HMC6343 Honeywell, HMC6343 Datasheet - Page 6

• Manufacturer Part Number: HMC6343
• Manufacturer: Honeywell

Specifications of HMC6343

• Operating Temperature (min): -40C
• Operating Temperature Classification: Commercial
• Rad Hardened: No
• Lead Free Status / RoHS Status: Compliant

HMC6343
BASIC DEVICE OPERATION
The Honeywell HMC6343 magnetoresistive sensor circuit is a trio of magnetic sensors, accelerometers, and analog
support circuits to measure magnetic fields. Additionally a microcontroller is integrated for computation of direction and
calibration. With power supply applied, the sensor converts any incident magnetic field in the sensitive axis direction to a
differential voltage output. In addition to the bridge circuit, the sensors have on-chip magnetically coupled offset straps for
incident field adjustment.
The circuit is sensitive to power supply noise, and adding a 1.0 microfarad ceramic capacitor is recommended on the
positive supply to help reduce noise. Also careful layout practices should be enforced to keep high current traces (>10mA)
a few millimeters away from the sensors. Also, since the sensors are typically sensing the earth’s magnetic field direction,
avoid employing RF/EMI shields using ferrous metals or coatings.
BASIC SCHEMATIC INTERFACE
Offset Straps
The three offset straps have a spiral of metallization that couples in the sensor element’s sensitive axis. The straps will
handle currents to buck or boost fields through the ±4 gauss linear measurement range, but designers should note the
thermal heating on the die when doing so.
With most applications, the offset strap is not utilized and can be ignored. Designers can leave one or both strap
connections (Off- and Off+) open circuited, or ground one connection node.
Operational Modes
The HMC6343 has three operational modes; Sleep, Standby, and R un. Sleep mode is defined as having the analog
circuitry powered off, and has the lowest power consumption while power is applied to the VDD pins. Standby mode has
the HMC6343 fully powered, but with no measurements performed and the processor is waiting for commands to perform.
Run mode is fully engaged in continuous measurements at the set rate, and ready to receive further commands. The
operational mode settings are stored in EEPROM register 0x04, and shown further the HMC6343 protocol definition.
6
HMC6343
HMC6343
CS_CTRL
CS_CTRL
VDD3
VDD3
VDD2
VDD2
VDD1
VDD1
GND2
GND2
GND1
GND1
SCL
SCL
SDA
SDA
CS
CS
3
3
32
32
36
36
35
35
21
21
11
11
22
22
29
29
25
25
1uF
1uF
+3.3V
+3.3V
10k
10k
10k
10k
GND
GND
I2C_CLK
I2C_CLK
I2C_DATA
I2C_DATA
VDD
VDD
HOST
HOST
P
P
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