A1425LK Allegro Microsystems Inc, A1425LK Datasheet - Page 11

• Manufacturer Part Number: A1425LK
• Description: IC SENSOR HALL EFFECT AC 4-SIP
• Manufacturer: Allegro Microsystems Inc
• Type: Special Purposer

Specifications of A1425LK

• Sensing Range: 11G Trip, -11G Release
• Voltage - Supply: 4 V ~ 26.5 V
• Current - Supply: 7mA
• Current - Output (max): 25mA
• Output Type: Digital, Open Collector
• Features: High Accuracy
• Operating Temperature: -40°C ~ 150°C
• Package / Case: 4-SIP
• Magnetic Type: Monolithic
• Operating Supply Voltage (min): 4V
• Operating Supply Voltage (typ): 5/9/12/15/18/24V
• Operating Supply Voltage (max): 26.5V
• Output Current: 25mA
• Package Type: SIP
• Pin Count: 4
• Mounting: Through Hole
• Operating Temp Range: -40C to 150C
• Operating Temperature Classification: Automotive
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

A1425
Target Selection
The zero-crossing switchpoints and AC-coupled operation of this
device make target selection important. For high-density target
geometries or small target features that produce a sinusoidal
magnetic signal, the high-pass fi lter is capable of fi ltering offsets
that may be induced in the fi nal device output. If such offset is
present, and the target has larger features, then the high-pass
fi lter may not be effective at higher speeds and an accuracy shift
may occur. These relationships are shown in fi gure 2.
Figure 2. Large Feature Effects. (a) Large target feature but no device offset,
normal edge position. (b) Large target feature with negative device offset, shifted
(advanced) output edge position.
+B
–B
+V
+B
–B
+V
0
0
0
0
Large Feature (Tooth)
High Accuracy Analog Speed Sensor IC with Integrated
Filter Capacitor and Dual Zero-Crossing Output Signal
Output Edge
Shift
(a)
(b)
Applications Information
Valley
Power Supply Protection
The A1425 contains an on-chip voltage regulator and can oper-
ate over a wide supply voltage range. In applications that operate
the device from an unregulated power supply, transient protec-
tion must be added externally. For applications using a regulated
line, EMI/RFI protection may still be required. The circuit
shown in fi gure 3 is the most basic confi guration required for
proper device operation.
t
t
Figure 3. Basic application circuit. A pull-up resistor, R
with the output driver.
0.1 uF
(Required)
4
A1425
115 Northeast Cutoff
1.508.853.5000; www.allegromicro.com
Allegro MicroSystems, Inc.
Worcester, Massachusetts 01615-0036 U.S.A.
3
1
2
R
PU
PU
, is required
VCC
V
OUT
11