A3295 Chopper-Stabilized, Precision Hall-Effect Switch for Consumer and Industrial Applications

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for onsumer and Industrial pplications FTURS N NFITS Resistant to physical stress Superior temperature stability Output short-circuit protection Operation from unregulated supply Reverse battery

1 for onsumer and Industrial pplications FTURS N NFITS Resistant to physical stress Superior temperature stability Output short-circuit protection Operation from unregulated supply Reverse battery protection Solid-state reliability Small package size PKGS: Not to scale 3-pin SOT23W (suffix LH) 3-pin SIP, matrix H style (suffix U) NOT FOR NW SIGN 3-pin SIP, chopper style (suffix U) SRIPTION The 3295 Hall-effect switch is an extremely temperaturestable and stress-resistant sensor I unipolar switch, especially suited for operation over extended temperature ranges (up to 125 ). Superior high-temperature performance is made possible through dynamic offset cancellation, which reduces the residual offset voltage normally caused by device package overmolding, temperature dependencies, and thermal stress. The device is not intended for automotive applications. The device includes, on a single silicon chip, a voltage regulator, a Hall voltage generator, a small-signal amplifier, chopper stabilization, a Schmitt trigger, and a short-circuit protected open-drain output to sink up to 25 m. south polarity magnetic field of sufficient strength is required to turn the output on. n onboard regulator permits operation with supply voltages in the range of 3 to 24 V. Two package styles provide a magnetically optimized package for most applications: type LH is a miniature SOT23W lowprofile surface-mount package, and type U is a three-lead ultramini SIP for through-hole mounting. oth packages are lead (Pb) free, with 100% matte-tin-plated leadframes. V Regulator ynamic Offset ancellation mp Sample and Hold Low-Pass Filter ontrol urrent Limit OUT 1Ω GN Functional lock iagram 3295-S, Rev. 13 November 4, 2016

2 SPIFITIONS SLTION GUI Part Number Packing [1] Package Type 3295KLHLT-T 3000 pieces per 7-in. reel Surface-mount SOT23W 3295KLHLX-T pieces per 13-in. reel Surface-mount SOT23W 3295KU-T [3] 500 pieces per bulk bag Through-hole ultramini SIP Magnetic Switchpoints [2] Operate, OP (G) Release, RP (G) 75 (max) 5 (min) 1 ontact llegro for additional packing options. 2 1 G (gauss) = 0.1 mt (millitesla). 3 The chopper-style U package is not for new design; the matrix H style U package is recommended for new designs. SOLUT MXIMUM RTINGS haracteristic Symbol Notes Rating Units Supply Voltage V 26.5 V Reverse attery Voltage V R 30 V Output Off Voltage V OUT 26 V evice provides internal current limiting to help protect itself ontinuous Output urrent I OUT from output short circuits 25 m Reverse Output urrent I ROUT 50 m Magnetic Flux ensity Unlimited G Operating mbient Temperature T Range K 40 to 125 Maximum Junction Temperature T J (max) 165 Storage Temperature T stg 65 to PTT 1 2 PTT Terminal List Number Name LH U Function V 1 1 Power supply OUT 2 3 Output GN 3 2 Ground Package LH, 3-Pin SOT23W Pinout iagram Package U, 3-Pin SIP Pinout iagram 2

3 LTRIL HRTRISTIS: Over operating temperature range, unless otherwise noted haracteristic Symbol Test onditions Min. Typ. [1] Max Units Supply Voltage Range [2] V Operating, T J < V Output Leakage urrent I OFF V OUT = 24 V, < RP 10 µ Output Saturation Voltage V OUT(ST) I OUT = 20 m, > OP mv Output urrent Limit I ON > OP m Power-On Time t PO V > 4.2 V 50 µs hopping Frequency f 800 khz Output Rise Time t R R LO = 820 Ω, LO = 20 pf µs Output Fall Time t F R LO = 820 Ω, LO = 20 pf µs Supply urrent I < RP, V = 12 V m > OP, V = 12 V m Reverse attery urrent I R V R = 20 V 5.0 m Zener Voltage V Z + V I = 15 m, T = V Zener Impedance Z Z + Z I = 15 m, T = Ω 1 Typical data at T = 25, 12 V. 2 Maximum V must be derated for power dissipation and junction temperature. See pplication Information. MGNTI HRTRISTIS: Over V range, unless otherwise noted haracteristic Symbol Test onditions Min. Typ. Max. Units Operate Point OP 75 G Release Point RP 5 G Hysteresis HYS OP RP 70 G 3

