User`s manual

ManualsBrandsMaestro ManualsGPSA2100-A

PRELIMINARY

V0.5 – Feb-11 User’s Manual Page 19 of 22

10 Board Schematics

The following shows the schematics of the EVA2100. For best readability the picture

was enlarged to cover the complete page.

Please note that the design is done in a way that it reflects the Minimum

Configuration as outlined in the GPS Receiver Manual A2100! These are especially:

• The A2100-A needs an external pull-up resistor to be configured for UART

operation. Although first firmware releases will work with the UART interface

by default future releases will not. Please consider the pull-up resistor in your

design or pull the GPIO up right after reset by other means.

• The ON_OFF input of the A2100-A needs to be connected to a push-pull

output of a microprocessor. For a wake-up, including the initial one after power

on, a LOW-HIGH transmission is mandatory.

• The nRST pin of the A2100-A needs to be connected to an open collector /

open drain output of a microprocessor! This is necessary to work with

SiRFaware

. Pulling nRST low and afterwards toggling of ON_OFF will get

the module to report a position fix when in SiRFaware

mode.

The following picture shows the minimum configuration for using the A2100-A in

UART mode with a passive antenna. In addition BOOTSEL and VANT are supported

on the evaluation board!

A2100-A

GSD4e

UART

ON_OFF

GND

3.3V

ANT_EXT

ANT_GND

Vcc

Shown from top without lid; pads shown for better understanding

Pin 1

marker

10kΩ

nRST