L6480: Power & Comm problem

hj_smith · ‎2014-08-21

Posted on August 21, 2014 at 16:45

I'm currently experiencing a problem in which I cannot get the L6480 device to communicate - I think this may be due to a device power up fault but I was hoping someone on here could help!

I've attached a simplified version of the circuit diagram, outlining the power connections that I've made in my design - if I've made any mistakes with the power connections then please let me know! The host device is an 8 bit Atmel AVR device (ATmega32A), and I'm working with +5V logic and a motor supply of +24V.

I measured the voltages on the power pins to be:

VS - +24V

VBOOT - +24V

VSREG - +24V

VCC - +2V5 (!?)

VCCREG - +3V3

VREG - +3V3

VDD - +5V

I think the device is still in 'power-up' condition as VCC is below the minimum as stated in section 6.1 of the datasheet, and also the 2MHz signal coming from the OSCOUT pin is neither a square wave or a sine wave which I would have assumed it would be?

I've attached an image of the actual signal from an oscilloscope which shows the waveform that I'm getting.

Any feedback will be greatly appreciated!!!

#spi #power-up #cspin #l6480

Enrico Poli · ‎2014-09-21

Posted on September 22, 2014 at 08:52

Hello,

did you check the STBY\RESET signal? When it is low, the VCC regulator is disabled.

Regards

Enrico

hj_smith · ‎2014-11-05

Posted on November 05, 2014 at 15:02

The STBY/ RESET pin is now being driven high by the microcontroller but I'm still having the same problems. What sort of waveform should I be seeing on the OSCOUT pin?

Enrico Poli · ‎2014-11-17

Posted on November 17, 2014 at 10:45

The OSCOUT waveform is a series of pulses with a frequency of 2 MHz.(the duty cycle is not 50%).