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EVAL-CN0196-EB1Z Overview

CN0196 is an H-bridge composed of high power switching MOSFETs that are controlled by low voltage logic signals. The circuit provides a convenient interface between logic signals and the high power bridge. The bridge uses low cost N-channel power MOSFETs for both the high and low sides of the H-bridge. The circuit also provides galvanic isolation between the control side and power side. This circuit can be used in motor control, power conversion with embedded control interface, lighting, audio amplifiers, and uninterruptable power supplies (UPS). Modern microprocessors and microconverters are generally low power and operate on low supply voltages. Source and sink current for 2.5 V CMOS logic outputs ranges from μA to mA . Driving an H-bridge switching 12 V with a 4 A peak current requires the use of carefully selected interface and level translation components, especially if low jitter is needed.

The ADG787 is a low voltage CMOS device that contains two independently selectable single-pole double-throw (SPDT) switches. With a 5 V dc power supply, a voltage as low as 2 V is a valid high input logic voltage. Therefore, the ADG787 provides appropriate level translation from the 2.5 V controlling signal to the 5 V logic level needed to drive the ADuM7234 half-bridge driver.

The ADuM7234 is an isolated, half-bridge gate driver that employs Analog Devices’ iCoupler® technology to provide independent and isolated high-side and low-side outputs making it possible to use N-channel MOSFETs exclusively in the H-bridge. There are several benefits in using N-channel MOSFETs: N-channel MOSFETs typically have one third of the on resistance of P-channel MOSFETs and higher maximum current; they switch faster, thereby reducing power dissipation; and the rise time and fall time is symmetrical.

The 4 A peak drive current of the ADuM7234 ensures that the power MOSFETs can switch on and off very fast, thereby minimizing the power dissipation in the H-bridge stage. The maximum drive current of the H-bridge in this circuit can be up to 85 A, which is limited by the maximum allowable MOSFET current.

The ADuC7061 is a low power, ARM7 based precision analog microcontroller with integrated pulse width modulated (PWM) controllers that have outputs that can be configured to drive an H-bridge after suitable level translation and conditioning.

Equipment Needed

  • PC with a USB port and Windows XP, Windows Vista (32-bit), or Windows 7 (32-bit)
  • EVAL-CN0196-EB1Z circuit evaluation board
  • EVAL-ADuC7061MKZ evaluation board
  • DC supply or battery: +12 V, 10 A
  • Load, such as Coilcraft SER2014-402 power inductor
  • Oscilloscope with current probe

General Setup

EVAL-ADuC7061MKZ
PWRIN J1-1 +5V_2 J1-1
GND J1-2 GND2 J1-2
PWM1 J2-25 PWM1_I J1-4
PWM0 J2-26 PWM0_I J1-5

Test Setup Functional Block Diagram

Connectors and Jumper Configurations

Software and Driver Installation

It is recommended that you install the CN0196 SDP Evaluation Software to the default directory path C:\Program Files\Analog Devices\CN0196\ and all National Instruments products to C:\Program Files\National Instruments\
  • Follow the on screen prompts to install the software





Downloading Firmware to EVAL-ADuC7061-MKZ

  • Connect the EVAL-ADuV7061-MKZ to the PC using USB cable, then find the port assigned to this board in the Device Manager.

  • Open the software ”ARMWSD.exe” located in the ARMWSD folder, or C:\Program Files\Analog Devices\CN0196\ARMWSD\ARMWSD.exe.

  • Click the Configure button, Go to Parts tab and select ADuC7061, go to Comms Tab and set the serial port according to the port number indicated on PC device manager and set the baud rate to 9600 as seen in below image.

  • Change tab to Commands, set the Flash and Run selection according to the image below.

  • After setting the configuration, click “Browse” and select file “PWM Generator for EVAL-CN0196-EB1Z.hex” found in the EVAL-ADuC7061-MKZ Firmware folder. Then click start, and a message tells how to download the firmware, Press S2 on EVAL-ADuC7061-MKZ, and hold it down, and meanwhile click the S1 on EVAL-ADuC7061-MKZ. After the downloading process “Flashing Complete”, Click the Run button.

Using Evaluation Software

Software Front Panel

Descriptions:

  1. Connect: Provides connection between EVAL-CN0196-EB1Z and EVAL-ADuC7061-MKZ boards.
  2. Disconnect:
  3. Stop APP:
  4. Load Configuration:
  5. VDD:
  6. Inductor:
  7. Enable:
  8. Maximum Current:
  9. PWM Waveform:
  10. PWM Configuration:
  11. PWM Pulse Width:
  12. PWM Interval:
  13. Stop:
  14. High Side Shot:
  15. Low Side Shot:
  16. Reset:
  17. Current Wave:
resources/eval/user-guides/circuits-from-the-lab/cn0196.1512543411.txt.gz · Last modified: 06 Dec 2017 07:56 by glai