A3213 and A3214 Micropower Ultra-Sensitive Hall-Effect Switches Features and Benefits Description ▪ ▪ ▪ ▪ The A3213 and A3214 integrated circuits are ultra-sensitive, pole independent Hall-effect switches with a latched digital output. They are especially suited for operation in batteryoperated, hand-held equipment such as cell and cordless telephones and palmtop computers. A 2.4 to 5.5 V operation and a unique clocking scheme reduce the average operating power requirements: the A3213 to 825 μW, the A3214 to 14 μW (typical, at 2.75 V). Except for operating duty cycle and average operating current, the A3213 and A3214 are identical. ▪ ▪ ▪ ▪ Micropower operation Operate with north or south pole 2.4 to 5.5 V battery operation Chopper stabilized ▫ Superior temperature stability ▫ Extremely low switchpoint drift ▫ Insensitive to physical stress High ESD protection Solid state reliability Small size Easily assembly into applications due to magnetic pole independence Packages 3 lead ultramini SIP (suffix UA) Unlike other Hall-effect switches, either a north or south pole of sufficient strength will turn the output on; in the absence of a magnetic field, the output is off. The polarity independence and minimal power requirement allows these devices to easily replace reed switches for superior reliability and ease of manufacturing, while eliminating the requirement for signal conditioning. Improved stability is made possible through chopper stabilization (dynamic offset cancellation), which reduces the residual offset voltage normally caused by device overmolding, temperature dependencies, and thermal stress. These devices include, on a single silicon chip, a Hall-voltage Continued on the next page… 3 pin surface mount SOT23-W (suffix LH) Not to scale Functional Block Diagram SUPPLY SWITCH LATCH OUTPUT SAMPLE & HOLD X DYNAMIC OFFSET CANCELLATION TIMING LOGIC GROUND Dwg. FH-020-5 27622.62-DS Rev. Y A3213 and A3214 Micropower Ultra-Sensitive Hall-Effect Switches Description (continued) generator, small-signal amplifier, chopper stabilization, a latch, and a MOSFET output. Advanced BiCMOS processing is used to take advantage of low-voltage and low-power requirements, component matching, very low input-offset errors, and small component geometries. miniature low-profile surface-mount package, ‘UA’ is a three-lead SIP for through-hole mounting. Each package is lead (Pb) free (suffix, –T) , with a 100% matte tin plated leadframe. Devices are rated for operation over a temperature range of –40°C to 85°C or –40°C to 150°C. Two package styles provide a magnetically optimized package for most applications. ‘LH’ is a Product Selection Guide Part Number Mounting Packing* LH package Surface Mount 7-in. reel 3000 pieces/reel A3213EUA-T UA package SIP through hole Bulk 500 pieces/bag A3213LUA-T UA package SIP through hole Bulk 500 pieces/bag LH package Surface Mount 7-in. reel 3000 pieces/reel UA package SIP through hole Bulk 500 pieces/bag A3213ELHLT-T A3214ELHLT-T A3214EUA-T Ambient*, TA (ºC) DC (%) IDD(AVG)(typ) (μA) 25 309 0.10 6 –40 to 85 –40 to 150 –40 to 85 *Contact Allegro for additional packing and operating temperature range options Absolute Maximum Ratings Characteristic Symbol Notes Rating Units VDD 6 V B Unlimited G Output Off Voltage VOUT 6 V Output Current IOUT 1 mA Supply Voltage Magnetic Flux Density Range E –40 to 85 ºC Range L –40 to 150 ºC TJ(max) 165 ºC Tstg –65 to 170 ºC Operating Ambient Temperature TA Maximum Junction Temperature Storage Temperature Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 2 A3213 and A3214 Micropower Ultra-Sensitive Hall-Effect Switches Pin-out Diagrams Name Description UA 1 1 VDD Input power supply; tie to GND with bypass capacitor 3 2 GND Ground 2 3 VOUT Output signal UA Package GND LH Package VOUT 1 2 3 VOUT 2 GND 1 VDD X 3 VDD Number LH Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 3 A3213 and A3214 Micropower Ultra-Sensitive Hall-Effect Switches ELECTRICAL CHARACTERISTICS valid over operating voltage and temperature range, unless otherwise noted Characteristic Symbol Test Conditions Supply Voltage Range VDD Operating1) Output Leakage Current IOFF VOUT = 5.5 V, BRPN < B < BRPS Output On Voltage VOUT(ON) Awake Time tawake Period tperiod Duty Cycle Chopping Frequency Supply Current A3213 Typ.1 Max. Units 2.4 3.0 5.5 V – <1.0 1.0 μA – 100 300 mV – 60 90 μs – 240 360 μs A3214, TA = 25°C, VDD = 3 V – 60 90 ms A3213 – 25 – % A3214 – 0.10 – % – 340 – kHz IDD(EN) Chip awake (enabled) – – 2.0 mA IDD(DIS) Chip asleep (disabled) – – 8.0 μA A3213 – 309 850 μA A3214 – 6 22 μA DC fC IDD(AVG) 1Typical Output on, IOUT = 1 mA, VDD = 3.0 V Min. Data is at TA = 25°C and VDD = 3.0 V and is for design information only. and release points will vary with supply voltage. BOPx = operate point (output turns ON); BRPx = release point (output turns OFF). 