Part Number: TPS7B67-Q1
Dear Linear Requlators team
I will use TPS7B67-Q1 that controlled ADJ by MCU as a below.
We had spec which input: 9V ~ 16V, ouput: 8V, 5V, 3.3V@200mA
Can we use ADJ pin by MCU as a above picture?
Yes, but I would recommend the following change: Add another resistor to ground from the circled node.
This ensures there is a lower divider resistor in place on power up in case the MCU pins are high impedance or undefined state during boot and all of the transistors are off for resistors 1, 2, and 3. This new resistor should be set for your 3.3 V output. Then you can turn on a transistor to switch in a parallel resistor to increase the output voltage to 5 V or 8 V.
Also, watch your power dissipation. What are your operating ambient temperatures? Do you have any forced air cooling?
16 V input, 3.3 V @ 200 mA output Power dissipation = 2.54 W.
Eric Preiss | Applications and Validation Engineer | Linear and Low Dropout Regulators | Texas Instruments
In reply to Eric.Preiss:
Thank you for your kindly reply
We will use schematices as a red round below. is it correct?
Thanks a lot
In reply to Gerald Choi:
All content and materials on this site are provided "as is". TI and its respective suppliers and providers of content make no representations about the suitability of these materials for any purpose and disclaim all warranties and conditions with regard to these materials, including but not limited to all implied warranties and conditions of merchantability, fitness for a particular purpose, title and non-infringement of any third party intellectual property right. TI and its respective suppliers and providers of content make no representations about the suitability of these materials for any purpose and disclaim all warranties and conditions with respect to these materials. No license, either express or implied, by estoppel or otherwise, is granted by TI. Use of the information on this site may require a license from a third party, or a license from TI.
TI is a global semiconductor design and manufacturing company. Innovate with 100,000+ analog ICs andembedded processors, along with software, tools and the industry’s largest sales/support staff.