Buck Converters

A Buck Converter, also known as a Step-Down Converter, is a DC-to-DC power converter that steps down the voltage from its input to its output. A buck converter integrates the core components and circuitry needed into a single device.

Buck converters are found in countless electronic applications, where their power regulation properties are a vital component.

How does a Buck Converter work?

A Buck Converter is a type of switch-mode power supply, a class of device that incorporates a switch (e.g. typically a MOSFET) to rapidly turn the circuit on and off. This rapid switching creates a square wave. If the duty cycle of the switch is set to 50%, i.e. the switch is on 50% of the time, the average voltage will be 50% of the input.

The square wave needs to be smoothed to provide useful power, typically an inductor and capacitor are used in series to fulfil this function. This combination is called an LC low pass filter. The properties of an inductor smooth the current flow, while the capacitor resists sudden changes in voltage. The combined effect produces a relatively smooth voltage output with low ripple. For example, if the input voltage is 10V and the switch employs a duty cycle of 50%, the output voltage will be 5V.

A further necessary component of a Buck Converter is to incorporate a diode or other switch in parallel with the inductor. This is to compensate for the property of an inductor, in that the current in an inductor cannot instantly change, protecting the switching transistor from being overloaded and destroyed.

Buck Converters also incorporate additional circuitry to ensure a stable output voltage. The converter uses a closed-loop control scheme with negative feedback to monitor the voltage output and dynamically adjusts the duty cycle of the switch to regulate the output voltage.

Design considerations

  • Buck Converters are very efficient, with some devices offering efficiencies of above 95%.
  • Buck Converters can be more cost-effective than linear regulators at higher power levels, the cost of removing the heat generated by a linear regulator may be less than employing a Buck Converter.
  • The output of a Buck Converter will feature a noise, meaning the more stable output of a linear voltage regulator is better suited for application requiring low output noise.
  • Linear regulators can respond faster to input and output changes versus a buck converter.

