LTC3676 PMIC, Linux Beta Drivers & Development Board Now Available for i.MX6

LTC3676 datasheet

 

Features

  • Quad I2C Adjustable High Efficiency Step Down DC/DC Converters: 2.5A, 2.5A, 1.5A, 1.5A
  • Three 300mA LDO Regulators (Two Adjustable)
  • DDR Power Solution with VTT and VTTR Reference
  • Pushbutton ON/OFF Control with System Reset
  • Independent Enable Pin-Strap or I2C Sequencing
  • Programmable Autonomous Power-Down Control
  • Dynamic Voltage Scaling
  • Power Good and Reset Functions
  • Selectable 2.25MHz or 1.12MHz Switching Frequency
  • Always Alive 25mA LDO Regulator
  • 12μA Standby Current
  • Low Profile 40-Lead 6mm × 6mm × 0.75mm QFN Package

 

LTC3676 Typical Application

 


Linux Driver Instructions (Please note that this is a Beta Release Version)

 

The driver is good reference code to illustrate how to communicate with LTC3676 via I2C.

The .zip file also includes a test app and readme.txt with instructions. It has been tested with i.MX6Q NovPek board from NovTech.

It is configured for the LTC3676-1 but also support LTC3676 by simply changing a flag and there are comments about the minor difference between the -1 and non-1 for the driver.

Here is the description and instructions also contained in the included readme file:

This package contains the linux driver for LTC3676 and LTC3676-1. It has been tested with i.MX6Q. It also includes a test app.

It is configured for the LTC3676-1 but there are internal comments about the minor difference between the -1 and non-1 for the driver.

Here are general instructions on how to include this new driver in the Linux build using ltib. You can also see that it is tested with linux-3.0.35 that Freescale has used for i.MX6.

1) cd ltib/rpm/BUILD/linux-3.0.35 (Where your Ltib folder is stored).

2) extract zip file: tar -zxpf LTC3676_Driver.tar.gz

3) Run LTIB configure: ./ltib -c

4) Select "Configure the kernel", exit, and yes to save.

5) When Kernel Menu appears, select "Device Drivers".

6) Select "Voltage and Current Regulator Support".

7) Select "Linear LTC3676 Regulator Driver" to compile into kernel. Don't build as a module.

8) Exit and Save.

9) Ltib should build the kernel with the driver.

Application Instructions:

This builds in the ltc3676_1_test application to allow a user to check the regulators and dynamically change the voltage on the ARM core rail. The voltage movement is small to not push the i.MX6 outside normal operation. This test application does not have any overvoltage error checking for safety. It also does not change the processor frequency. It just tests the basic LTC3676 driver operation.

1) cd ltib (Where your Ltib folder is stored).

2) Run "./ltib -m prep -p imx-test"

3) Move the ltc3676_test folder extracted from this tar file:

"mv rpm/BUILD/linux-3.0.35/ltc3676_test
rpm/BUILD/imx-test-12.09.01/test/."

4) Run "./ltib -m scbuild -p imx-test"

5) Run "./ltib"

6) Burn SD Card, "./mk_mx6_sd -ukr /dev/sdb", /dev/sdb is the name of the SD card.

7) Safely Remove SD Card and install in NOVPEK board.

8) Power and boot to Linux.

9) Run "cd /unit_test "

10) Run Application, ./ltc3676_1_test

 

i.MX6 Board from NovTech (Click on this link)

 

Schematics for LTC3676-1 Linear Technology Power
Plug in Board available.

 

Contact your local Linear Technology sales office Gerard Velcelean (gvelcelean@linear.com) or Steve Knoth (sknoth@linear.com) if you have any questions.