{"product_id":"us1881-bipolar-hall-effect-latch","title":"US1881 Bipolar Hall Effect Latch Sensor – TO-92, 3.5V–24V","description":"\u003cstyle\u003e\n.nznpd{--o:#F57C00;--od:#E65100;--ink:#0F172A;--mut:#5b6573;--line:#E8ECF0;--soft:#F7F8FA;max-width:1120px;margin:0 auto;color:var(--ink);font-family:inherit;line-height:1.6}\n.nznpd,.nznpd *{box-sizing:border-box}\n.nznpd p{margin:0;color:var(--mut);font-size:15px;line-height:1.65}\n.nznpd strong{color:var(--ink)}\n.nznpd__intro{font-size:16px;color:var(--ink);font-weight:500;line-height:1.6;max-width:72ch}\n.nznpd__checks{list-style:none;padding:0;margin:22px 0 0;display:grid;grid-template-columns:repeat(2,1fr);column-gap:26px;row-gap:13px}\n.nznpd__checks li{display:flex;gap:11px;align-items:flex-start;font-size:15px;color:var(--ink);line-height:1.45}\n.nznpd__checks li::before{content:\"\\2713\";flex:0 0 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class=\"nznpd__lead\"\u003e\n\u003cp class=\"nznpd__intro\"\u003eThe US1881 is a bipolar Hall effect latch IC fabricated from mixed-signal CMOS technology with advanced chopper stabilisation for accurate, stable magnetic switch points. Unlike a simple unipolar switch, it latches its output and holds state when the magnet is removed — making it the go-to choice for BLDC motor commutation, angular position sensing, and non-contact toggle switching across a wide 3.5V–24V supply range.\u003c\/p\u003e\n\u003cbr\u003e\n\u003cul class=\"nznpd__checks\"\u003e\n\u003cli\u003eBipolar latch — south pole sets output ON (BOP), north pole sets output OFF (BRP)\u003c\/li\u003e\n\u003cli\u003e3.5V–24V supply range, up to 50 mA output current\u003c\/li\u003e\n\u003cli\u003eChopper-stabilised amplifier — stable thresholds across temperature\u003c\/li\u003e\n\u003cli\u003eMixed-signal CMOS — optimised for 5V and 12V BLDC motor commutation\u003c\/li\u003e\n\u003cli\u003eSOT-23 package (output polarity reversed vs UA package)\u003c\/li\u003e\n\u003cli\u003e−40°C to +150°C operating temperature range\u003c\/li\u003e\n\u003cli\u003e100 mW max power dissipation, RoHS compliant\u003c\/li\u003e\n\u003cli\u003eCompatible with Arduino, ESP32, Raspberry Pi and more\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\n\u003csection class=\"nznpd__block\"\u003e\n\u003ch3 class=\"nznpd__h\"\u003eSpecifications\u003c\/h3\u003e\n\u003cbr\u003e\n\u003cdiv class=\"nznpd__specs\"\u003e\n\u003cdiv class=\"nznpd__spec\"\u003e\n\u003cspan\u003eModel\u003c\/span\u003e\u003cstrong\u003eUS1881\u003c\/strong\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"nznpd__spec\"\u003e\n\u003cspan\u003eTechnology\u003c\/span\u003e\u003cstrong\u003eMixed-Signal CMOS, Chopper-Stabilised\u003c\/strong\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"nznpd__spec\"\u003e\n\u003cspan\u003eSupply Voltage (Vdd)\u003c\/span\u003e\u003cstrong\u003e3.5V – 24V DC\u003c\/strong\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"nznpd__spec\"\u003e\n\u003cspan\u003eSupply Current (IDD)\u003c\/span\u003e\u003cstrong\u003e50 mA max\u003c\/strong\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"nznpd__spec\"\u003e\n\u003cspan\u003eOutput Voltage (VOUT)\u003c\/span\u003e\u003cstrong\u003e3.5V – 24V\u003c\/strong\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"nznpd__spec\"\u003e\n\u003cspan\u003eOutput Current (IOUT)\u003c\/span\u003e\u003cstrong\u003e50 mA