RATIOMETRIC, LINEAR HALL-EFFECT SENSORS FOR HIGH-TEMPERATURE OPERATION

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1 356, 357, , 357, 358 V CC X The 356, 357, and 358 comprise a family of sensitive, temperature-stable linear Hall-effect sensors. Ratiometric, linear Hall-effect sensors provide a voltage output that is proportional to the applied magnetic field and have a quiescent output voltage that is approximately 5% of the supply voltage. These magnetic sensors are ideal for use in linear and rotary position sensing systems in the harsh environments of automotive and industrial applications over extended temperatures to -4 C and +15 C. The three devices in this series are similar except for temperature stability over the operating temperature range. ee the Magnetic Characteristics table for complete, individual device parametrics. ata heet * 1 UPPLY 2 GROU 3 OUTPUT wg. PH-6 Pinning is shown viewed from branded side. BOLUTE MXIMUM RTIG upply Voltage, V CC V Output Voltage, V O V Output ink Current, I O m Magnetic Flux ensity, B... Unlimited Package Power issipation, P... ee Graph Operating Temperature Range, T uffix C to +85 C uffix E C to +85 C uffix L...-4 C to +15 C torage Temperature Range, T C to +17 C Each monolithic circuit integrates a quadratic Hall element, improved temperature compensating circuitry to reduce the intrinsic sensitivity drift of the Hall element, a small-signal high-gain amplifier, and a rail-to-rail low-impedance output stage. Many problems normally associated with low-level analog signals are minimized by having the Hall element and amplifier in a single chip. Output precision is obtained by internal gain and offset trim adjustments during the manufacturing process. These devices are supplied in a 3-pin mini-ip U package or a 3-pin ultra-mini-ip U package. FETURE Output Voltage Proportional to pplied Magnetic Field Ratiometric Rail-to-Rail Output Improved ensitivity uperior Temperature tability 4.5 V to 5.5 V Operation mall Package ize olid-tate Reliability lways order by complete part number: Operating Output Offset with Temp., V OQ( T) Temperature Range ±2 G ±35 G ±5 G -2 C to +85 C 358U 358U -4 C to +85 C 357EU 357EU -4 C to +15 C 356LU 357LU 356LU 357LU Microystems, Inc.

2 FUCTIOL BLOCK IGRM 7 1 X V CC 3 2 OUTPUT GROU wg. FH-11 LLOWBLE PCKGE POWER IIPTIO in MILLIWTT "U" PCKGE RθJ = 183 C/W "U" PCKGE RθJ = 26 C/W MBIET TEMPERTURE in C wg. GH-46 ELECTRICL CHRCTERITIC over operating temperature range, at V CC = 5 V (unless otherwise noted). evice Limits Characteristic ymbol Type* Test Conditions Min. Typ. Max. Units upply Voltage V CC ll Operating V upply Current I CC ll B =, V CC = 5.5 V, I O = 1 m Quiescent V OQ 356 B =, I O = 1 m, T = 25 C V Voltage Output 357/ V 356 B =, I O = 1 m V 357/ V Output Voltage V OH ll B = +X, I O = 1 m V V OL ll B = -X, I O = -1 m.2.5 V Bandwidth (-3 db) BW ll 2 khz Output Resistance r O ll Ω Wide-Band e o ll B =, BW = 1 Hz to 1 khz, 125 µv Output oise T = 25 C egative current is defined as coming out of (sourcing) the output. * Complete part number includes the llegro prefix, and a suffix to identify operating temperature range (, E, or L ) and package type ( U or U). ee first page for available combinations. This test requires positive and negative fields sufficient to swing the output driver between fully OFF and saturated (O), respectively. It is OT intended to indicate a range of linear operation. 115 Microystems, Inc. 115 ortheast Cutoff, Box 1536 Worcester, Massachusetts (58) Copyright 1994 llegro Microystems, Inc.