4 THRML HRTRISTIS: May require derating at maximum conditions; see application information haracteristic Symbol Test onditions [1] Value Units Package Thermal Resistance R θj 1 dditional thermal information available on llegro website. Package LH, 1-layer P with copper limited to solder pads 228 /W Package LH, 2-layer P with in. 2 of copper area each side connected by thermal vias 110 /W Package U, 1-layer P with copper limited to solder pads 165 /W Power erating urve Maximum llowable V (V) layer P, Package LH (R θj = 110 º/W) 1-layer P, Package U (R θj = 165 º/W) 1-layer P, Package LH (R θj = 228 º/W) V (max) V (min) Temperature (º) Power issipation, P (mw) Power issipation versus mbient Temperature 2-layer P, Package LH (R θj = 110 º/W) 1-layer P, Package U (R θj = 165 º/W) 1-layer P, Package LH (R θj = 228 º/W) Temperature ( ) 4

5 FUNTIONL SRIPTION hopper-stabilized Technique The Hall element can be considered as a resistor array similar to a Wheatstone bridge. basic circuit is shown in figure 1, demonstrating the effect of the magnetic field flux density,, impinging on the Hall element. When using Hall effect technology, a limiting factor for switchpoint accuracy is the small signal voltage, V HLL, developed across the Hall element. This voltage is disproportionally small relative to the offset that can be produced at the output of the Hall device, caused by device overmolding, temperature dependencies, and thermal stress. large portion of the offset is a result of the mismatching of these resistors. The 3295 uses a dynamic offset cancellation technique, with an internal high-frequency clock, to reduce the residual offset, see figure 2. The chopper-stabilizing technique cancels the mismatching of the resistor circuit by changing the direction of the current flowing through the Hall element. To do so, MOS switches and Hall voltage measurement taps are used, while maintaining V HLL signal that is induced by the external magnetic flux. The signal is then captured by a sample-and-hold circuit and further processed using low-offset bipolar circuitry. This technique produces devices that have an extremely stable quiescent Hall +V +V HLL output voltage, are immune to thermal stress, and have precise recoverability after temperature cycling. This technique will also slightly degrade the device output repeatability. relatively high sampling frequency is used in order to process faster signals. More detailed descriptions of the circuit operation can be found on the llegro website, including: Technical Paper STP 97-10, Monolithic Magnetic Hall Sensing Using ynamic Quadrature Offset ancellation, and Technical Paper STP 99-1, hopper- Stabilized mplifiers with a Track-and-Hold Signal emodulator. Operation The output of the 3295 switches low (turns on) when a magnetic field perpendicular to the Hall element transitions through and exceeds the Operate Point threshold, OP. This is illustrated in figure 3. fter turn-on, the output is capable of sinking 25 m, and the output voltage reaches V OUT(ST). Note that after a south (+) polarity magnetic field of sufficient strength impinging on the branded face of the device turns on the device, the device remains on until the magnetic field is reduced below the Release Point threshold, RP. t that transition, the device output goes high (turns off). The difference in the magnetic operate and release points is the hysteresis, HYS, of the device. This built-in hysteresis allows clean switching of the output, even in the presence of external mechanical vibration and electrical noise. V HLL Figure 1: Hall lement, asic ircuit Operation Regulator V+ Hysteresis of V OUT Switching ue to V OUT(off) mp Sample and Hold Low- Pass Filter V OUT Switch to High RP OP Switch to Low + V OUT(on)(sat) Figure 2: hopper Stabilization ircuit (ynamic Quadrature Offset ancellation) HYS Figure 3: Output Voltage Responds to Magnetic Flux ensity. 5