max\u003c\/strong\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"nznpd__spec\"\u003e\n\u003cspan\u003ePower Dissipation (PD)\u003c\/span\u003e\u003cstrong\u003e100 mW max\u003c\/strong\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"nznpd__spec\"\u003e\n\u003cspan\u003eOperating Temperature (Ta)\u003c\/span\u003e\u003cstrong\u003e−40°C to +150°C\u003c\/strong\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"nznpd__spec\"\u003e\n\u003cspan\u003eOutput Type\u003c\/span\u003e\u003cstrong\u003eOpen-drain latch (BOP on, BRP off)\u003c\/strong\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"nznpd__spec\"\u003e\n\u003cspan\u003eSwitch Behaviour\u003c\/span\u003e\u003cstrong\u003eBipolar latch — south pole = ON, north pole = OFF, no magnet = holds state\u003c\/strong\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"nznpd__spec\"\u003e\n\u003cspan\u003ePackage\u003c\/span\u003e\u003cstrong\u003eSOT-23 \/ TO-92 (UA) — 3-pin, RoHS compliant\u003c\/strong\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"nznpd__spec\"\u003e\n\u003cspan\u003eMCU Compatibility\u003c\/span\u003e\u003cstrong\u003eArduino, ESP32, Raspberry Pi, STM32, PIC\u003c\/strong\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/section\u003e\n\n\u003csection class=\"nznpd__block\"\u003e\n\u003ch3 class=\"nznpd__h\"\u003eWhat’s in the pack\u003c\/h3\u003e\n\u003cbr\u003e\n\u003cdiv class=\"nznpd__included\"\u003e\n\u003cdiv class=\"nznpd__qty\"\u003e×\u003c\/div\u003e\n\u003cdiv\u003e\n\u003cstrong\u003eUS1881 Bipolar Hall Effect Latch ICs\u003c\/strong\u003e\n\u003cp\u003eQuantity as selected. TO-92 flat (UA) package, through-hole, ready to use.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/section\u003e\n\n\u003csection class=\"nznpd__block\"\u003e\n\u003ch3 class=\"nznpd__h\"\u003eGreat for\u003c\/h3\u003e\n\u003cbr\u003e\n\u003cdiv class=\"nznpd__uses\"\u003e\n\u003cdiv class=\"nznpd__use\"\u003eBLDC motor commutation in drones, e-bikes and power tools\u003c\/div\u003e\n\u003cdiv class=\"nznpd__use\"\u003eSolid state and non-contact toggle switching\u003c\/div\u003e\n\u003cdiv class=\"nznpd__use\"\u003eSpeed and RPM sensing with multi-pole ring magnets\u003c\/div\u003e\n\u003cdiv class=\"nznpd__use\"\u003eAngular and linear position sensing\u003c\/div\u003e\n\u003cdiv class=\"nznpd__use\"\u003eCurrent sensing applications\u003c\/div\u003e\n\u003cdiv class=\"nznpd__use\"\u003eProximity and presence detection in harsh environments\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/section\u003e\n\n\u003csection class=\"nznpd__block\"\u003e\n\u003cdiv class=\"nznpd__qs\"\u003e\n\u003ch3\u003eGetting started\u003c\/h3\u003e\n\u003col class=\"nznpd__steps\"\u003e\n\u003cli\u003e\u003cdiv\u003e\n\u003cstrong\u003eOrient the sensor\u003c\/strong\u003e\u003cp\u003eHold the TO-92 (UA) package with the flat branded face toward you, legs pointing down. Pins 1, 2, 3 run left to right. The flat face is the active sensing surface.\u003c\/p\u003e\n\u003c\/div\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cdiv\u003e\n\u003cstrong\u003eWire power and ground\u003c\/strong\u003e\u003cp\u003eConnect Pin 1 (VDD) to your supply — 5V for Arduino, or use 5V Vin on ESP32 for adequate headroom above the 3.5V minimum. Connect Pin 2 to GND. Add a 100 nF bypass capacitor between VDD and GND close to the sensor.