3 MGETIC CHRCTERITIC over operating temperature range, at V CC = 5 V, I O = 1 m (unless otherwise noted). Part umbers* 356L- 357L- 357E Characteristic Min. Typ. Max. Min. Typ. Max. Min. Typ. Max. Min. Typ. Max. Units Operating Temp. Range, T C ensitivity at T = 25 C mv/g over Oper. Temp. Range mv/g ens ( T) at T = Max % at T = Min % V OQ( T) ±2 ±35 ±35 ±5 G Ratiometry, V OQ( V) % Ratiometry, ens ( V) % Positive Linearity, Lin % egative Linearity, Lin % ymmetry % Magnetic flux density is measured at most sensitive area of device located.15" (.38 mm) below the branded face of the U package;.18" (.46 mm) below the branded face of the U package. * Complete part number includes a suffix to indicate package type ( U or U). ee Characteristics efinitions for test conditions. The nominal sensitivity temperature stability is designed to compensate for the temperature coefficient of samariumcobalt magnets (-.2%/ C). This calculation (formula 1, next page) yields the device s equivalent accuracy, over the operating temperature range, in gauss.

4 CHRCTERITIC EFIITIO Quiescent Voltage Output. In the quiescent state (no magnetic field), the output is ideally equal to one-half of the supply voltage over the operating voltage and temperature range (V OQ V CC /2). ue to internal component tolerances and thermal considerations, there is a tolerance on the quiescent voltage output and on the quiescent voltage output as a function of supply voltage and ambient temperature. For purposes of specification, the quiescent voltage output as a function of temperature is defined as V OQ( T) = V OQ(T) V OQ(25 C) ens (25 C) This calculation yields the device s equivalent accuracy, over the operating temperature range, in gauss. ensitivity. The presence of a south-pole magnetic field perpendicular to the package face (the branded surface) will increase the output voltage from its quiescent value toward the supply voltage rail by an amount proportional to the magnetic field applied. Conversely, the application of a north pole will decrease the output voltage from its quiescent value. This proportionality is specified as the sensitivity of the device and is defined as ens = V V O(5G) O(-5G) 1 G The stability of sensitivity as a function of temperature is defined as (1) (2) ens ( T) = ens (T) ens (25 C) x 1% (3) ens (25 C) Ratiometry. The 356, 357, and 358 feature a ratiometric output. The quiescent voltage output and sensitivity are proportional to the supply voltage (ratiometric). The per cent ratiometric change in the quiescent voltage output is defined as V OQ( V) = V OQ(VCC) / V OQ(5V) x 1% (4) V CC / 5 V and the per cent ratiometric change in sensitivity is defined as ens ( V) = ens (VCC) / ens (5V) x 1% (5) V CC / 5 V Linearity and ymmetry. The on-chip output stage is designed to provide a linear output to within 5 mv of either rail with a supply voltage of 5 V. This is equivalent to approximately ±8 gauss of ambient field. lthough application of stronger magnetic fields will not damage these devices, it will force the output into a non-linear region. Linearity in per cent is measured and defined as and output symmetry as Lin+ = V O(5G) V OQ x 1% (6) 2 (V O(25G) V OQ ) Lin = V O(-5G) V OQ x 1% (7) 2 (V O(-25G) V OQ ) ym = V O(5G) V OQ x 1% (8) V OQ V O(-5G) 115 Microystems, Inc. ortheast Cutoff, Box 1536 Worcester, Massachusetts (58) 853-5

