EVAL-CN0523-EBZ

USB-Powered, 5.8 GHz RF Power Amplifier with Overtemperature Management

Overview

The EVAL-CN0523-EBZ is a USB-powered, RF power amplifier that is optimized for transmitting signal chains in the 5.8GHz ISM band. Using two HMC407 amplifiers cascaded together, the design provides a gain of 28dB and return losses of more than 10dB throughout its RF band of operation.

An overtemperature management feature is implemented on the EVAL-CN0523-EBZ wherein the amplifiers are automatically disabled when the board temperature reaches a preset threshold, and it automatically returns to normal operation once the temperature falls below the hysteresis point.

Designed to be used with the ADALM-PLUTO, or other software defined radio platform, the board features a small form factor, with dimensions of 25.4mm × 50.8mm x 1.5748mm (PCB only). The RF input and output are designed with a 50Ω impedance, enabling direct connection between the circuit and standard 50Ω systems.

A micro-USB connector is used for the input power, allowing the evaluation board to use most 5V wall wart power supplies available in the market.

https://media.githubusercontent.com/media/analogdevicesinc/documentation/main/docs/solutions/reference-designs/eval-cn0523-ebz/cn0523_simplified_block_diagram.png

Figure 1 EVAL-CN0523-EBZ Block Diagram

Reference Design Hardware

Primary Side

https://media.githubusercontent.com/media/analogdevicesinc/documentation/main/docs/solutions/reference-designs/eval-cn0523-ebz/top_temp.jpg

Figure 2 CN0523 Primary Side

SMA Connectors

The SMA connectors are used for the RF input and output connections:

  • J1 is the RF Input SMA male connector that would be connected to a radio or piece of RF equipment. The maximum RF input level of the EVAL-CN0523-EBZ is +10dBm. Do not use a higher input level to avoid damaging the circuit.

  • J2 is the RF Output SMA FEmale connector that would be connected to an antenna. The saturated output power (Psat) of EVAL-CN0523-EBZ is +27dBm. Ensure that the RF load can handle the amplified RF signal. Use an RF attenuator if necessary to avoid damage.

LED Indicators

The reference design uses two LEDs to indicate its current status:

LED Indications of Board Status

DS1

DS2

Board Status

Off

Off

No power

Off

On

Normal operation

On

On

Overtemperature

Secondary Side

https://media.githubusercontent.com/media/analogdevicesinc/documentation/main/docs/solutions/reference-designs/eval-cn0523-ebz/bot_temp.jpg

Figure 3 CN0523 Secondary Side

Power Supply Connector

  • P1 is the micro-USB port used to provide 5V power to the board. The total typical supply current of the on-board RF amplifiers is 230mA.

Changing the Temperature Switch Trip Point (JP1, JP2, JP3)

  • The trip point of the temperature switch can be set using the solder jumpers JP1, JP2, and JP3 as shown in the table below. When the board temperature reaches the trip point, the ADT6401 will disable the two RF amplifiers.

    https://media.githubusercontent.com/media/analogdevicesinc/documentation/main/docs/solutions/reference-designs/eval-cn0523-ebz/jmp_settings.jpg

    Figure 4 ADT6401 Jumper Settings

Selecting a Trip Point for the ADT6401

JP1 Setting

JP2 Setting

JP3 Setting

Trip Point

2 & 3

2 & 3

2 & 3

+45°C

1 & 2

2 & 3

2 & 3

+55°C

No solder jumper

2 & 3

2 & 3

+65°C

2 & 3

1 & 2

2 & 3

+75°C

1 & 2

1 & 2

2 & 3

+85°C

No solder jumper

1 & 2

2 & 3

+95°C

2 & 3

2 & 3

1 & 2

+65°C

1 & 2

2 & 3

1 & 2

+75°C

No solder jumper

2 & 3

1 & 2

+85°C

2 & 3

1 & 2

1 & 2

+95°C

2 & 3

No solder jumper

2 & 3

+105°C

1 & 2

No solder jumper

2 & 3

+115°C

No solder jumper

No solder jumper

2 & 3

+55°C

Important

Due to the considerable thermal dissipation of the RF amplifiers, the last three options should not be used.

Getting Started

Required Equipment

Hardware

Firmware

  • For step-by-step procedure on how to update the Pluto Firmware, you can use this user guide link. The latest firmware version for the ADALM-PLUTO can be found here:

    download

    ADALM-PLUTO Firmware: Pluto version latest release

  • In order to properly operate the ADALM PLUTO, you need to setup and configure it. Follow the procedure through this link.

Test Setup

  1. Connect directly the TX port of ADALM-PLUTO to the RF Input (J1) of the EVAL-CN0523-EBZ.

  2. Connect directly the RX port of the ADALM-PLUTO to a 30dB attenuator.

  3. Connect RF Output (J2) of the EVAL-CN0523-EBZ to a 30dB attenuator using a male-to-male SMA cable.

  4. Connect P1 (micro-USB) connector of the EVAL-CN0523-EBZ into a PC USB port or a 5V USB charger.

  5. Connect the micro-USB to USB cable to a PC/laptop and the other end to the ADALM-PLUTO data port.

  6. The DS2 LED of EVAL-CN0523-EBZ will automatically turn on, indicating that the board is powered on and is in operation.

  7. Refer to the image below for the full hardware setup.

    https://media.githubusercontent.com/media/analogdevicesinc/documentation/main/docs/solutions/reference-designs/eval-cn0523-ebz/full_hw_setup.jpg

    Figure 5 EVAL-CN0523-EBZ Test Setup

Warning

Connecting the CN0523 directly to the PlutoSDR input (Rx) may result in an exceedance of its absolute maximum ratings of +2.5dBm. Such an action may lead to permanent damage to the PlutoSDR. It is strongly recommended to use a 30dB or 40dB attenuator at the RX input of the ADALM PLUTO to avoid incurring damage.

Schematic, PCB Layout, Bill of Materials

Download

EVAL-CN0523-EBZ Design & Integration Files

  • Schematics

  • PCB Layout

  • Bill of Materials

  • Gerber Files

  • Allegro Board File

Help and Support

For questions and more information about this product, connect with us through the Analog Devices EngineerZone.