HMC5843 Honeywell Microelectronics & Precision Sensors, HMC5843 Datasheet

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... HMC5843 include Consumer Electronics, Auto Navigation Systems, Personal Navigation Devices, and Magnetometers. The HMC5843 utilizes Honeywell’s Anisotropic Magnetoresistive (AMR) technology that provides advantages over other magnetic sensor technologies. The sensors feature precision in-axis sensitivity and linearity, solid-state construction with very low cross-axis sensitivity designed to measure both direction and magnitude of Earth’s magnetic fields, from tens of micro-gauss to 6 gauss. Honeywell’ ...

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... HMC5843 SPECIFICATIONS Characteristics Power Supply Supply Voltage Current Draw ASIC Only – Sleep Mode (dual supplies) ASIC Only – Idle Mode (dual supplies) ASIC and Sensors – Measurement Mode (dual supplies, default register modes) AVDD = 3.3 volts, DVDD = 1.98 volts Magnetic Sensors ...

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... Voltage Regulator Enable, (GND = Dual Supply, AVDD = Single Supply) Analog Supply Ground/Return Analog Positive Supply Data Ready – Test Point Serial Data – I2C Master/Slave Data Table 1: Pin Configurations HMC5843 – bottom view HMC5843 – bottom view OFFP OFFP 7 7 OFFN OFFN SETP SETP 10 10 SETN SETN ...

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... The following is the recommend printed circuit board (PCB) footprint for the HMC5843. PCB Pad Definition and Traces The HMC5843 is a fine pitch LCC package with a 0.50mm pin pitch (spacing), with the pin pads defined as 0.40mm by 0.25mm in size. PCB pads are recommended to be oversized by 0.025mm from each pad for a short dimension oversize of 0 ...

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... HMC5843 INTERNAL SCHEMATIC DIAGRAM HMC5843 HMC1043 AMR AMR AMR OFFSET SET/RESET SETP C2 0.22 µF SINGLE SUPPLY REFERENCE DESIGN HMC5843 2 I www.honeywell.com HMC5843 ASIC SVDD TEST AGND AMP BIAS CURRENT BP BN H-BRIDGE SETN SETC 15 DVDD NC +2.5V to 3.3V 16 VREN 18 AVDD 2 SDAP 3 SCLP 1 SCL ...

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... BASIC DEVICE OPERATION Anisotropic Magneto-Resistive Sensors The Honeywell HMC5843 magnetoresistive sensor circuit is a trio of sensors and application specific support circuits to measure magnetic fields. With power supply applied, the sensor converts any incident magnetic field in the sensitive axis directions to a differential voltage output. The magnetoresistive sensors are made of a nickel-iron (Permalloy) thin-film deposited on a silicon wafer and patterned as a resistive strip element ...

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... AGND this devices operates with both AVDD and DVDD as supplies. The table below shows the modes available at the various power supply conditions. DVDD AVDD High High High Low Internally High regulated Low Low HMC5843 HMC5843 www.honeywell.com Pin Modes Description VREN Supported AGND All, except Internal voltage regulator: Disabled. ...

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... HMC5843 ASIC Turn-On Times The table below shows the turn-on time for individual functions within this ASIC. Parameter Sym. Clock Turn-on t Logic Turn-on t Analog Turn-on t Voltage Regulator Turn Voltage Regulator This ASIC has an internal voltage regulator which, depending on the application needs, may be used instead of supplying voltage to pin DVDD ...

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... HMC5843 Charge Current Limit The current that reservoir capacitor (C1) can draw when charging is limited. When using dual supplies this device shall limit the current drawn from DVDD source to charge this capacitor. When only a single supply is used, Pin DVDD is externally tied to pin C1. In this configuration, current is still limited. For example, the internal voltage regulator will limit this current draw ...

