to 850kHz. The LTC3859 operates from a wide 4.5V to 38V input supply range. When biased from the output of the boost converter or another auxiliary supply, the LTC3859 can operate from an input supply as low as 2.5V after start-up.

4V to 18V ("Cold Crank") Input to 12V Output 3mm Maximum Height All Ceramic SEPIC

12V buses are often derived from sources with a wide input voltage range. For instance, automotive solutions can have steady-state operating voltages as high as 18V and as low as 4V for cold-crank conditions. Figure 4 shows a simple, low cost and low profile (3mm) solution that avoids the high cost of using both a boost and buck converter and maintains 12V system power during cold crank conditions.

4V-60V ("Cold Crank") Input to 5V Output DC/DC Automotive Converter

Ultrawide input voltage requirements are a common design problem for DC/DC converter applications, but when that range includes voltages both above and below the output voltage, the converter must perform both step-up and step-down functions. The LT3433 is a high voltage monolithic DC/DC converter that incorporates two switch elements, allowing for a unique topology that accommodates both step-up and step-down conversion using a single inductor.

A 4V-60V to 5V DC/DC converter is shown in Figure 2. This converter is well suited for 12V automotive battery applications, maintaining output voltage regulation with battery line voltages from 4V cold crank through 60V load dump.

30W White LED Headlamp Driver with Thermal Derating

The LT3756, LT3756-1 and LT3756-2 are DC/DC controllers designed to operate as a constant-current source for driving high current LEDs. They drive a low side external N-channel power MOSFET from an internal regulated 7.15V supply. The fixed frequency, current-mode architecture results in stable operation over a wide range of supply and output voltages. A ground referenced voltage FB pin serves as the input for several LED protection features, and also makes it possible for the converter to operate as a constant-voltage source. A frequency adjust pin allows the user to program the frequency from 100kHz to 1MHz to optimize efficiency, performance or external component size.

94% Efficient 25W White LED Headlamp Driver

The LT3956 is a DC/DC converter designed to operate as a constant-current source and constant-voltage regulator. It is ideally suited for driving high current LEDs. It features an internal low side N-channel power MOSFET rated for 84V at 3.3A and driven from an internal regulated 7.15V supply. The fixed frequency, current-mode architecture results in stable operation over a wide range of supply and output voltages. A ground referenced voltage FB pin serves as the input for several LED protection features, and also makes it possible for the converter to operate as a constant-voltage source. A frequency adjust pin allows the user to program the frequency from 100kHz to 1MHz to optimize efficiency, performance or external component size.

50W White LED Headlamp Driver

The LT3755, LT3755-1 and LT3755-2 are DC/DC controllers designed to operate as a constant-current source for driving high current LEDs. They drive a low side external N-channel power MOSFET from an internal regulated 7.15V supply. The fixed frequency, current mode architecture results in stable operation over a wide range of supply and output voltages. A ground referenced voltage FB pin serves as the input for several LED protection features, and also makes it possible for the converter to operate as a constant-voltage source. A frequency adjust pin allows the user to program the frequency from 100kHz to 1MHz to optimize efficiency, performance or external component size.

Single 2.7V Supply 4MHz 4th Order Butterworth Filter

Benefitting from low voltage operation and rail-to-rail output, a low power filter that is suitable for antialiasing can be built as shown in this circuit. On a 2.7V supply the filter has a passband of approximately 4MHz with 2VP-P input signal and a stopband attenuation that is greater than
–75dB at 43MHz. The resistor and capacitor values can be scaled to reduce noise at the cost of large signal power consumption and distortion.

The LTC6246/LTC6247/LTC6248 are single/dual/quad low
power, high speed unity gain stable rail-to-rail input/output operational amplifiers. On only 1mA of supply current they feature an impressive 180MHz gain-bandwidth product, 90V/μs slew rate and a low 4.2nV/√Hz of input referred.
noise.

1.8V, 140μA, 100kHz, Lowpass Filter (Single-Ended Input and Differential Output)

The LTC6256 circuit shown here is a 2nd order, 100kHz, Butterworth lowpass filter. The filter’s differential
output maximizes the dynamic range in very low voltage
operation.

The LTC6255/LTC6256/LTC6257 are single/dual/quad operational amplifiers with low noise, low power, low supply voltage, rail-to-rail input/output. They are unity gain stable with capacitive load up to 100nF. They feature 6.5MHz gain-bandwidth product, 1.8V/μs slew rate while consuming only 65μA of supply current per amplifier operating on supply voltages ranging from 1.8V to 5.25V