2Operate MAGNETIC CHARACTERISTICS1 valid over operating voltage and temperature range, unless otherwise noted Characteristic Operate Points Release Points Hysteresis Test Conditions Symbol2 Min. Typ.3 Max. Units4 BOPS South pole to branded side – 42 70 G BOPN North pole to branded side –70 –48 – G BRPS South pole to branded side 10 32 – G BRPN North pole to branded side – –38 –10 G Bhys |BOPx - BRPx| – 10 – G 1As used here, negative flux densities are defined as less than zero (algebraic convention) and -50 G is less than +10 G. 2B OPx = operate point (output turns ON); BRPx = release point (output turns OFF). 3Typical Data is at T = 25°C and V A DD = 3.0 V and is for design information only. 41 gauss (G) is exactly equal to 0.1 millitesla (mT). Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 4 A3213 and A3214 Micropower Ultra-Sensitive Hall-Effect Switches THERMAL CHARACTERISTICS may require derating at maximum conditions, see application information Characteristic Symbol Test Conditions* Value Units Package LH, 1-layer PCB with copper limited to solder pads RθJA Package Thermal Resistance Package LH, 2-layer PCB with 0.463 connected by thermal vias in.2 of copper area each side Package UA, 1-layer PCB with copper limited to solder pads 228 ºC/W 110 ºC/W 165 ºC/W *Additional thermal information available on Allegro website. Maximum Allowable VDD (V) VDD(max) VDD(min) Power Dissipation, PD (mW) Power Dissipation versus Ambient Temperature 1900 1800 1700 1600 1500 1400 1300 1200 1100 1000 900 800 700 600 500 400 300 200 100 0 2l (R aye rP QJ C A = 11 B, P 0 º ac 1-la C/ ka W (R yer PC ) ge L QJA = B H 165 , Pac k ºC/ a W) ge U A 1-lay er P (R CB, QJA = 228 Packag ºC/W e LH ) 20 40 60 80 100 120 Temperature (°C) 140 160 180 Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 5 A3213 and A3214 Micropower Ultra-Sensitive Hall-Effect Switches Typical Operating Characteristics A3213 and A3214 A3213 and A3214 Switchpoints versus Ambient Temperature 60 BOP(S) 40 BRP(S) 20 0 -20 BRP(N) -40 BOP(N) -60 -80 -60 -40 -20 0 20 VDD = 5.5 V 80 40 60 Magnetic Flux Density, B (G) 80 Magnetic Flux Density, B (G) Switchpoints versus Ambient Temperature VDD = 2.4 V 60 80 BOP(S) 40 BRP(S) 20 0 -20 BRP(N) -40 -60 BOP(N) -80 -60 100 -40 Ambient Temperature, TA (°C) -20 0 20 40 60 80 100 Ambient Temperature, TA (°C) A3213 and A3214 Switchpoints versus Supply Voltage TA = 25°C 80 Magnetic Flux Density, B (G) 60 BOP(S) 40 BRP(S) 20 0 -20 BRP(N) -40 -60 -80 BOP(N) 0 1 2 3 4 5 6 Supply Voltage, VDD (V) A3214 A3213 Average Supply Current versus Temperature Average Supply Current versus Temperature 24 Supply Current, IDD(AVG) (μA) Supply Current, IDD(AVG) (μA) 900 750 600 VDD = 5.5 V 450 VDD = 3.0 V 300 VDD = 2.4 V 150 0 -60 -40 -20 0 20 40 60 80 20 VDD = 5.5 V 16 12 8 VDD = 3.0 V 4 VDD = 2.4 V 0 -60 100 Supply Current, IDD(AVG) (μA) Supply Current, IDD(AVG) (μA) 600 450 300 150 2 3 4 Supply Voltage, VDD (V) 40 60 80 100 TA = 25°C 24 750 1 20 Average Supply Current versus Supply Voltage TA = 25°C 0 0 A3214 A3213 Average Supply Current versus Supply Voltage 0 -20 Ambient Temperature, TA (°C) Ambient Temperature, TA (°C) 900 -40 5 6 20 16 12 8 4 0 0 1 2 3 4 5 6 Supply Voltage, VDD (V) Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 6 A3213 and A3214 Micropower Ultra-Sensitive Hall-Effect Switches FUNCTIONAL DESCRIPTION PERIOD IDD(EN) +V SAMPLE & HOLD Low Average Power. Internal timing circuitry activates the IC for 60 μs and deactivates it for the remainder of the period (240 μs (typ) for the A3213 and 60 ms (typ) for the A3214). A short "awake" time allows for stabilization prior to the sampling and data latching on the falling edge of the timing pulse. The output during the "sleep" time is latched in the last sampled state. The supply current is not affected by the output state. X 60 μs "AWAKE" "SLEEP" SAMPLE & OUTPUT LATCHED IDD(DIS) Dwg. EH-012-1 0 B Chopper-Stabilized Technique. 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. 