48-V / 25-A negative-to-positive synchronous buck-boost reference design for power amplifiers


Design files


This reference design is a negative-to-positive synchronous buck-boost converter for power amplifier applications. The circuit is powered from the nominal -48-V system source to provide an output voltage of +48 V at 25 A. The design uses two dual synchronous boost controllers for 4-phase operation at a switching frequency of 150 kHz. Output voltage adjustment to +30 V is jumper selectable. 1- through 4-phase operation is also jumper selectable.

  • Non-isolated inverting solution for higher power
  • Excellent phase current sharing for balanced thermal performance
  • Jumper selectable phase control
  • Compact design for minimum solution size
  • Jumper selectable output voltage control
Output voltage options PMP21943.1
Vin (Min) (V) -60
Vin (Max) (V) -36
Vout (Nom) (V) 48
Iout (Max) (A) 25
Output Power (W) 1200
Isolated/Non-Isolated Non-Isolated
Input Type DC
Topology Buck Boost- Synchronous
Communications equipment
?? View video with transcript Video

A fully assembled board has been developed for testing and performance validation only, and is not available for sale.

Design files & products

Design files

Download ready-to-use system files to speed your design process.

TIDT133.PDF (2637 K)

Test results for the reference design, including efficiency graphs, test prerequisites and more

TIDM166.PDF (698 K)

Detailed schematic diagram for design layout and components

TIDM167.PDF (108 K)

Complete listing of design components, reference designators, and manufacturers/part numbers

TIDM168.PDF (337 K)

Detailed overview of design layout for component placement

TIDM170.ZIP (2693 K)

Files used for 3D models or 2D drawings of IC components


Design file that contains information on physical board layer of design PCB

TIDM169.PDF (3066 K)

PCB layer plot file used for generating PCB design layout


Includes TI products in the design and potential alternatives.

Buck-boost & inverting controllers (external switch)

LM5170-Q1Multiphase bidirectional current controller, AEC-Q100 qualified

Data sheet: PDF | HTML

TLV7021Low power, small size comparator with open-drain output

Data sheet: PDF | HTML
General-purpose op amps

LM8261Single 30-V 21-MHz operational amplifier

Data sheet: PDF | HTML
Isolated DC/DC converters & modules

LM50187.5-100V Wide Vin, 300mA Constant On-Time Synchronous Buck Regulator

Data sheet: PDF | HTML
Isolated gate drivers

UCC21225A2.5kVrms, 4A/6A dual-channel isolated gate driver with dual input, 5V UVLO & LGA package

Data sheet: PDF | HTML
Linear & low-dropout (LDO) regulators

TPS709150-mA, 30-V, ultra-low-IQ, low-dropout voltage regulator with reverse current protection and enable

Data sheet: PDF | HTML
Shunt voltage references

LM4040-N100-ppm/°C precision micropower shunt voltage reference

Data sheet: PDF

Technical documentation

= Top documentation selected by TI
No results found. Please clear your search and try again.
View all 1
Type Title Date
* Test report 48-V / 25-A Negative-to-Positive Synchronous Buck-Boost Reference Design Sep. 10, 2019

Support & training

TI E2E™ forums with technical support from TI engineers

View all forum topics

Content is provided "as is" by TI and community contributors and does not constitute TI specifications. See terms of use.

If you have questions about quality, packaging or ordering TI products, see TI support. ​​​​​​​​