Tag Archives: Buck

How to control LM2596 buck-converter with microcontroller

by hugatry @ hackvlog.com:

Every now and then someone asks on different forums if there is an way to control cheap LM2596 modules with an Arduino or another microcontroller. I decided to demonstrate one solution that might be basic electronics for some, but still many don’t know about.

Those buck converters will change the output voltage to make the feedback pin, connected to the output via a voltage divider, become 1.25V or so. If feedback is higher, output gets lower and vice versa. If one changes the ratio of resistors in voltage divider, output voltage will change. This is usually done by turning a trimmer resistor with a screwdriver. That is good enough for many applications where voltage will be set only once, but sometimes there is a need to adjust the output voltage more frequently.

How to control LM2596 buck-converter with microcontroller – [Link]

Buck-boost regulator achieves high efficiency


by Susan Nordyk @ edn.com:

Using adaptive current-limit PFM (pulse frequency modulation) control, the ISL9120 switching regulator from Intersil realizes efficiencies of up to 98%, while automatically transitioning between buck and boost modes without significant output disturbance. The part accommodates a wide input voltage range of 1.8 V to 5.5 V and has an adjustable output voltage range of 1 V to 5.2 V for use with multiple power rails. It is capable of delivering up to 800 mA of output current (VIN = 2.5 V, VOUT = 3.3 V).

Buck-boost regulator achieves high efficiency – [Link]

Buck converter is pin-programmable


by Susan Nordyk @ edn.com:

Housed in a tiny 3×3-mm QFN package, the MIC24046-H synchronous step-down regulator from Micrel offers efficiency of greater than 90% peak and pin-selectable output voltage, switching frequency, and current limit. A wide input voltage range of 4.5 V to 19 V makes the part useful for distributed 12-V point-of-load applications.

The switching frequency of the MIC24046-H can be programmed to one of three options: 400 kHz, 565 kHz, or 790 kHz. Programmable output-voltage choices include 0.7 V, 0.8 V, 0.9 V, 1.0 V, 1.2 V, 1.5 V, 1.8 V, 2.5 V, and 3.3 V, while an internal divider is used to achieve ±1% voltage-output accuracy. The current limit of the regulator can be programmed to 3 A, 4 A, or 5 A.

Buck converter is pin-programmable – [Link]

A low-cost 0.5A 33V LED driver module with 90+% efficiency

LG-LED-150702-DF-Futuro Low-cost LED driver Design FigA

by Valentin Kulikov @ edn.com

This article describes simple constant current driver module with fast PWM input that can be used for driving medium and high power LEDs. The module uses an integrated constant-current output, DC-DC buck converter with output current configurable from 0.1 to 0.5A. This article outlines the schematic, design guidelines, operation, and performance of the low cost LED driver.

A low-cost 0.5A 33V LED driver module with 90+% efficiency – [Link]

600 mA Constant On-Time Buck Regulator


The LM5017 is a 600 mA constant on-time synchronous buck regulator with built-in high side and low side MOSFETs. This device has a wide input voltage range from 7. 5 V to 100 V. The constant on-time control scheme used in this device doesn’t need loop compensation, delivers excellent transient response, and enables very high step-down ratios. The on-time varies inversely with the input voltage resulting in nearly constant frequency over the input voltage range. A high voltage startup regulator provides bias power for internal operation of the IC and for integrated gate drivers.

600 mA Constant On-Time Buck Regulator – [Link]

Buck Converter (DC-DC)


by xKOBAYASHIMARUx @ instructables.com:

Buck Converters are great! I use them all over the place in many of my nerdy, techy, geeky hobbiest projects. They also can commonly be referred to by other names, a DC-DC converter or a switching regulator. Essentially what it does is take some higher voltage in (higher than what you want for your project), chops it up, and pieces together a lower voltage. It might help to think of it as a transformer for DC circuits… only without the giant iron block… and without the long coils of wire… and with only 3 pins.

Buck Converter (DC-DC) – [Link]

High Voltage Buck-Boost Regulator


The LTM8056 from Linear Technology is a 58 VIN, buck-boost μModule® (micromodule) regulator which requires just a few external passive components to complete the regulator design. Included in the package are the switching controller, power switches, inductor and support components. The basic external components needed are a single resistor to set the switching frequency, a resistor divider network to set the output voltage together with input and output capacitors. Other features such as input and output average current regulation may be implemented with just a few additional components. The LTM8056 operates with an input voltage ranging from 5 V to 58 V and can supply a regulated output voltage between 1.2 V and 48 V. The SYNC input and CLKOUT signal output provide clock synchronization options.

High Voltage Buck-Boost Regulator – [Link]

Buck controller needs just 29 µA in standby


The LTC®3892/LTC3892-1 is a high performance dual step-down DC/DC switching regulator controller that drives all N-channel synchronous power MOSFET stages. Power loss and noise are minimized by operating the two controller output stages out-of-phase.

The gate drive voltage can be programmed from 5V to 10V to allow the use of logic or standard-level FETs and to maximize efficiency. Internal switches in the top gate drivers eliminate the need for external bootstrap diodes.

A wide 4.5V to 60V input supply range encompasses a wide range of intermediate bus voltages and battery chemistries. Output voltages up to 99% of VIN can be regulated. OPTILOOP ® compensation allows the transient response and loop stability to be optimized over a wide range of output capacitance and ESR values.

Buck controller needs just 29 µA in standby – [Link]

Buck converter starts up in just 70 ms


by Susan Nordyk @ edn.com:

The LTC3887 dual-output synchronous step-down DC/DC converter from Linear Technology differs from its predecessor, the LTC3880, by offering an enhanced feature set that includes a faster 70-ms power-up time, higher output voltage, and a speedy ADC mode that provides an 8-ms update rate for one parameter. Housed in a 40-pin, 6×6-mm QFN package, the LTC3887 occupies the same board footprint as the previous version and operates over a temperature range of -40 C to +125 C.

Gate drivers integrated within the LTC3887 drive all N-channel MOSFETs from input voltages of 4.5 V to 24 V. The converter can regulate two independent outputs or can be configured for a two-phase single output. Up to six phases can be interleaved and paralleled for accurate sharing among multiple ICs, minimizing input and output filtering requirements for high current and/or multiple-output applications. The LTC3887 provides output voltages from 0.5 V to 5.5 V, accurate to within +/-0.5%, with output currents of up to 30 A per phase over the full operating temperature range.

Buck converter starts up in just 70 ms – [Link]

High-voltage buck regulators stay cool in tiny packages


by Susan Nordyk @ edn.com:

A family of pin-compatible synchronous step-down switching regulators with integrated power switches, the MIC28511/12/13 from Micrel, supplies up to 4 A of output current (MIC28513) and accepts a wide input supply range of 4.6 V to 70 V (MIC28512). The devices have an operating junction temperature range of -40°C to +125°C and come in very small 24-pin, 3×4-mm FCQFN packages.

The MIC28511/12/13 regulators are offered in both Hyper Speed Control and HyperLight Load architectures, which allow for high VIN (low VOUT) operation and fast transient response, while reducing the required output capacitance and providing good light-load efficiency. They furnish an adjustable output voltage as low as 0.8 V with guaranteed accuracy to within ±1%.

High-voltage buck regulators stay cool in tiny packages – [Link]