\u003c\/p\u003e\n\u003c\/div\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cdiv\u003e\n\u003cstrong\u003eConnect the output with a pull-up\u003c\/strong\u003e\u003cp\u003eConnect Pin 3 (OUT) to a digital GPIO. Use \u003ccode\u003epinMode(pin, INPUT_PULLUP)\u003c\/code\u003e in Arduino, or add a 10 kΩ resistor from Pin 3 to VDD.\u003c\/p\u003e\n\u003c\/div\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cdiv\u003e\n\u003cstrong\u003eTest the latch behaviour\u003c\/strong\u003e\u003cp\u003ePower-up state is undefined. Sweep a known magnetic pole past the sensor at startup to establish a known state. South pole facing the marked face = output ON. North pole = output OFF. Remove the magnet and the output holds its last state.\u003c\/p\u003e\n\u003c\/div\u003e\u003c\/li\u003e\n\u003c\/ol\u003e\n\u003c\/div\u003e\n\u003c\/section\u003e\n\n\u003csection class=\"nznpd__block\"\u003e\n\u003ch3 class=\"nznpd__h\"\u003eHow it works\u003c\/h3\u003e\n\u003cdiv class=\"nzndemo\"\u003e\n  \u003cdiv class=\"nzndemo__layout\"\u003e\n    \u003cdiv\u003e\n      \u003cdiv class=\"nzndemo__canvas\"\u003e\n        \u003csvg id=\"nznd-svg\" viewbox=\"0 0 400 210\" width=\"100%\" style=\"max-width:420px;overflow:visible\"\u003e\n          \u003cg id=\"nznd-mag\" transform=\"translate(8,62)\"\u003e\n            \u003crect id=\"nznd-left-rect\" x=\"0\" y=\"0\" width=\"56\" height=\"72\" rx=\"5\" fill=\"#DDEEFF\" stroke=\"#5B9BD5\" stroke-width=\"1.5\"\u003e\u003c\/rect\u003e\n            \u003ctext id=\"nznd-left-lbl\" x=\"28\" y=\"43\" text-anchor=\"middle\" font-size=\"20\" font-weight=\"700\" fill=\"#1a4a7a\"\u003eS\u003c\/text\u003e\n            \u003crect id=\"nznd-right-rect\" x=\"56\" y=\"0\" width=\"56\" height=\"72\" rx=\"5\" fill=\"#FDDDD9\" stroke=\"#E05C45\" stroke-width=\"1.5\"\u003e\u003c\/rect\u003e\n            \u003ctext id=\"nznd-right-lbl\" x=\"84\" y=\"43\" text-anchor=\"middle\" font-size=\"20\" font-weight=\"700\" fill=\"#7a1a0a\"\u003eN\u003c\/text\u003e\n            \u003ctext x=\"56\" y=\"90\" text-anchor=\"middle\" font-size=\"11\" fill=\"#5b6573\"\u003emagnet\u003c\/text\u003e\n          \u003c\/g\u003e\n          \u003cg id=\"nznd-lines\" opacity=\"0\"\u003e\n            \u003cline x1=\"130\" y1=\"84\" x2=\"182\" y2=\"98\" stroke=\"#5B9BD5\" stroke-width=\"1\" stroke-dasharray=\"4,3\"\u003e\u003c\/line\u003e\n            \u003cline x1=\"130\" y1=\"98\" x2=\"182\" y2=\"98\" stroke=\"#5B9BD5\" stroke-width=\"1\" stroke-dasharray=\"4,3\"\u003e\u003c\/line\u003e\n            \u003cline x1=\"130\" y1=\"112\" x2=\"182\" y2=\"98\" stroke=\"#5B9BD5\" stroke-width=\"1\" stroke-dasharray=\"4,3\"\u003e\u003c\/line\u003e\n            \u003cpolygon id=\"nznd-arr1\" points=\"182,93 192,98 182,103\" fill=\"#5B9BD5\"\u003e\u003c\/polygon\u003e\n          \u003c\/g\u003e\n          \u003cg id=\"nznd-sensor\" transform=\"translate(192,46)\"\u003e\n            \u003crect x=\"0\" y=\"0\" width=\"96\" height=\"90\" rx=\"5\" fill=\"#fff\" stroke=\"#CBD5E0\" stroke-width=\"1.5\"\u003e\u003c\/rect\u003e\n            \u003crect x=\"0\" y=\"0\" width=\"6\" height=\"90\" rx=\"2\" fill=\"#F0F4F8\"\u003e\u003c\/rect\u003e\n            \u003ctext x=\"51\" y=\"30\" text-anchor=\"middle\" font-size=\"11\" font-weight=\"700\" fill=\"#0F172A\"\u003eUS1881\u003c\/text\u003e\n            \u003ctext x=\"51\" y=\"50\" text-anchor=\"middle\" font-size=\"10\" fill=\"#5b6573\"\u003eflat face\u003c\/text\u003e\n            \u003cline