BU52040HFV-TR

Hall IC Series Bipolar Latch Hall IC BU52040HFV No.10045EBT05 ●Description BU52040 Hall Effect IC for wheel keys / trackballs is designed to detect a switch in magnetic field from N to S (or vice versa) and maintain its detection result on the output until the next switch. Output is pulled low for S-pole fields and high for N-pole fields. This IC is ideal for detecting the number of shaft rotations inside of a wheel key, trackball, or other similar applications. Using two ICs can also enable detection of rotation direction. ●Features 1) Ideally suited for wheel keys or trackballs 2) Micropower operation (small current consumption via intermittent operation method) 3) Ultra-small outline package 4) Supports 1.8 V supply voltage 5) High ESD resistance: 8kV (HBM) ●Applications Wheel keys (zero-contact selection dials), trackballs, and other interface applications. ●Product Lineup Product name BU52040HFV Supply voltage (V) 1.65～3.30 Operation point Hysteresis (mT) (mT) +/-3.0※ 6.0 Period (µs) 500 Supply current (AVG) (µA) 200 Output type CMOS Package HVSOF5 ※Plus is expressed on the S-pole; minus on the N-pole ●Absolute Maximum Ratings BU52040HFV (Ta = 25°C) Parameters Power Supply Voltage Output Current Power dissipation Operating Temperature Range Storage Temperature Range Symbol VDD IOUT Pd Topr Tstg Limit -0.1～4.5 ± 0.5 536※2 -40～+85 -40～+125 ※1 Unit V mA mW °C °C ※1. Not to exceed Pd ※2. Reduced by 5.36mW for each increase in Ta of 1℃ over 25℃(mounted on 70mm×70 mm×1.6mm Glass-epoxy PCB) www.rohm.com © 2010 ROHM Co., Ltd. All rights reserved. 1/12 2010.01 - Rev.B BU52040HFV ●Magnetic, Electrical Characteristics BU52040HFV (Unless otherwise specified, VDD=1.80V, Ta=25°C) Limit Parameters Symbol Min Typ Power Supply Voltage Operation point Release Point Hysteresis Period Output High Volｔage Output Low Voltage Supply Current 1 Supply Current During Startup Time 1 Supply Current During Standby Time 1 Supply Current 2 Supply Current During Startup Time 2 Supply Current During Standby Time 2 VDD Bop Brp Bhys Tp VOH VOL IDD1(AVG) IDD1(EN) IDD1(DIS) IDD2(AVG) IDD2(EN) IDD2(DIS) 1.65 1.0 -5.0 VDD - 0.2 1.80 3.0 -3.0 6.0 500 200 3.0 2.0 300 4.5 3.5 Technical Note Max 3.30 5.0 -1.0 1200 0.2 300 450 - Unit V mT mT mT µs V V µA mA µA µA mA µA Conditions B < Brp※3 IOUT =-0.5mA Bop < B※ IOUT =+0.5mA VDD =1.8V, Average VDD =1.8V, During Startup Time Value VDD =1.8V, During Standby Time Value VDD=2.7V, Average VDD=2.7V, During Startup Time Value VDD=2.7V, During Standby Time Value 3 ※3. B = Magnetic flux density 1mT=10Gauss Positive (“+”) polarity flux is defined as the magnetic flux from south pole which is direct toward to the branded face of the sensor. After applying power supply, it takes one cycle of period (TP) to become definite output. Radiation hardiness is not designed. www.rohm.com © 2010 ROHM Co., Ltd. All rights reserved. 2/12 2010.01 - Rev.B BU52040HFV ●Figure of measurement circuit Bop/Brp Tp 200Ω Technical Note VDD VDD 100μF GND OUT V VDD VDD Oscilloscope GND OUT Bop and Brp are measured with applying the magnetic field from the outside. The period is monitored by Oscilloscope. Fig.1 Bop,Brp measurement circuit Fig.2 Tp measurement circuit VOH VDD VDD 100μF GND OUT V IOUT＝0.5mA Fig.3 VOH measurement circuit VOL VDD VDD 100μF GND OUT V IOUT＝0.5mA Fig.4 VOL measurement circuit IDD A VDD OUT GND VDD 2200μF Fig.5 IDD measurement circuit www.rohm.com © 2010 ROHM Co., Ltd. All rights reserved. 