A3150JLT

3150 PROGRAMMABLE, CHOPPERSTABILIZED, HALL-EFFECT SWITCH The A3150JLT and A3150JUA programmable switches provide tooth/valley recognition in large gear-tooth sensing applications. Each sensor consists of a single element, chopper-stabilized Hall-effect IC that can be programmed to the desired magnetic switch point, optimizing sensor airgap and timing accuracy performance after final packaging. The small package can be easily assembled and used in conjunction with a wide variety of gear/target shapes and sizes. The two devices differ only in package style. The sensing technology used for this sensor is Hall-effect based. The sensor incorporates a single-element Hall IC that switches in response to magnetic signals created by a ferrous target. The programmability of the circuit eliminates magnet and system offsets such as those caused by tilt yet provides zero-speed detection capabilities without the associated running jitter inherent in classical digital solutions. A proprietary dynamic offset cancelation technique, with an internal high-frequency clock, reduces the residual offset voltage, which is normally caused by device overmolding, temperature dependancies, and thermal stress. This technique produces devices that have an extremely stable quiescent output voltage, are immune to mechanical stress, and have precise recoverability after temperature cycling. 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 adjustments during the manufacturing process and operate-point programming in the user’s application. This sensor system is ideal for use in gathering speed, position, and timing information using gear-tooth-based configurations. The A3150JLT/JUA are particularly suited to those applications that require accurate duty cycle control or accurate edge detection. The lower vibration sensitivity also makes these devices extremely useful for transmission speed sensing. Continued next page Data Sheet 27621.40 X PTCT PRELIMINARY INFORMATION (subject to change without notice) ABSOLUTE MAXIMUM RATINGS at TA = 25°C Supply Voltage, VCC ........................... 26.5 V Reverse Supply Voltage, VRCC ............ -30 V Overvoltage Supply Current, ICC ..... 100 mA Magnetic Flux Density, B ............ Unlimited Output Current, IOUT ..... Internally Limited Output OFF Voltage, VOUT ................. 26.5 V Reverse Output Current, IROUT ......... -50 mA Operating Temperature Range, TA ............................... -40°C to +115°C Storage Temperature, TS ................... +170°C T C. U LY DN OO n R P E sig D NC de EE UR N E new I TFr N E fo OR0 CR 5 IS O 32 DFA — se U V CC 1 2 3 GROUND Dwg. PH-003-2 April 12, 1999 OUTPUT SUPPLY Always order by complete part number: the prefix 'A' + the basic four-digit part number + a suffix to indicate operating temperature range + a suffix to indicate package style, e.g., A3150JLT . 3150 PROGRAMMABLE, CHOPPERSTABILIZED, PRECISION, HALL-EFFECT SWITCH FUNCTIONAL BLOCK DIAGRAM 1 SUPPLY REG. PROGRAM LOGIC OFFSET ADJUST DYNAMIC OFFSET CANCELLATION POWER-UP OUTPUT SAMPLE & HOLD X LOW-PASS FILTER 3 CONTROL CURRENT LIMIT B OP V CC = 5 V 8.0 6.0 B > B OP 4.0 B < B RP 2.0 3.0 B < B RP 2.0 1.0 -50 -25 0 25 50 75 100 125 150 0 0 5 10 15 20 25 AMBIENT TEMPERATURE IN °C Dwg. GH-053-2 SUPPLY VOLTAGE IN VOLTS Dwg. GH-041-2 300 I OUT = 20 mA V CC = 4.5–24 V SATURATION VOLTAGE IN mV 200 100 0 -50 -25 0 25 50 75 100 125 150 AMBIENT TEMPERATURE IN °C Dwg. GH-040-4 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 3150 PROGRAMMABLE, CHOPPERSTABILIZED, PRECISION, HALL-EFFECT SWITCH FUNCTIONAL DESCRIPTION Chopper-Stabilized Technique. These devices use a proprietary dynamic offset cancellation technique, with an internal high-frequency clock to reduce the residual offset voltage of the Hall element that is normally caused by device overmolding, temperature dependencies, and thermal stress. This technique produces devices that have an extremely stable quiescent Hall output voltage, are immune to thermal stress, and have precise recoverability after temperature cycling. This technique will also slightly degrade the device output repeatability. The Hall element can be considered as a resistor array similar to a Wheatstone bridge. A large portion of the offset is a result of the mismatching of these resistors. The chopperstabilizing technique cancels the mismatching of the resistors by changing the direction of the current flowing through the Hall plate and Hall voltage measurement taps, while maintaining the Hall-voltage signal that is induced by the external magnetic flux. The signal is, then, captured