6 When the device is powered on, if the ambient magnetic field has an intensity that is between OP and RP, the initial output state is indeterminate. The first time that the level of either rises through OP, or falls through RP, however, the correct output state is obtained. PPLITION INFORMTION It is strongly recommended that an external bypass capacitor be connected (in close proximity to the Hall element) between the supply and ground of the device to reduce both external noise and noise generated by the chopper stabilization technique. This configuration is shown in figure 4. The simplest form of magnet that will operate these devices is a ring magnet. Other methods of operation, such as linear magnets, are possible. The device must be operated below the maximum junction temperature of the device, T J(max). Under certain combinations of peak conditions, reliable operation may require derating supplied power or improving the heat dissipation properties of the application. The Package Thermal Resistance, R θj, is a figure of merit summarizing the ability of the application and the device to dissipate heat from the junction (die), through all paths to the ambient air. Its primary component is the ffective Thermal onductivity, K, of the printed circuit board, including adjacent devices and traces. Radiation from the die through the device case, R θj, is relatively small component of R θj. mbient air temperature, T, and air motion are significant external factors, damped by overmolding. Sample power dissipation results are given in the Thermal haracteristics section. dditional thermal data is also available on the llegro website. xtensive applications information for Hall-effect devices is available in: Hall-ffect I pplications Guide, pplication Note and Guidelines for esigning Subassemblies Using Hall- ffect evices, pplication Note V 3295 V VOUT 0.1 uf GN Figure 4: Typical asic pplication ircuit bypass capacitor is highly recommended. 6

7 USTOMR PKG RWINGS For Reference Only Not for Tooling Use (Reference WG-2840) imensions in millimeters NOT TO SL imensions exclusive of mold flash, gate burrs, and dambar protrusions xact case and lead configuration at supplier discretion within limits shown ± MIN RF 0.25 S 0.95 randed Face Seating Plane Gauge Plane P Layout Reference View 8X 10 RF 1.00 ±0.13 NNT 0.95 S 0.40 ± N = Last three digits of device part number T = Temperature ode (Letter) ctive rea epth, 0.28 mm Reference land pattern layout; all pads a minimum of 0.20 mm from all adjacent pads; adjust as necessary to meet application process requirements and P layout tolerances randing scale and appearance at supplier discretion Hall elements, not to scale NNN Figure 5: Package LH, 3-Pin SOT23W N = Last three digits of device part number Standard randing Reference View 7

8 For Reference Only Not for Tooling Use (Reference WG-9049) imensions in millimeters NOT TO SL imensions exclusive of mold flash, gate burrs, and dambar protrusions xact case and lead configuration at supplier discretion within limits shown ± X 10 randed Face Mold jector Pin Indent MX 0.51 RF 0.79 RF NOM NNN ± Standard randing Reference View = Supplier emblem N = Last three digits of device part number ambar removal protrusion (6X) Gate and tie bar burr area ctiverea epth, 0.50 mm RF randing scale and appearance at supplier discretion Hall element, not to scale Figure 6: Package U, 3-Pin SIP, Matrix Style 8

9 ± randed Face 45 Mold jector Pin Indent ± MX 0.51 RF RF NOT FOR NW SIGN Standard randing Reference View NNT 1 = Supplier emblem N = Last two digits of device part number T = Temperature code For Reference Only; not for tooling use (reference WG-9049) imensions in millimeters imensions exclusive of mold flash, gate burrs, and dambar protrusions xact case and lead configuration at supplier discretion within limits shown ambar removal protrusion (6X) Gate burr area ctive rea epth, 0.50 mm RF randing scale and appearance at supplier discretion Hall element, not to scale NOM Figure 7: Package U, 3-Pin SIP, hopper Style 9

10 Revision History Number ate escription 9 November 11, 2012 onform escription 10 January 2, 2015 dded LX option to Selection Guide 11 July 13, 2015 orrected LH package ctive rea epth value 12 January 14, 2016 Updated Reverse Supply urrent test conditions in lectrical haracteristics table 13 November 4, 2016 hopper-style U package designated as not for new design opyright 2016, reserves the right to make, from time to time, such departures from the detail specifications as may be required to permit improvements in the performance, reliability, or manufacturability of its products. efore placing an order, the user is cautioned to verify that the information being relied upon is current. llegro s products are not to be used in any devices or systems, including but not limited to life support devices or systems, in which a failure of llegro s product can reasonably be expected to cause bodily harm. The information included herein is believed to be accurate and reliable. However, assumes no responsibility for its use; nor for any infringement of patents or other rights of third parties which may result from its use. For the latest version of this document, visit our website: 10

A3290 and A3291 Chopper-Stabilized, Precision Hall-Effect Latches for Consumer and Industrial Applications

A3290 and A3291 Chopper-Stabilized, Precision Hall-Effect Latches for Consumer and Industrial Applications for onsumer and Industrial pplications FTURS N NFITS Symmetrical switchpoints Resistant to physical stress Superior temperature stability Output short-circuit protection Operation from unregulated supply