|
|
|
부품번호 | A3425 기능 |
|
|
기능 | DUAL/ CHOPPER-STABILIZED/ ULTRA-SENSITIVE/ BIPOLAR HALL-EFFECT SWITCH | ||
제조업체 | Allegro MicroSystems | ||
로고 | |||
전체 12 페이지수
3425
DUAL, CHOPPER-STABILIZED, ULTRA-SENSITIVE,
BIPOLAR HALL-EFFECT SWITCH
V CC
12
34
Dwg. PH-017
Pinning is shown viewed from branded side.
PRELIMINARY INFORMATION
(subject to change without notice)
August 21, 2000
ABSOLUTE MAXIMUM RATINGS
at TA = +25°C
Supply Voltage, VCC ........................ 26.5 V
Reverse Battery Voltage, VRCC .......... -18 V
Zener Current, IZ ............................ 100 mA
Magnetic Flux Density, B ........... Unlimited
Output Off Voltage, VOUT .................... VCC
Output Current, IOUT ........................ 30 mA
Reverse Output Current, IOUT ........ -50 mA
Package Power Dissipation, PD . See Graph
Junction Temperature, TJ ............... +170°C
Operating Temperature Range,
TA, ............................ -40°C to +150°C
Storage Temperature Range,
TS .............................. -65°C to +170°C
The A3425LK dual Hall-effect switch is an extremely
temperature-stable and stress-resistant sensor especially suited for use in
digital-encoder systems in the harsh environments of automotive or
industrial applications over extended temperature ranges to +150°C.
Superior high-temperature performance is made possible through
dynamic offset cancellation, which reduces the residual offset voltage
normally caused by device overmolding, temperature dependencies, and
thermal stress. This device also eliminates the major manufacturing
hurdles encountered in fine-pitch direction-detection applications,
namely maintaining accurate mechanical location between the two active
Hall elements. Here, the two Hall elements are photolithographically
aligned to better than 1 µm, as contrasted with 100 µm or worse me-
chanical location tolerance when manufactured discretely. The
A3425LK is an ultra-sensitive device optimized for use with high-
density ring magnets.
The device includes on a single silicon chip a voltage regulator, two
independent chopper-stabilized Hall-voltage generators , two small-
signal amplifiers, two Schmitt triggers, and two short-circuit protected
open-collector outputs to sink up to 30 mA each. An on-board regulator
permits operation with supply voltages of 3.3 to 26.5 volts. With
suitable output pull ups, it can be used directly with bipolar or MOS
logic circuits.
The A3425LK dual Hall-effect switch is supplied in a 4-pin plastic
SIP for operation over a temperature range of -40°C to +150°C. A
similar device, with on-chip logic processing specifically for direction
detection applications, in a 5-pin SIP, is the A3422LKA.
FEATURES
I Two Matched Hall Switches On A Single Substrate
I 1 mm Sensor-to-Sensor Spacing
I Superior Temperature Stability
I Resistant to Physical Stress
I Output Short-Circuit Protection
I Operation From Unregulated Supply
I Reverse Battery Protection
I Solid-State Reliability
I Integrated ESD Protection on Outputs and Supply
Always order by complete part number, e.g., A3425LK .
3425
DUAL, CHOPPER-STABILIZED,
ULTRA-SENSITIVE,
BIPOLAR HALL-EFFECT SWITCH
TYPICAL OPERATING CHARACTERISTICS
as a function of temperature
25
20
15
10
5
0
-5
-10
-15
-20
-25
-50
CHANNEL 1 SWITCH POINTS
OPERATE POINT
VCC = 18-26.5 V
VCC = 3.3-5 V
VCC = 5 V
VCC = 3.3 V
VCC = 18 V
VCC = 26.5 V
RELEASE POINT
-25 0 25 50 75 100 125 150
AMBIENT TEMPERATURE IN °C
Dwg. GH-026-7
25
20
15
10
5
0
-5
-10
-15
-20
-25
-50
CHANNEL 2 SWITCH POINTS
OPERATE POINT
VCC = 26.5 V
VCC = 18 V
VCC = 3.3-5 V
VCC = 26.5 V
VCC = 5 V
VCC = 18 V
VCC = 3.3 V
RELEASE POINT
-25 0
25 50 75 100 125 150
AMBIENT TEMPERATURE IN °C
Dwg. GH-026-8
OUTPUT SATURATION VOLTAGE
300
VCC = 3.3 V
200
VCC = 26.5 V
100
IOUT = 20 mA
TOTAL SUPPLY CURRENT
8 B ≥ BOP
6
VCC = 18 V
VCC = 3.3 V
B ≤ BRP
4
2
VCC = 18 V
VCC = 3.3 V
0
-50 -25
0 25 50 75 100
AMBIENT TEMPERATURE IN °C
125 150
Dwg. GH-029-5
0
-50 -25
0 25 50 75 100
AMBIENT TEMPERATURE IN °C
125 150
Dwg. GH-028-8
115 Northeast Cutoff, Box 15036
4 Worcester, Massachusetts 01615-0036 (508) 853-5000
4페이지 3425
DUAL, CHOPPER-STABILIZED,
ULTRA-SENSITIVE,
BIPOLAR 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 chopper-stabilizing technique cancels the mismatch-
ing of the resistors by changing the direction of the current
flowing through the Hall plate and Hall voltage measure-
ment 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.
More detailed descriptions of the circuit operation can
be found in: Technical Paper STP 97-10, Monolithic
Magnetic Hall Sensor Using Dynamic Quadrature Offset
Cancellation and Technical Paper STP 99-1, Chopper-
Stabilized Amplifiers With A Track-and-Hold Signal
Demodulator.
Operation. The output of these devices switches low
(turns on) when a magnetic field perpendicular to the Hall
sensor exceeds the operate point threshold (BOP). After
turn-on, the output is capable of sinking 30 mA and the
output voltage is VOUT(SAT). When the magnetic field is
reduced below the release point (BRP), the device output
switches high (turns off). Note especially that release can
occur when the magnetic field is removed but to ensure
release, a field reversal is required. 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.
REG
X
B
+V
+V
VCC
—
HALL
VOLTAGE
+
Dwg. AH-011-2
Dwg. EH-012
0
-B
B RP
B OP
0
FLUX DENSITY
VOUT(SAT)
+B
Dwg. GH-034-5
www.allegromicro.com
7
7페이지 | |||
구 성 | 총 12 페이지수 | ||
다운로드 | [ A3425.PDF 데이터시트 ] |
당사 플랫폼은 키워드, 제품 이름 또는 부품 번호를 사용하여 검색할 수 있는 |
구매 문의 | 일반 IC 문의 : 샘플 및 소량 구매 ----------------------------------------------------------------------- IGBT, TR 모듈, SCR 및 다이오드 모듈을 포함한 광범위한 전력 반도체를 판매합니다. 전력 반도체 전문업체 상호 : 아이지 인터내셔날 사이트 방문 : [ 홈페이지 ] [ 블로그 1 ] [ 블로그 2 ] |
부품번호 | 상세설명 및 기능 | 제조사 |
A3421EKA | HALL-EFFECT/ DIRECTION-DETECTION SENSORS | Allegro MicroSystems |
A3421LKA | HALL-EFFECT/ DIRECTION-DETECTION SENSORS | Allegro MicroSystems |
DataSheet.kr | 2020 | 연락처 | 링크모음 | 검색 | 사이트맵 |