by a sample-and-hold circuit. Operation. The output of these devices switches low (turns ON) when a magnetic field (south pole) perpendicular to the Hall sensor exceeds the operate point threshold (BOP). After turn-ON, the output is capable of sinking 25 mA and the output voltage is VOUT(SAT). When the magnetic field is reduced below the release point (BRP), the device output goes high (turns OFF). The difference in the magnetic operate and release points is the hysteresis (Bhys) of the device. This built-in hysteresis allows clean switching of the output even in the presence of external mechanical vibration and electrical noise. Applications. It is strongly recommended that an external bypass capacitor be connected (in close proximity to the Hall sensor) between the supply and ground of the device to reduce both external noise and noise generated by the chopper-stabilization technique. The simplest form of magnet that will operate these devices is a bar magnet with the south-seeking pole towards the branded surface of the device. Many other methods of operation are possible. Extensive applications information on magnets and Hall-effect sensors is also available in the Allegro Electronic Data Book AMS-702 or Application Note 27701, or REG X B +V — HALL VOLTAGE + Dwg. AH-011-2 +V VCC OUTPUT VOLTAGE B RP B OP VOUT(SAT) 0 0 FLUX DENSITY +B Dwg. GH-007-2 SUPPLY 3 PTCT 2 0.1 µF CC 1 www.allegromicro.com V Dwg. EH-013 www.allegromicro.com SAMPLE & HOLD Dwg. EH-012 OUTPUT X SUPPLY 3150 PROGRAMMABLE, CHOPPERSTABILIZED, PRECISION, HALL-EFFECT SWITCH PROGRAMMING PROTOCOL The A3150JLT and A3150JUA operate points are programmed by serially addressing the device through the supply terminal (pin1). After the correct operate point is determined, the device programming bits are selected and then a “lock” set to prevent any further (accidental) programming. Program Enable. To program the device, a sequence of pulses is used to activate/enable the addressing mode as shown in figure 1. This sequence of a VPP pulse, at least seven VPH pulses, and a VPP pulse with no supply interruptions, is designed to prevent the device from being programmed accidentally (for example, as a result of noise on the supply line). VPP PROGRAM ENABLE (AT LEAST 7 PULSES) VPH VPL td(1) 0 td(1) td(0) Figure 1 — Program enable Dwg. WH-013 PROGRAMMING PROTOCOL over operating temperature range. Limits Characteristic Programming Voltage Symbol VPL VPH VPP Programming Current Pulse Width IPP td(0) td(1) tdP Pulse Rise Time Pulse Fall Time tr tf Max. supply current during programming OFF time between bits Enable, address, program, or lock bit ON time Program pulse ON time VPL to VPH or VPP VPH or VPP to VPL Description Minimum voltage during programming Min. 4.5 9.0 20 – 20 20 100 11 5.0 Typ. 5.0 10 23 250 – – 300 – – Max. 5.5 11 25 – – – – – – Units V V V mA µs µs µs µs µs NOTE: Typical data is at TA = +25°C and is for design information only. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 3150 PROGRAMMABLE, CHOPPERSTABILIZED, PRECISION, HALL-EFFECT SWITCH Address Determination. The operate point is adjustable in 64 increments. With the appropriate target or gear* in position, the 64 switch points are sequentially selected (figure 2) until the required operate point is reached. Note that the difference between the operate point and the release point (hysteresis) is a constant for all addresses. Set-Point Programming. After the desired set-point address is determined (0 through 63), each bit of the equivalent binary address is programmed individually. For example, as illustrated in figure 3, to program address code 5 (binary 000101), bits 1 and 3 need to be programmed. Each bit is programmed during the wide VPP pulse and is not reversible. Lock Programming. After the desired set point is programmed, the program lock is then activated (figure 4) to prevent further programming of the device. ADDRESS N-2 ADDRESS N-1 td(0) VPH VPL td(1) 0 Dwg. WH-014 Figure 2 — Address determination VPP PROGRAM ENABLE BIT 3 PROGRAM (000100) ADDRESS 4 PROGRAM ENABLE VPH VPL td(1) 0 td(1) td(0) tdP Figure 3 — Set-point programming VPP PROGRAM ENABLE LOCK PROGRAM (65 PULSES) VPH VPL td(1) 0 Dwg. WH-016 td(1) td(0) tdP Figure 4 — Lock programming * In application, the terms “gear” and “target” are often interchanged. However, “gear” is preferred when motion is transferred. www.allegromicro.com BIT 1 PROGRA Dwg. WH-015 ADDRESS N (UP TO 63) ADDRESS 0 ADDRESS 1 ADDRESS 2 3150 PROGRAMMABLE, CHOPPERSTABILIZED, PRECISION, HALL-EFFECT SWITCH CRITERIA FOR DEVICE QUALIFICATION All Allegro