A1425_16 Datasheet, PDF (4/13 Pages) Allegro MicroSystems – High Accuracy Analog Speed Sensor IC with Integrated Filter

A1425
High Accuracy Analog Speed Sensor IC with Integrated
Filter Capacitor and Dual Zero-Crossing Output Signal
THERMAL CHARACTERISTICS may require derating at maximum conditions, see application information
Characteristic
Symbol
Test Conditions
Rating Units
Package Thermal Resistance
R_θJA
Single-layer PCB, with copper limited to solder pads
177 ºC/W
Power Derating Curve
30
28
26
V_CC(max)
24
22
20
18
16
(R_θJA = 177 ºC/W)
14
12
10
8
6
4
V_CC(min)
2
0
20 40 60 80 100 120 140 160 180
Temperature (ºC)
900
850
800
750
700
650
600
550
500
450
400
350
300
250
200
150
100
50
0
20
Maximum Power Dissipation, P_D(max)
(R
θ_{JA = 177 ºC/W)}
40
60
80
100
120
140
160
180
Temperature (°C)
Definitions of Terms
The following provide additional information about some of
the parameters cited in the Operating Characteristics table.
For additional information, visit the Allegro Web site at
www.allegromicro.com.
Applied Magnetic Field, B_diff – The differential magnetic flux
density which is calculated as the arithmetic difference of the
flux densities observed by each of the two Hall elements.
Output Off Switchpoint (Operate Point), B_OP – The value of
increasing differential magnetic flux density at which the device
output switches from low to high. This value may be greater than
or less than 0 G.
Output On Switchpoint (Release Point), B_RP – The value of
decreasing differential magnetic flux density at which the device
output switches from high to low. This value may be greater
than or less than 0 G.
Power-On Time, t_PO – The time needed by the device, after
power is applied, to initialize all circuitry necessary for proper
operation.
Settling Time, t_Settle – The time required by the device, after t_PO,
and after a valid magnetic signal has been applied, to provide
proper output transitions. Settling time is a function of magnetic
offset, offset polarity, signal phase, signal frequency, and signal
amplitude.
Response Time t_Response – The total time required for generat-
ing zero-crossing output transitions after power-up (the sum of
power-on time and settling time).
Allegro MicroSystems, LLC
4
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com