LAUNCHXL2-570LC43: No other accessory attached, plug usb, but current limit LED is showing

Hi Hongbo,

I started to work on your issue and i will get back to you soon.

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Thanks,

Jagadish.

Hello I made some measurements:

the TPS2553 OUT pin is 0V, ILIM output is 0V. The IN is 5V, EN is 5V.

Is it possible the TPS2553 switching is broken?

I have disconnected JP6 to use external power source ( from Boostxl-DRV8301 3.3V), the chip and Debug Probe (TM4C) both works

Hi

The FAULT of TPS2553 is asserted (active low) during an overcurrent, overtemperature, or reverse-voltage condition. It seems to me that there is a circuit short somewhere on your board.

If you disconnect JP6 and use external power supply from J17, does the TMS570LC43x work? What is the current consumption? If no code is running on LC43x, the current consumption of the launchpad is around 200mA (5V). 

I used power supply by Booster Pack DRV8301, and the TMS570LC43x works. I am using USART + ADC1 + fast toggling two user LEDs, the current consumption is around 350mA

I inspected the board it does not have shorted circuit on board.

The current limit of this board is about 500mA (5V) with Rilm=48kohms. If the Booster Pack consumes too much current, it will trigger the TPS2553 to shutdown the power supply and turn on the LED9.

It is OK to power the launchpad using the booster pack.

I know.

when I didn't plug any thing on the launch pad, the TPS2553 showed current limit, the whole board doesn't work.

I disconnected JP6 and used Booster Pack as a power supply is to confirm the Debug Probe IC and tms570lc43x IC are working.

Hi Hongbo,

Can you measure the value of resistor: R43 and R45? The current limit of launchpad is 500mA at 5V (2.5watts).

You said the current is 350mA when the CPU is running code for ADC/ED/UART. This current consumption will not shut down the TPS2553.

I measured the R43 and R45 are the value shown in schematic.

Can it be broken in TPS2553?

Hi Hongbao,

Can you try a smaller resistor for R43, for example 160K or 120K? The smaller the R43 is, the higher the current limit.

But the board was working correctly, it was broken after a night.

I am now using an external power source, and ordered another board