x1=\"20\" y1=\"90\" x2=\"20\" y2=\"118\" stroke=\"#0F172A\" stroke-width=\"2\"\u003e\u003c\/line\u003e\n            \u003cline x1=\"48\" y1=\"90\" x2=\"48\" y2=\"118\" stroke=\"#0F172A\" stroke-width=\"2\"\u003e\u003c\/line\u003e\n            \u003cline x1=\"76\" y1=\"90\" x2=\"76\" y2=\"118\" stroke=\"#0F172A\" stroke-width=\"2\"\u003e\u003c\/line\u003e\n            \u003ctext x=\"20\" y=\"134\" text-anchor=\"middle\" font-size=\"10\" fill=\"#5b6573\"\u003eVDD\u003c\/text\u003e\n            \u003ctext x=\"48\" y=\"134\" text-anchor=\"middle\" font-size=\"10\" fill=\"#5b6573\"\u003eGND\u003c\/text\u003e\n            \u003ctext x=\"76\" y=\"134\" text-anchor=\"middle\" font-size=\"10\" fill=\"#5b6573\"\u003eOUT\u003c\/text\u003e\n          \u003c\/g\u003e\n          \u003cline x1=\"288\" y1=\"98\" x2=\"322\" y2=\"98\" stroke=\"#CBD5E0\" stroke-width=\"1.5\"\u003e\u003c\/line\u003e\n          \u003ccircle id=\"nznd-led\" cx=\"338\" cy=\"98\" r=\"14\" fill=\"#F7F8FA\" stroke=\"#CBD5E0\" stroke-width=\"1.5\"\u003e\u003c\/circle\u003e\n          \u003ctext id=\"nznd-ledlbl\" x=\"338\" y=\"79\" text-anchor=\"middle\" font-size=\"11\" font-weight=\"700\" fill=\"#5b6573\"\u003e?\u003c\/text\u003e\n          \u003ctext x=\"338\" y=\"122\" text-anchor=\"middle\" font-size=\"10\" fill=\"#5b6573\"\u003eLED\u003c\/text\u003e\n        \u003c\/svg\u003e\n      \u003c\/div\u003e\n    \u003c\/div\u003e\n    \u003cdiv class=\"nzndemo__controls\"\u003e\n      \u003cdiv\u003e\n        \u003cdiv class=\"nzndemo__label\"\u003eApply magnetic field\u003c\/div\u003e\n        \u003cdiv class=\"nzndemo__btns\"\u003e\n          \u003cbutton class=\"nzndemo__btn\" id=\"nznd-bs\" onclick=\"nzndApply('south')\"\u003eSouth pole\u003cbr\u003efacing sensor\u003c\/button\u003e\n          \u003cbutton class=\"nzndemo__btn\" id=\"nznd-bn\" onclick=\"nzndApply('north')\"\u003eNorth pole\u003cbr\u003efacing sensor\u003c\/button\u003e\n          \u003cbutton class=\"nzndemo__btn nzndemo__btn-full\" id=\"nznd-br\" onclick=\"nzndApply('none')\"\u003eRemove magnet\u003c\/button\u003e\n        \u003c\/div\u003e\n      \u003c\/div\u003e\n      \u003cdiv class=\"nzndemo__status\"\u003e\n        \u003cdiv class=\"nzndemo__label\" style=\"margin-bottom:2px\"\u003eOutput state\u003c\/div\u003e\n        \u003cdiv class=\"nzndemo__row\"\u003e\n\u003cspan class=\"nzndemo__rowkey\"\u003ePin 3 (OUT)\u003c\/span\u003e\u003cspan class=\"nzndemo__rowval\" id=\"nznd-pin\"\u003e—\u003c\/span\u003e\n\u003c\/div\u003e\n        \u003cdiv class=\"nzndemo__row\"\u003e\n\u003cspan class=\"nzndemo__rowkey\"\u003eLatch\u003c\/span\u003e\u003cspan class=\"nzndemo__badge\" id=\"nznd-badge\"\u003eundefined\u003c\/span\u003e\n\u003c\/div\u003e\n        \u003cdiv class=\"nzndemo__row\"\u003e\n\u003cspan class=\"nzndemo__rowkey\"\u003eMagnet\u003c\/span\u003e\u003cspan class=\"nzndemo__rowval\" id=\"nznd-mag-lbl\"\u003enone\u003c\/span\u003e\n\u003c\/div\u003e\n      \u003c\/div\u003e\n      \u003cdiv class=\"nzndemo__info\"\u003e\n        \u003cdiv class=\"nzndemo__info-title\" id=\"nznd-ititle\"\u003ePower-up state\u003c\/div\u003e\n        \u003cdiv class=\"nzndemo__info-body\" id=\"nznd-ibody\"\u003eOutput is undefined at power-up. Apply a pole to the flat face to establish a known state.