...
Read more Read less

Filters

Viewing 1 - 20 of 535 products
Results per page
Description Price Maximum Output Current Maximum Output Voltage Regulator Function Minimum Output Voltage Minimum Input Voltage Maximum Input Voltage Output Type Mounting Type Series Number of Outputs Pin Count Package Type Switching Regulator Line Regulation
RS Stock No. 533-4140
Mfr. Part No.LM2673S-ADJ/NOPB
PHP320.53
Each
units
3A 37 V Buck Controller 1.2 V 8 V 40 V Adjustable Surface Mount - 1 7 D2PAK (TO-263) Yes -
RS Stock No. 920-3649
Mfr. Part No.LM2673S-ADJ/NOPB
PHP272.685
Each (In a Tube of 45)
units
3A 37 V Buck Controller 1.2 V 8 V 40 V Adjustable Surface Mount - 1 7 D2PAK (TO-263) Yes -
RS Stock No. 460-487
Mfr. Part No.LM2576HVS-ADJ/NOPB
PHP332.37
Each
units
3A 57 V Buck Controller, Inverting 1.23 V 4 V 60 V Adjustable Surface Mount - 1 5 D2PAK (TO-263) Yes -
RS Stock No. 923-2534
Mfr. Part No.LM2576HVS-ADJ/NOPB
PHP308.70
Each (In a Tube of 45)
units
3A 57 V Buck Controller, Inverting 1.23 V 4 V 60 V Adjustable Surface Mount - 1 5 D2PAK (TO-263) Yes -
RS Stock No. 920-3595
Mfr. Part No.LM2596S-ADJ/NOPB
PHP265.482
Each (In a Tube of 45)
units
3A 37 V Buck Controller, Inverting 1.2 V 4.5 V 40 V Adjustable Surface Mount - 1 5 D2PAK (TO-263) Yes -
RS Stock No. 533-3715
Mfr. Part No.LM2596S-ADJ/NOPB
PHP309.44
Each
units
3A 37 V Buck Controller, Inverting 1.2 V 4.5 V 40 V Adjustable Surface Mount - 1 5 D2PAK (TO-263) Yes -
RS Stock No. 533-8091
Mfr. Part No.LM2576T-5.0/NOPB
PHP151.26
Each
units
3A - Buck Controller, Inverting - 4 V 40 V Fixed Through Hole - 1 5 TO-220 Yes -
RS Stock No. 920-3514
Mfr. Part No.LM2576S-ADJ/NOPB
PHP154.35
Each (In a Tube of 45)
units
3A 37 V Buck Controller, Inverting 1.23 V 4 V 40 V Adjustable Surface Mount - 1 5 D2PAK (TO-263) Yes -
RS Stock No. 533-3232
Mfr. Part No.LM2576S-ADJ/NOPB
PHP179.95
Each
units
3A 37 V Buck Controller, Inverting 1.23 V 4 V 40 V Adjustable Surface Mount - 1 6 D2PAK (TO-263) Yes -
RS Stock No. 100-3981
Mfr. Part No.LM2576T-5.0/NOPB
PHP128.625
Each (In a Tube of 45)
units
3A - Buck Controller, Inverting - 4 V 40 V Fixed Through Hole - 1 5 TO-220 Yes -
RS Stock No. 533-3759
Mfr. Part No.LM2596T-ADJ/NOPB
PHP260.34
Each
units
3A 37 V Buck Controller, Inverting 1.2 V 4.5 V 40 V Adjustable Through Hole - 1 5 TO-220 Yes -
RS Stock No. 920-3605
Mfr. Part No.LM2596T-ADJ/NOPB
PHP221.235
Each (In a Tube of 45)
units
3A 37 V Buck Controller, Inverting 1.2 V 4.5 V 40 V Adjustable Through Hole - 1 5 TO-220 Yes -
RS Stock No. 100-3978
Mfr. Part No.LM2575T-5.0/NOPB
PHP124.509
Each (In a Tube of 45)
units
1A - Buck Controller, Inverting - 4 V 40 V Fixed Through Hole - 1 5 TO-220 Yes -
RS Stock No. 533-8063
Mfr. Part No.LM2575T-5.0/NOPB
PHP146.63
Each
units
1A - Buck Controller, Inverting - 4 V 40 V Fixed Through Hole - 1 5 TO-220 Yes -
RS Stock No. 920-3586
Mfr. Part No.LM2596S-5.0/NOPB
PHP265.482
Each (In a Tube of 45)
units
3A - Buck Controller, Inverting - 4.5 V 40 V Fixed Surface Mount - 1 5 D2PAK (TO-263) Yes -
RS Stock No. 533-3692
Mfr. Part No.LM2596S-5.0/NOPB
PHP312.30
Each
units
3A - Buck Controller, Inverting - 4.5 V 40 V Fixed Surface Mount - 1 5 D2PAK (TO-263) Yes -
RS Stock No. 545-7849
Mfr. Part No.PTN78020WAH
PHP1,450.73
Each
units
6A - Buck Controller - - - - Through Hole - 1 7 DIP Module Yes ±10
RS Stock No. 121-8929
Mfr. Part No.PTN78020WAH
PHP1,472.891
Each (In a Tube of 20)
units
6A - Buck Controller - - - - Through Hole - 1 7 DIP Module Yes ±10
RS Stock No. 533-4178
Mfr. Part No.LM2673T-ADJ/NOPB
PHP267.03
Each
units
3A 37 V Buck Controller 1.2 V 8 V 40 V Adjustable Through Hole - 1 7 TO-220 Yes -
RS Stock No. 121-9724
Mfr. Part No.LM46002PWPT
PHP179.55
Each (On a Reel of 250)
units
2A 28 V Step Down 1 V 3.5 V 60 V Adjustable Surface Mount - 1 16 HTSSOP Yes -