Maxim Solution Example丨Latest Isolated Power Supply Reference Design

Isolated power supply is one of the challenges faced by industrial and medical equipment power supply design. Based on the company's advanced isolated DC-DC control technology, Maxim power engineers have developed a series of isolated power supply reference designs to help users simplify power supply design. Each power module can provide transformer products from different manufacturers (Hanren, Sumida, Halo, Wurth), making it convenient for users to obtain key components of isolated power supply from the market. This series of products converts 24V industrial power into different output voltages and provides different levels of output power (Table 1). Each design has been rigorously tested and provides test data such as power regulation, load regulation, efficiency, output voltage ripple and transient characteristics.

The modular design can be easily installed directly on the user's circuit board. Circuit schematics, design files, PCB files and BOM are also provided. Users can easily transplant the selected isolation module design into the terminal product.

• Industrial Control and Industrial Automation
  

• Medical imaging, electrocardiographs

• High efficiency: reduce power consumption and simplify heat dissipation design

• Compact structure and flexible design: highly integrated

• High reliability, meeting the demanding requirements of industrial and medical environments

• Undervoltage and overvoltage protection

• Iso-BUCK and No-Opto Flyback topologies do not require optocouplers

• Flexible selection of transformers from different manufacturers

• Wide input voltage range: 17V - 36V

• MAXREFDES124# input range: 9V - 18V

• MAXREFDES1194# input range: 6V-60V

• Output tolerance: ±5%

• Output current (continuous): 120% of nominal value

• Ripple <±1.5%Vo

• High efficiency (see corresponding reference design document)

• 1500V electrical isolation

• MAXREFDES124# provides 5kV isolation

Table 1. Typical parameters

The MAXREFDES111# is a high-efficiency flyback topology isolated power supply that converts a 24V (17V-36V) input into a 5V output with an output power of 2W (0.4A). The design uses the MAX17498B 500kHz peak current-mode converter.

MAXREFDES112# and MAXREFDES113# are high-efficiency flyback topology isolated power supplies that convert 24V (17V-36V) input into 12V output, with output power up to 10W (0.8A) and 20W (1.6A) respectively. The design uses the MAX17596 peak current mode converter with switching frequencies of 500kHz and 200kHz respectively.

MAXREFDES112#

MAXREFDES113#

MAXREFDES114#, MAXREFDES115#, MAXREFDES116#, and MAXREFDES1051# use the MAX17599 high-efficiency, active-clamp forward, current-mode controller optimized for industrial power supplies. They convert 24V input (17V-36V) to 5V or 24V output, with maximum output powers of 10W (2A), 20W (4A), 40W (8A), and 48W (24V@2A), respectively.

MAXREFDES121# and MAXREFDES122# use active clamp topology to convert 24V input (17V-36V) to 3.3V and 5V output respectively, with output power up to 40W (3.3V@12A, 5V@8A). The circuit uses the MAX17599 active clamp, current mode PWM controller, optimized for industrial applications, and the entire circuit occupies a board area of ​​22mm x 70mm.

MAXREFDES114# - MAXREFDES116#, MAXREFDES121, MAXREFDES122, MAXREFDES1051 Block Diagram

MAXREFDES116#

MAXREFDES119# and MAXREFDES120# use a flyback topology without an optocoupler to convert a 24V input (17V-36V) to a 5V output, with output powers of 10W (2A) and 20W (4A) respectively. The circuit is based on the MAX17690 fixed-frequency, peak current-mode converter and uses Maxim's advanced primary-side feedback technology, eliminating the need for optocoupler feedback, simplifying the design while effectively reducing costs. The MAX17606 secondary-side synchronous rectification MOSFET driver greatly improves operating efficiency and reduces the burden of heat dissipation design.

MAXREFDES124# uses a flyback topology without optocouplers to convert 12V input (9V-18V) to 5.5V output with an output power of up to 22W (4A). The circuit is based on the MAX17690 fixed-frequency, peak current-mode converter and uses Maxim's advanced primary-side feedback technology, which eliminates the need for optocoupler feedback, simplifying the design while effectively reducing costs. The MAX17606 secondary-side synchronous rectification MOSFET driver greatly improves operating efficiency and reduces the burden of thermal design. It is worth emphasizing that the transformer used in this module can provide up to 5kV of electrical isolation, meeting medical and other applications with higher isolation requirements.

MAXREFDES1194# adopts the flyback topology without optocoupler to convert 24V input (6V-60V) into 5 isolated outputs, which features wide input voltage range and multiple isolated outputs. The circuit is based on the MAX17690 fixed frequency, peak current mode converter and uses Maxim's advanced primary feedback technology, thus eliminating the need for optocoupler feedback, effectively reducing costs while simplifying the design.

MAXREFDES119#, MAXREFDES120#, MAXREFDES124# block diagram

MAXREFDES124#

MAXREFDES1194#

MAXREFDES1163# - MAXREFDES1170 # use isolated BUCK topology to convert 24V input (17V-32V) to single or multiple outputs such as 15V, ±15V, ±12V, with an output power of about 3W. The circuit is based on the MAX17681 isolated BUCK converter, and stabilizes the output voltage through primary feedback, thereby eliminating the need for optocoupler feedback, simplifying the design and effectively reducing costs. This series of products is based on 6 MAX17681 evaluation board designs, modularizing the evaluation board, and its size is 1/4 of the evaluation board, and adding domestic transformer options to reduce the overall cost of the power supply.

MAXREFDES1163# - MAXREFDES1170# Block Diagram

MAXREFDES1163#