\u003c\/div\u003e\n      \u003c\/div\u003e\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"nzndemo__concepts\"\u003e\n    \u003cdiv class=\"nzndemo__concept\"\u003e\n      \u003cdiv class=\"nzndemo__concept-title\"\u003eBOP — operate point\u003c\/div\u003e\n      \u003cdiv class=\"nzndemo__concept-body\"\u003eSouth pole exceeds the threshold. Output latches LOW (on). Holds after magnet is removed.\u003c\/div\u003e\n    \u003c\/div\u003e\n    \u003cdiv class=\"nzndemo__concept\"\u003e\n      \u003cdiv class=\"nzndemo__concept-title\"\u003eBRP — release point\u003c\/div\u003e\n      \u003cdiv class=\"nzndemo__concept-body\"\u003eNorth pole exceeds the threshold. Output latches HIGH (off). Holds after magnet is removed.\u003c\/div\u003e\n    \u003c\/div\u003e\n    \u003cdiv class=\"nzndemo__concept\"\u003e\n      \u003cdiv class=\"nzndemo__concept-title\"\u003eMagnetic memory\u003c\/div\u003e\n      \u003cdiv class=\"nzndemo__concept-body\"\u003eNo continuous field needed — the latch retains its state indefinitely until the opposite pole is applied.\u003c\/div\u003e\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"nzndemo__vs\"\u003e\n\u003cstrong\u003eBipolar latch vs unipolar switch:\u003c\/strong\u003e A unipolar switch (e.g. OH137) only responds to one pole and resets when the magnet is removed. The US1881 needs both poles — south to turn on, north to turn off — and holds state when the magnet is gone. Ideal for motor commutation and toggle switching.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/section\u003e\n\n\u003csection class=\"nznpd__block\"\u003e\n\u003ch3 class=\"nznpd__h\"\u003eCommon questions\u003c\/h3\u003e\n\u003cbr\u003e\n\u003cdiv class=\"nznpd__faqs\"\u003e\n\u003cdetails class=\"nznpd__faq\" open\u003e\n\u003csummary\u003eWhat is the difference between bipolar latch and unipolar switch?\u003c\/summary\u003e\n\u003cp\u003eA unipolar switch only responds to one pole (usually south). A bipolar latch responds to both — south sets the output ON, north sets it OFF, and removing the magnet holds the last state. This makes the US1881 ideal for motor commutation and toggle applications where you need definite on\/off control from alternating poles.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails class=\"nznpd__faq\"\u003e\n\u003csummary\u003eDoes the output hold state when the magnet is removed?\u003c\/summary\u003e\n\u003cp\u003eYes. This is the key feature of a latch. Once set by a magnetic field, the US1881 holds its output until the opposite pole is applied. Power-up state is undefined, so your firmware should detect pole position at startup to establish a known state.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails class=\"nznpd__faq\"\u003e\n\u003csummary\u003eIs the SOT-23 package the same polarity as the TO-92 (UA)?\u003c\/summary\u003e\n\u003cp\u003eNo — the SOT-23 output polarity is reversed relative to the UA (TO-92 flat) package. Always check your package marking. For the UA package: south pole facing the flat face = output ON (low). For SOT-23 it is the opposite.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails class=\"nznpd__faq\"\u003e\n\u003csummary\u003eWhat supply voltage does it need?\u003c\/summary\u003e\n\u003cp\u003eThe US1881 operates from 3.5V to 24V, making it compatible with 5V Arduino systems and 12V motor driver circuits alike. The output voltage mirrors the supply range (3.5V–24V), and maximum output current is 50 mA.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails class=\"nznpd__faq\"\u003e\n\u003csummary\u003eDo I need a pull-up resistor on the output?