3/12 2010.01 - Rev.B BU52040HFV ●Reference Data 8.0 MAGNETIC FLUX DENSITY [mT] 6.0 4.0 2.0 0.0 -2.0 -4.0 -6.0 - 8.0 -60 -40 -20 0 20 40 60 80 100 8.0 MAGNETIC FLUX DENSITY [mT] 800 Technical Note VDD=1.8V 6.0 4.0 2.0 0.0 -2.0 -4.0 -6.0 - 8.0 1.4 Bop Ta = 25°C Bop PERIOD [ μs] 700 600 500 400 300 200 VDD=1.8V Brp Brp 1.8 2.2 2.6 3.0 3.4 3.8 -60 -40 -20 0 20 40 60 80 100 AMBIENT TEMPERATURE [℃] SUPPLY VOLTAGE ［ V ］ AMBIENT TEMPERATURE [℃] Fig.6 Bop,Brp– Ambient temperature Fig.7 Bop,Brp– Supply voltage Fig.8 TP– Ambient temperature AVERAGE SUPPLY CURRENT [µA] AVERAGE SUPPLY CURRENT [µA] 800 700 PERIOD [ μs] 400 350 300 250 200 150 100 -60 -40 -20 0 20 40 60 80 100 AMBIENT TEMPERATURE [℃] VDD=1.8V 400 350 300 250 200 150 100 1.4 1.8 2.2 2.6 3.0 3.4 3.8 SUPPLY VOLTAGE [V] Ta = 25°C Ta = 25°C 600 500 400 300 200 1.4 1.8 2.2 2.6 3.0 3.4 3.8 SUPPLY VOLT AGE [V] Fig.9 TP– Supply voltage ●Block Diagram BU52040HFV ＶDD Fig.10 IDD– Ambient temperature Fig.11 IDD – Supply voltage 0.1 µF 4 TIMING LOGIC DYNAMIC OFFSET CANCELLATION HALL ELEMENT Adjust the bypass capacitor value as necessary, according to voltage noise conditions, etc. SAMPLE & HOLD × 5 OUT The CMOS output terminals enable direct connection to the PC, with no external pull-up resistor required. LATCH 2 GND Fig.12 PIN No. 1 2 3 4 5 PIN NAME N.C. GND N.C. VDD OUT POWER SUPPLY OUTPUT GROUND OPEN or Short to GND. FUNCTION COMMENT OPEN or Short to GND. 5 4 4 5 1 2 3 3 Surface 2 1 Reverse www.rohm.com © 2010 ROHM Co., Ltd. All rights reserved. 4/12 2010.01 - Rev.B BU52040HFV Technical Note ●Description of Operations (Micro-power Operation) The Hall Effect IC for wheel keys / trackballs adopts an intermittent operation method to save energy. At startup, the Hall elements, amp, comparator and other detection circuits power ON and magnetic detection begins. During standby, the detection circuits power OFF, thereby reducing current consumption. The detection results are held while standby is active, and then output. Reference period: 500 µs (MAX. 1200 µs) Reference startup time: 24 µs IDD Period Startup time Standby t Fig.13 (Offset Cancellation) The Hall elements form an equivalent Wheatstone (resistor) bridge circuit. Offset voltage may be generated by a differential in this bridge resistance, or can arise from changes in resistance due to package or bonding stress. A dynamic offset cancellation circuit is employed to cancel this offset voltage. When Hall elements are connected as shown in Fig. 14 and a magnetic field is applied perpendicularly to the Hall elements, voltage is generated at the mid-point terminal of the bridge. This is known as the Hall voltage. Dynamic cancellation switches the wiring (shown in the figure) to redirect the current flow to a 90˚ angle from its original path, and thereby cancels the Hall voltage. The magnetic signal (only) is maintained in the sample/hold circuit during the offset cancellation process and then released. VDD I B× ＋ Hall Voltage － GND Fig.14 www.rohm.com © 2010 ROHM Co., Ltd. All rights reserved. 5/12 2010.01 - Rev.B BU52040HFV (Magnetic Field Detection Mechanism) OUT [V] Technical Note High Low Brp N-pole 0 B Bop S-pole Magnetic flux density [mT] Fig.15 The IC detects magnetic fields that running horizontal to the top layer of the package. When the magnetic pole switches from N to S, the output changes from high to low; likewise, when the magnetic pole switches from S to N, the output changes from low to high. The output condition is held unit the next switch in magnetic polarity is detected. [Operation in Continuously Changing Magnetic Fields] Direction of magnet movement S Magnet S N N S S N N S S N N Hall IC S Magnetic field N Bop Brp High Hall IC output Low Fig.16 The IC can detect a continuous switch in magnetic field (from N to S and S to N) as depicted above. www.rohm.com © 2010 ROHM Co., Ltd. All rights reserved. 6/12 2010.01 - Rev.B BU52040HFV ●Intermittent Operation at Power ON Technical Note VDD Supply current (Intermittent operation) Startup time Standby time Startup time Standby time OUT (N magnetic field present) Indefinite High (B