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. The chopper-stabilizing technique cancels the mismatching of the resistor circuit by changing the direction of the current flowing through the Hall plate using CMOS switches and Hall voltage measurement taps, while maintaing the Hallvoltage 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 output voltage, are immune to thermal stress, and have precise recoverability after temperature cycling. This technique will also slightly degrade the device output repeatability. A relatively high sampling frequency is used in order that faster signals can be processed. +V — HALL VOLTAGE + Dwg. AH-011-2 Operation. The output of this device switches low (turns on) when a magnetic field perpendicular to the Hall element exceeds the operate point BOPS (or is less than BOPN). After turn-on, the output is capable of sinking up to 1 mA and the output voltage is VOUT(ON). When the magnetic field is reduced below the release point BRPS (or increased above BRPN), the device output switches 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. More detailed descriptions of the circuit operation can be found in Technical Paper STP 97-10, Monolithic Magnetic Hall Sensing Using Dynamic Quadrature Offset Cancellation and As used here, negative flux densities are defined as less than Technical Paper STP 99-1, Chopper-Stabilized Amplifiers With A zero (algebraic convention) and -50 G is less than +10 G. Track-and-Hold Signal Demodulator. Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 7 A3213 and A3214 Micropower Ultra-Sensitive Hall-Effect Switches Applications. Allegro's pole-independent sensing technique allows for operation with either a north pole or south pole magnet orientation, enhancing the flexibility of the device in application assembling. The technology provides the same output polarity for either pole face. 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 is especially true due to the relatively high impedance of battery supplies. The simplest form of magnet that will operate these devices is a bar magnet with either pole near the branded surface of the device. Many other methods of operation are possible. Extensive applications information on magnets and Hall-effect devices is also available in the Allegro application note 27701, or at www.allegromicro.com OUTPUT OFF 5V MAX VOUT B OPS OUTPUT OUTPUT VOLTAGE B OPN 10 pF GND 50 k Ω VDD X SUPPLY (3 V BATTERY) 0.1 μF OUTPUT ON BRPS BRPN OUTPUT ON 0 -B 0 +B MAGNETIC FLUX Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 8 A3213 and A3214 Micropower Ultra-Sensitive Hall-Effect Switches Package LH, 3-Pin (SOT-23W) +0.12 2.98 –0.08 1.49 D 4°±4° 3 A +0.020 0.180–0.053 0.96 D +0.10 2.90 –0.20 +0.19 1.91 –0.06 2.40 0.70 D 0.25 MIN 1.00 2 1 0.55 REF 0.25 BSC 0.95 Seating Plane Gauge Plane 8X 10° REF B PCB Layout Reference View Branded Face C Standard Branding Reference View 1.00 ±0.13 NNT +0.10 0.05 –0.05 0.95 BSC 0.40 ±0.10 1 For Reference Only; not for tooling use (reference dwg. 802840) Dimensions in millimeters Dimensions exclusive of mold flash, gate burrs, and dambar protrusions Exact case and lead configuration at supplier discretion within limits shown A Active Area Depth, 0.28 mm REF B 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 PCB layout tolerances C Branding scale and appearance at supplier discretion D Hall element, not to scale N = Last two digits of device part number T = Temperature code (letter) NNN 1 N = Last three digits of device part number Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 9 A3213 and A3214 Micropower Ultra-Sensitive Hall-Effect Switches Package UA, 3-Pin SIP +0.08 4.09 –0.05 45° B C E 2.07 1.52 ±0.05 1.33 E Mold Ejector Pin Indent +0.08 3.02 –0.05 E Branded Face 45° 1 2.16 MAX D Standard Branding Reference View = Supplier emblem N = Last two digits of device part number T = Temperature code 0.79 REF A 0.51 REF NNT 1 2 3 +0.03 0.41 –0.06 15.75 ±0.51 For Reference Only; not for tooling use (reference DWG-9049) Dimensions in millimeters Dimensions exclusive of mold flash, gate burrs, and dambar protrusions Exact case and lead configuration at supplier discretion within limits shown A Dambar removal protrusion (6X) B Gate burr area C Active Area Depth, 0.50 mm REF +0.05 0.43 –0.07 D Branding scale and appearance at supplier discretion E Hall element, not to scale 1.27 NOM Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 10 A3213 and A3214 Micropower Ultra-Sensitive Hall-Effect Switches Revision History Revision Revision Date Rev. Y October 29, 2012 Description of Revision Update product selection Copyright ©2003-2012, Allegro MicroSystems, Inc. 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’s products are not to be used in life support devices or systems, if a failure of an Allegro product can reasonably be expected to cause the failure of that life support device or system, or to affect the safety or effectiveness of that device or system. The information included herein is believed to be accurate and reliable. However, Allegro MicroSystems, Inc. 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: www.allegromicro.com Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 11