\u003c\/summary\u003e\n\u003cp\u003eYes. The output is open-drain, so it needs a pull-up to VDD to read a HIGH state. A 10 kΩ resistor works well, or use \u003ccode\u003eINPUT_PULLUP\u003c\/code\u003e mode on an Arduino GPIO to use the internal pull-up.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003c\/div\u003e\n\u003c\/section\u003e\n\n\u003cp class=\"nznpd__note\"\u003e\u003cstrong\u003ePackage note:\u003c\/strong\u003e The US1881 UA (TO-92 flat) and SOT-23 packages have reversed output polarity — always verify your package type before wiring. For a simpler south-pole-only switch, see the OH137 unipolar Hall switch.\u003c\/p\u003e\n\u003c\/div\u003e\n\n\u003cscript\u003e\n(function(){\nvar state={pole:'none',latch:'unknown'};\nvar msgs={\n  south:{t:'South pole applied — BOP triggered',b:'South pole field exceeds the \u003cstrong\u003eBurst Operate Point (BOP)\u003c\/strong\u003e. Output latches LOW — the transistor pulls Pin 3 to GND, turning the LED on. It stays on when the magnet is removed.'},\n  north:{t:'North pole applied — BRP triggered',b:'North pole field exceeds the \u003cstrong\u003eBurst Release Point (BRP)\u003c\/strong\u003e. Output latches HIGH — the transistor turns off, Pin 3 floats high via the pull-up. It stays off when the magnet is removed.'},\n  none_on:{t:'Magnet removed — latched ON',b:'No magnetic field present but the US1881 \u003cstrong\u003eholds its last state\u003c\/strong\u003e. Output stays LOW. The latch retains state until the north pole is applied.'},\n  none_off:{t:'Magnet removed — latched OFF',b:'No magnetic field present but the US1881 \u003cstrong\u003eholds its last state\u003c\/strong\u003e. Output stays HIGH. The latch retains state until the south pole is applied.'},\n  none_unknown:{t:'Power-up state',b:'Output is \u003cstrong\u003eundefined at power-up\u003c\/strong\u003e. Apply a magnetic pole to the flat face of the sensor to establish a known state.'}\n};\nfunction nzndApply(pole){\n  state.pole=pole;\n  if(pole==='south') state.latch='on';\n  else if(pole==='north') state.latch='off';\n  render();\n}\nwindow.nzndApply=nzndApply;\nfunction setMagnetPoles(facingPole){\n  var leftRect=document.getElementById('nznd-left-rect');\n  var leftLbl=document.getElementById('nznd-left-lbl');\n  var rightRect=document.getElementById('nznd-right-rect');\n  var rightLbl=document.getElementById('nznd-right-lbl');\n  if(!leftRect) return;\n  if(facingPole==='south'){\n    leftRect.setAttribute('fill','#FDDDD9');leftRect.setAttribute('stroke','#E05C45');\n    leftLbl.textContent='N';leftLbl.setAttribute('fill','#7a1a0a');\n    rightRect.setAttribute('fill','#DDEEFF');rightRect.setAttribute('stroke','#5B9BD5');\n    rightLbl.textContent='S';rightLbl.setAttribute('fill','#1a4a7a');\n  } else if(facingPole==='north'){\n    leftRect.setAttribute('fill','#DDEEFF');leftRect.setAttribute('stroke','#5B9BD5');\n    leftLbl.textContent='S';leftLbl.setAttribute('fill','#1a4a7a');\n    rightRect.setAttribute('fill','#FDDDD9');rightRect.setAttribute('stroke','#E05C45');\n    rightLbl.textContent='N';rightLbl.setAttribute('fill','#7a1a0a');\n  } else {\n    leftRect.setAttribute('fill','#DDEEFF');leftRect.setAttribute('stroke','#5B9BD5');\n    leftLbl.textContent='S';leftLbl.setAttribute('fill','#1a4a7a');\n    rightRect.setAttribute('fill','#FDDDD9');rightRect.setAttribute('stroke','#E05C45');\n    