sensors are subjected to stringent qualification requirements prior to being released to production. To become qualified, except for the destructive ESD tests, no failures are permitted. Qualification Test Biased Humidity (HAST) High-Temperature Operating Life (HTOL) Accelerated HTOL Test Method and Test Conditions TA = 130°C, RH = 85% JESD22-A108, TA = 150°C, TJ = 165°C JESD22-A108, TA = 175°C, TJ = 190°C JESD22-A102, Condition C, TA = 121°C, 15 psig MIL-STD-883, Method 1008, TA = 170°C MIL-STD-883, Method 1010, -65°C to +150°C — Test Length 50 hrs 408 hrs Samples 77 77 Comments VCC = VOUT = 5 V VCC = 24 V, VOUT = 20 V VCC = 24 V, VOUT = 20 V 504 hrs 77 Autoclave, Unbiased 96 hrs 77 High-Temperature (Bake) Storage Life Temperature Cycle 1000 hrs 77 500 cycles 77 Latch-Up Pre/Post Reading Pre/Post Reading Pre/Post Reading — 6 Electro-Thermally Induced Gate Leakage ESD, Human Body Model Electrical Distributions — 6 CDF-AEC-Q100-002 x per test 30 Test to failure, All leads > TBD Per Specification 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 3150 PROGRAMMABLE, CHOPPERSTABILIZED, PRECISION, HALL-EFFECT SWITCH (±0.005” [0.13 mm] die placement) Package Designator “LT” ACTIVE AREA DEPTH 0.030" 0.76 mm NOM SENSOR LOCATIONS 0.088" 2.24 mm 0.045" 1.14 mm A 1 2 3 Dwg. MH-008-8 Package Designators “UA” and "UA-TL" ACTIVE AREA DEPTH 0.018" 0.46 mm NOM 0.080" 2.04 mm 0.056" 1.44 mm A BRANDED SURFACE 1 2 3 Dwg. MH-011-9A Although sensor location is accurate to three sigma for a particular design, product improvements may result in small changes to sensor location. Allegro www.allegromicro.com 3150 PROGRAMMABLE, CHOPPERSTABILIZED, PRECISION, HALL-EFFECT SWITCH PACKAGE DESIGNATOR 'LT' (SOT-89/TO-243AA) Dimensions in Inches (for reference only) Dimensions in Millimeters (controlling dimensions) 0.181 0.173 0.072 0.064 0.167 0.155 0.102 0.090 0.063 0.055 0.0173 0.0138 4.60 4.40 1.83 1.62 4.25 3.94 2.60 2.29 1.60 1.40 0.44 0.35 1 2 3 0.090 0.084 1 2 3 2.29 2.13 0.047 0.035 0.059 BSC 0.0189 0.0142 0.0221 0.0173 0.118 BSC Dwg. MA-009-3A in 1.20 0.89 1.50 BSC 0.48 0.36 0.56 0.44 3.00 BSC Dwg. MA-009-3A mm 0.098 0.079 B A 0.031 0.102 0.181 3 0.047 0.031 TYP 2.5 2.0 B A 0.8 2.6 4.6 1.2 0.8 TYP 1 0.028 TYP 2 1 0.7 TYP 2 3 ads 1, 2, 3, and A — Standard SOT-89 Layout ads 1, 2, 3, and B — Low-Stress Version ads 1, 2, and 3 only — Lowest Stress, But Not Self Aligning Dwg. MA-012-3 in Pads 1, 2, 3, and A — Standard SOT-89 Layout Pads 1, 2, 3, and B — Low-Stress Version Pads 1, 2, and 3 only — Lowest Stress, But Not Self Aligning Dwg. MA-012-3 mm NOTE: Exact body and lead configuration at vendor’s option within limits shown. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 3150 PROGRAMMABLE, CHOPPERSTABILIZED, PRECISION, HALL-EFFECT SWITCH PACKAGE DESIGNATOR 'UA' Dimensions in Inches (controlling dimensions) 0.164 0.159 Dimensions in Millimeters (for reference only) 4.17 4.04 45° 0.062 0.058 45° 1.57 1.47 0.122 0.117 45° 0.031 3.10 2.97 45° 0.79 0.085 MAX 1 2 3 2.16 MAX 1 2 3 0.640 0.600 0.0173 0.0138 16.26 15.24 0.44 0.35 SEE NOTE 0.0189 0.0142 SEE NOTE 0.48 0.36 0.050 BSC Dwg. MH-014E in 1.27 BSC Dwg. MH-014E mm Surface-Mount Lead Form (Suffix '-TL') 0.095 ±0.005 2.41 ±0.13 0.002 MAX 0.051 MAX 0.004 0°–8° MAX 0.020 MIN FLAT Dwg. MH-015 in 0.10 MAX 0°–8° 0.51 MIN FLAT Dwg. MH-015 mm NOTES: 1. Tolerances on package height and width represent allowable mold offsets. Dimensions 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 0.035” (0.89 mm). 5. Where no tolerance is specified, dimension is nominal. www.allegromicro.com 3150 PROGRAMMABLE, CHOPPERSTABILIZED, PRECISION, HALL-EFFECT SWITCH The products described herein are manufactured under one or more of the following U.S. patents: 5,045,920; 5,264,783; 5,442,283; 5,389,889; 5,581,179; 5,517,112; 5,619,137; 5,621,319; 5,650,719; 5,686,894; 5,694,038; 5,729,130; 5,917,320; and other patents pending. Allegro MicroSystems, 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 performance, reliability, or manufacturability of its products. Before placing an order, the user is cautioned to verify that the information being relied upon is current. Allegro products are not authorized for use as critical components in life-support appliances, devices, or systems without express written approval. The information included herein is believed to be accurate and reliable. However, Allegro MicroSystems, Inc. assumes no responsibility for its use; nor for any infringements of patents or other rights of third parties that may result from its use. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000