5 PPLICTIO IFORMTIO EOR LOCTIO Calibrated linear Hall devices, which can be used to determine the actual flux density presented to the sensor in a particular application, are available. For safe, reliable operation, the output should not be pulled above the supply voltage or pulled below the device ground. For optimum performance, a 1 pf capacitor between the output and ground should be added. The nominal sensitivity is factory set to compensate for the temperature coefficient of samarium-cobalt magnets (-.2%/ C). CTIVE RE EPTH.15".38 mm OM BRE URFCE UFFIX U.91" 2.3 mm.73" 1.85 mm The ratiometric feature is especially valuable when these devices are used with an analog-to-digital converter. / converters typically derive their LB step size by ratioing off a reference voltage line. If the reference voltage varies, the LB will vary proportionally. This is a major error source in many sensing systems. The 356/7/8 can eliminate this source of error by their ratiometric operation. Because their gain and offsets are proportional to the supply voltage, if they are powered from the / reference voltage, the sensor output voltage will track changes in the LB value. Extensive applications information on Hall-effect sensors and magnets is also available in the llegro Integrated and iscrete emiconductors ata Book or pplication ote CTIVE RE EPTH.18".46 mm OM BRE URFCE UFFIX U.82" 2.7 mm wg. MH " 1.4 mm TYPICL CURRET-EIG PPLICTIO wg. MH-11-6 B x 6 G/ wg. H-5

6 TYPICL POITIO-EIG PPLICTIO (lnico 8, dimensions in inches) + VCC + VCC.21 EOR EPTH BELOW PCKGE FCE RELTIVE MGETIC FLUX EITY RELTIVE OUTPUT VOLTGE RELTIVE MGETIC FLUX EITY.19 VOQ RELTIVE OUTPUT VOLTGE VOQ RELTIVE ITCE (TOTL EFFECTIVE IR GP) wg. GH G RELTIVE ITCE wg. GH-49 + VCC + VCC.19 EFFECTIVE IR GP EFFECTIVE IR GP =.5 RELTIVE MGETIC FLUX EITY VOQ RELTIVE OUTPUT VOLTGE RELTIVE MGETIC FLUX EITY EFFECTIVE IR GP =.75 EFFECTIVE IR GP = RELTIVE OUTPUT VOLTGE - G RELTIVE ITCE wg. GH-48 VOQ RELTIVE ITCE wg. GH Microystems, Inc. ortheast Cutoff, Box 1536 Worcester, Massachusetts (58) 853-5

7 PCKGE EIGTOR U imensions in Inches imensions in Millimeters (Based on 1" = 25.4 mm) MX MX MI MI EE OTE EE OTE.1.5 wg. MH-3C in wg. MH-3C mm OTE: 1. Tolerances on package height and width represent allowable mold offsets imensions given are measured at the widest point (parting line). 2. Exact body and lead configuration at vendor s option within limits shown. 3. Height does not include mold gate flash. 4. Recommended minimum PWB hole diameter to clear transition area is.35" (.89 mm).

8 PCKGE EIGTOR U imensions in Inches imensions in Millimeters (Based on 1" = 25.4 mm) MX MX.79.6 MI MI.38 EE OTE.16 EE OTE.41.5 BC wg. MH-14C in 1.27 BC wg. MH-14C mm OTE: 1. Tolerances on package height and width represent allowable mold offsets imensions given are measured at the widest point (parting line). 2. Exact body and lead configuration at vendor s option within limits shown. 3. Height does not include mold gate flash. llegro Microystems, Inc. reserves the right to make, from time to time, such departures from the detail specifications as may be required to permit improvements in the design of its products. Components made under military approvals will be in accordance with the approval requirements. The information included herein is believed to be accurate and reliable. However, llegro Microystems, Inc. assumes no responsibility for its use; nor for any infringements of patents or other rights of third parties which may result from its use. 115 Microystems, Inc. ortheast Cutoff, Box 1536 Worcester, Massachusetts (58) 853-5

DISCONTINUED PRODUCT

DISCONTINUED PRODUCT 357 A 358 ata heet 2751.1 LIEAR HALL-EFFECT EOR IC FOR HIGH-TEMPERATURE OPERATIO V CC 1 UPPLY X 2 GROU Pinning is shown viewed from branded side. ABOLUTE MAXIMUM RATIG upply Voltage, V CC............ 6.