rightLbl.textContent='N';rightLbl.setAttribute('fill','#7a1a0a');\n  }\n}\nfunction render(){\n  var p=state.pole,l=state.latch;\n  var bs=document.getElementById('nznd-bs');\n  var bn=document.getElementById('nznd-bn');\n  var br=document.getElementById('nznd-br');\n  if(bs){bs.className='nzndemo__btn'+(p==='south'?' s-active':'');}\n  if(bn){bn.className='nzndemo__btn'+(p==='north'?' n-active':'');}\n  if(br){br.className='nzndemo__btn nzndemo__btn-full'+(p==='none'?' r-active':'');}\n  var led=document.getElementById('nznd-led');\n  var ledlbl=document.getElementById('nznd-ledlbl');\n  var pin=document.getElementById('nznd-pin');\n  var badge=document.getElementById('nznd-badge');\n  var maglbl=document.getElementById('nznd-mag-lbl');\n  var ititle=document.getElementById('nznd-ititle');\n  var ibody=document.getElementById('nznd-ibody');\n  var lines=document.getElementById('nznd-lines');\n  var magG=document.getElementById('nznd-mag');\n  var isOn=l==='on';\n  var isUnk=l==='unknown';\n  if(led){\n    led.setAttribute('fill',isOn?'#22C55E':'#F7F8FA');\n    led.setAttribute('stroke',isOn?'#16A34A':'#CBD5E0');\n  }\n  if(ledlbl){\n    ledlbl.textContent=isUnk?'?':(isOn?'ON':'OFF');\n    ledlbl.setAttribute('fill',isOn?'#15803D':isUnk?'#5b6573':'#E05C45');\n  }\n  if(pin) pin.textContent=isUnk?'—':(isOn?'LOW (0V)':'HIGH');\n  if(badge){\n    badge.className='nzndemo__badge'+(isUnk?'':isOn?' bon':' boff');\n    badge.textContent=isUnk?'undefined':(isOn?'latched ON':'latched OFF');\n  }\n  if(maglbl) maglbl.textContent=p==='south'?'south pole':p==='north'?'north pole':'removed';\n  if(magG){\n    magG.setAttribute('transform',(p==='south'||p==='north')?'translate(52,62)':'translate(8,62)');\n  }\n  setMagnetPoles(p);\n  if(lines){\n    if(p==='south'||p==='north'){\n      lines.style.opacity='1';\n      var lns=lines.querySelectorAll('line');\n      var arr=document.getElementById('nznd-arr1');\n      var col=p==='south'?'#5B9BD5':'#E05C45';\n      lns.forEach(function(ln){ln.setAttribute('stroke',col);});\n      if(arr) arr.setAttribute('fill',col);\n      if(p==='north'){\n        lns[0].setAttribute('x1','182');lns[0].setAttribute('x2','130');\n        lns[1].setAttribute('x1','182');lns[1].setAttribute('x2','130');\n        lns[2].setAttribute('x1','182');lns[2].setAttribute('x2','130');\n        if(arr) arr.setAttribute('points','130,93 120,98 130,103');\n      } else {\n        lns[0].setAttribute('x1','130');lns[0].setAttribute('x2','182');\n        lns[1].setAttribute('x1','130');lns[1].setAttribute('x2','182');\n        lns[2].setAttribute('x1','130');lns[2].setAttribute('x2','182');\n        if(arr) arr.setAttribute('points','182,93 192,98 182,103');\n      }\n    } else {\n      lines.style.opacity='0';\n    }\n  }\n  var key=p==='south'?'south':p==='north'?'north':(l==='on'?'none_on':l==='off'?'none_off':'none_unknown');\n  if(ititle) ititle.textContent=msgs[key].t;\n  if(ibody) ibody.innerHTML=msgs[key].b;\n}\nrender();\n})();\n\u003c\/script\u003e","brand":"NZN Electronics","offers":[{"title":"Default Title","offer_id":42868153581664,"sku":"US1881-HALL-10PK","price":0.89,"currency_code":"NZD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0664\/6127\/0112\/files\/US1881ProductHero.png?v=1781518273","url":"https:\/\/www.nznelectronics.co.nz\/products\/us1881-bipolar-hall-effect-latch","provider":"NZN Electronics","version":"1.0","type":"link"}