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... HMC5843 MAGNETIC MEASUREMENTS The measurement type is set by bits MS[n] in the configuration registers. There are two main configurations, normal measurement and bias measurement, where the self-test bias measurement can be a positive or a negative bias current on the offset strap to emulate an external magnetic field. The gain, GN[n]; the delay, DL[n]; and the data output rate, DO[n] settings are common to all measurement configurations. In the normal measurement process, the sensor’ ...

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... HMC5843 The timing diagram for the normal measurement is shown below. “Normal Meas” defines the timing of the Normal Measurement Flow Diagram below. When the device is in continuous-measurement mode, the time shown as “Idle” defines time the device is in low current state, similar to idle mode. When the device is in single-measurement mode, the time shown as “ ...

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... HMC5843 Self-Test Bias Measurement The self-test bias measurement flow is shown in the diagram below. Device in idle mode. Wait for MD[n]=0b00 or MD[n]=0b01 devices: (SVDD, Amp, Wait. Sensor turn-on Meas1: Measure all 3 Apply bias current to Wait. Sensor turn-on The timing diagram for both the bias measurement is shown below. “Bias Meas” defines the timing of figure below. When the device is in continuous-measurement mode, the time shown as “ ...

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... HMC5843 REGISTERS This device is controlled and configured via a number of on-chip registers, which are described in this section. In the following descriptions, set implies a logic 1, and reset or clear implies a logic 0, unless stated otherwise. Register List The table below lists the registers and their access. All address locations are 8 bits. ...

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... HMC5843 Register Access This section describes the process of reading from and writing to this device. The devices uses an address pointer to indicate which register location read from or written to. These pointer locations are sent from the master to this slave device and succeed the 7-bit address plus 1 bit read/write identifier. ...

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... HMC5843 MS1 MS0 Mode Normal measurement configuration (default). In normal measurement 0 0 configuration the device follows normal measurement flow. Pins BP and BN are left floating and high impedance. Positive bias configuration. In positive bias configuration, a positive current forced across the resistive load on pins BP and BN. ...

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... HMC5843 The table below shows nominal gain settings. GN2 GN1 GN0 The table below shows nominal delay times settings. These values may have up to ±50% variation due to PVT. DL3 DL2 Sensor Input Field Output Range Range: Not Recommended Not Recommended Not Recommended Not Recommended 0xF800– ...

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... HMC5843 Mode Register The mode register is an 8-bit register from which data can be read or to which data can be written. This register is used to select the operating mode of the device. MR0 through MR7 indicate bit locations, with MR denoting the bits that are in the mode register ...

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... HMC5843 DXRA7 DXRA6 (0) (0) DXRB7 DXRB6 (0) (0) Data Output Y Registers A and B The data output Y registers are two 8 -bit registers, data output register A and data output register B. These registers store the measurement result from channel Y. Data output Y register A contains the MSB from the measurement result, and data output Y register B contains the LSB from the measurement result. The value stored in these two registers is a 16-bit value in 2’ ...

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... HMC5843 Data Output Register Operation When one or more of the output registers are read, new data cannot be placed in any of the output data registers until all six data output registers are read. This requirement also impacts DRDY and RDY, which cannot be cleared until new data is placed in all the output registers ...

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... I C COMMUNICATION PROTOCOL The HMC5843 communicates via a two-wire I2C bus system as a slave device. The HMC5843 uses a simple protocol with the interface protocol defined by the I2C bus specification, and by this document. The data rate is at the standard- mode 100kbps or 400kbps rates as defined in the I2C Bus Specifications. The bus bit format -bit Data/Address send and a 1 -bit acknowledge bit. The format of the data bytes (payload) shall be case sensitive ASCII characters or binary data to the HMC5843 slave, and binary data returned. Negative binary values will be in two’ ...

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... OPERATIONAL EXAMPLES The HMC5843 has a fairly quick stabilization time from no voltage to stable and ready for data retrieval. The nominal 5 milli-seconds with the factory default single measurement mode means that the six Bytes of magnetic data registers (DXRA, DXRB, DYRA, DYRB, DZRA, and DZRB) are filled with a valid first measurement ...