1)Does the EB-3531 support a low power mode? Can pins 9 or 10 be used to do this, or do I have to remove the power to VCC and run off VBAT to achieve this?
2)Do the TXA and TXB pins go high impedance when the ON_OFF pin is pulled high? Or again, do I need to remove the power to VCC to get these to go high impedance?
The data sheet is not clear about the exact operation of the RF_PWR and ON_OFF pins.
Please check below for our engineers' response:
1) Low power mode in SiRF chipset is referred to Trickle Power mode and this is not available in the current SiRF firmware. Also, the device firmware does not include it as default. Removing the power of VCC and VBAT turns on the EB-3531 and goes through the Cold Start process.
2) The ON-OFF pin should be pulled low; please refer to Page 7 of its user manual (please check your email). Moreover, under general user case scenario, please do not connect the ON_OFF pin to anything. Just leave it floating. Then, the EB-3531 will turn on automatically without special control.