Hi,

is there a distinct difference between the two functions?
right now, im testing my prototype, calibrating it as a compass with
the voltage responding to the compass direction.
once calibrated (with reference to HMR3000), this can be also used
for detction of earth's magnetic field, am i right?

update on my progress: yup, i would need to increase my 270 resistor
to a higher value because loading effect will occur, as the bridge
resistance of the hmc1022 is typically 1.1k at 5V. that's why my
output voltage from the amplifier is little as the input voltage from
the sensor is drained.

im intending to change my 270 to 1.5k and use 330k as feedback thus a
gain of 220. is this sufficient?
i'm using the best straight line (+/- 1Gauss) as stated in the
datasheet: -4mV to 8mV

if im using 8v supply, my vref would be 4v, my cutoff would be 6.5v

Any recommendations on ADC? im thinking of using ADS8320. Any
comments?

thanks all for your reply and inputs.

regards,
Resham A R


--- In magnetometer@yahoogroups.com, "MarkD" <mdennisond@...> wrote:
>
> Hi,
>
> Are you using this to detect changes in the Earth's magnetic field
or just
> for a digital compass ?
>
>
>
> Mark
>
>
>
>
>
>
>
> From: magnetometer@yahoogroups.com
[mailto:magnetometer@yahoogroups.com] On
> Behalf Of resham_84
> Sent: 11 December 2008 07:24
> To: magnetometer@yahoogroups.com
> Subject: [magnetometer] Comments needed for my 3-axis magnetometer
(using
> HMC1022) design
>
>
>
> Hi all, i'm currently doing a 3-axis magnetometer using 2 HMC1022
> chips. However, i'm unsure if my schematic design is appropriate.
Can
> somebody shed some light on my design or anyone that have
experience in
> using HMC1022.
>
> Current stage for my breadboard prototype is on the sensor and
> amplification module. I need advice on amplification factor,
Vsupply
> and whether i have setup correctly.
>
> ps: i have uploaded my schematic under Files. (3-Axis Magnetometer
> using HMC1022)
>
> The Set/Reset Circuitry and the Offset Straps are not yet
implemented
> at this stage.
>
> Thanks in advance.
>
>
>
>
>
> [Non-text portions of this message have been removed]
>