Updated August, 2006 PNI SEN-L Leaded Magneto-Inductive Sensor General Description Features PNI Corporation’s Magneto-Inductive (MI) sensors are based on patented technology that delivers breakthrough, cost-effective magnetic field sensing performance. These sensors change inductance by 100% over their field measurement range. This variable inductance property is used in a patented temperature and noise stabilized oscillator/counter circuit to detect field variations. The PNI ASIC is the recommended implementation of this patented circuit, and can be used with the Sen-L to construct a magnetometer with up to three axes. Advantages include low voltage and power, small size leaded package, large signal noise immunity under all conditions, and a large dynamic range. Resolution and field measurement range are software configurable for a variety of applications. The measurement is very stable over temperature and inherently free from offset drift. y Low power: draws < 500 µA at 3 VDC y Small size: 14 x 4 mm (length x diameter) y Large field measurement range: ±550 µT (±5.5 Gauss) y High resolution field measurement: 0.0055 µT (0.000055 Gauss) y Few external components: PNI ASIC with two resistors per sensor. y Leaded component for through hole mounting These advantages have made PNI Corporation’s MI sensors the choice for a wide variety of applications. Applications y Handheld battery-powered devices with built-in compass feature. y High performance magnetic field sensing. y High performance solid state navigation equipment for automotive, marine, and Aeronautic applications. y Direction finding features for any device where bearing or attitude indicators have value. y Magnetic object proximity sensing. Ordering Information Part # MOQ Package RoHS Compliant 10165P >1000 Each Yes 10165 1000 Bag Yes Table 1 PNI Corporation 133 Aviation Blvd., suite 101, Santa Rosa, CA 95403-1084 USA Phone: (707) 566-2260, Fax: (707) 566-2261, Web: www.pnicorp.com This page left intentionally blank -2- PNI SEN-L Specifications SPECIFICATIONS CAUTION: Stresses beyond those listed under Table 1 may cause permanent damage to the device. These are stress ratings only. Functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Table 2: Absolute Maximum Ratings Symbol Parameter Maximum VCOIL Voltage across coil 2.5 VDC VB Coil breakdown voltage 200 VDC IIN Input pin current 20 mA at 25 ºC TSTRG Storage temperature -55 ºC to 130 ºC Table 3: Sensor Characteristics Parameter Minimum a DC resistance at 25 ºC DC resistance versus temperature Inductance Q factor b c Maximum Typical 0.5%/ºC 0.4%/ºC 1.75 mH 5.25 mH 0.1 0.2 Operating Temperature -30 ºC 80 ºC Storage Temperature -55 ºC 130 ºC a. b. c. Determined with a DC source No DC bias, 100 kHz at 1 Vp-p, orthogonal to Earth’s magnetic field Measured with an LCR meter -3- PNI SEN-L Specifications Table 4: Sensor Characteristics with PNI ASIC Parameter Minimum Current (Measured at ASIC Vcc) 3 VDC, Rb = 100 5 VDC, Rb = 150 Maximum 0.5 mA RMS 0.5 mA RMS Typical 0.35 mA RMS 0.35 mA RMS a Field measurement range 3 VDC, Rb = 100 5 VDC, Rb = 150 –550 µT –550 µT 550 µT 550 µT b Gain 3 VDC, Rb = 100 5 VDC, Rb = 150 45 - 54 count/µT 29 - 37 count/µT Linearity (error from best fit straight line at ±100 µT) 1% Resolution 1/gain µT Frequency 3VDC, RB = 100 (Within free Earth’s magnetic field.) Operating Temperature (when used with PNI ASIC) 50 kHz 90 kHz -20 ºC 70 ºC a. b. Field measurement range is defined as the monotonic region of the output characteristic curve. Gain is defined defined as the change in the number of counts from the ASIC, when the period select is set to 512, per change in the magnetic field in µT. For situations requiring higher gain and less field measurement range, the gain and resolution can be increased by a factor of 2 by setting the ASIC period select to 1024. When setting higher period selects, be aware that the ASIC counter can overflow if the field is strong enough to drive the count beyond a signed 16-bit integer. Period select set to 1024 is the highest setting where it is impossible to overflow the counter For more information, see “PNI ASIC, 3-Axis Magneto-Inductive Sensor Driver and Controller with SPI Serial Interface” datasheet -4- PNI SEN-L Typical Operating Chracterisitics Typical Operating Characteristics: SEN-L (3 VDC; Rb = 100 Figure 1: Temperature Characteristics Figure 2: Linearity vs. Temperature -5- PNI SEN-L Typical Operating Characteristics Figure 3: Linearity vs. Temperature, normalized to Room Temperature (RMT) Output Counts is defined as the Period Select (PS) setting for the PNI ASIC. For more information, see “PNI ASIC, 3-Axis Magneto-Inductive Sensor Driver and Controller with SPI Serial Interface” datasheet. -6- PNI SEN-L Recommended Circuit Block Diagram Recommended Circuit Block Diagram Figure 4: Block Diagram Rb is dependent on the supply voltage: 5 VDC: Rb = 150 9'&5E -7- PNI SEN-L Package Information Package Information Figure 5: Outline Dimensions -8- PNI SEN-L Sensor Lead Bending Instructions Sensor Lead Bending Instructions Tools Required: y Needle Nose Pliers y Ohm Meter Procedure: 1. With the needle nose pliers, grip the sensor lead, next to the body of the sensor so that the pliers cover a minimum of 2m of the lead. The actual length is to be determined by the application, but will never be less than 2 mm. Refer to Figure 6. 2. Using your fingers, slowly bend the lead to 90º from the sensor while maintaining a hold on the lead with the pliers. 3. Repeat Step 1 and Step 2 on the other lead, being careful to keep the second lead parallel to the first. 4. After both leads have been bent take a resistance reading of the sensor. If the reading is between DQG WKHVHQVRULVVWLOORSHUDWLRQDO Figure 6: Sensor Lead Bending -9-