A1126LLHLT-T Allegro Microsystems Inc, A1126LLHLT-T Datasheet - Page 11

• Manufacturer Part Number: A1126LLHLT-T
• Description: IC SW HALL EFFECT OMNI SOT23W
• Manufacturer: Allegro Microsystems Inc
• Series: -r
• Type: Omnipolar Switchr

Specifications of A1126LLHLT-T

• Sensing Range: ±55G Trip, ±50G Release
• Voltage - Supply: 3 V ~ 24 V
• Current - Supply: 4mA
• Current - Output (max): -
• Output Type: Digital, Open Drain
• Features: Ultra Sensitive
• Operating Temperature: -40°C ~ 150°C
• Package / Case: *
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 620-1421-2

A1126
The device must be operated below the maximum junction
temperature of the device, T
tions of peak conditions, reliable operation may require derating
supplied power or improving the heat dissipation properties of
the application. This section presents a procedure for correlating
factors affecting operating T
the Allegro MicroSystems Web site.)
The Package Thermal Resistance, R
marizing the ability of the application and the device to dissipate
heat from the junction (die), through all paths to the ambient air.
Its primary component is the Effective Thermal Conductivity,
K, of the printed circuit board, including adjacent devices and
traces. Radiation from the die through the device case, R
relatively small component of R
T
overmolding.
The effect of varying power levels (Power Dissipation, P
be estimated. The following formulas represent the fundamental
relationships used to estimate T

For example, given common conditions such as: T
V

A worst-case estimate, P
able power level, without exceeding T
and T
A
Subject to Change Without Notice
IN
, and air motion are significant external factors, damped by
Preliminary Datasheet
= 12 V, I

A
.
May 3, 2011
T = P
IN
P
= 4 mA, and R
D
T
= V
D
J
= T
×
IN
T = P
P
A
R
T
×
D
D
JA
J
+ T = 25°C + 7°C = 32°C
(max) , represents the maximum allow-
= V
= T
I
IN
J
J
= 48 mW
(max) . Under certain combina-
. (Thermal data is also available on
D
IN
A
= 12 V
JA
×
J
+ ΔT
JA
, at P
×
R
= 140 °C/W, then:
I
. Ambient air temperature,
JA
IN
JA
D
×
Chopper-Stabilized Omnipolar Hall-Effect Switch
J
×
.
(max) , at a selected R
, is a figure of merit sum-
4 mA = 48 mW
140 °C/W = 7°C
A
= 25°C,
Power Derating
JC
D
), can
(2)
(3)
, is
(1)
JA
Example: Reliability for V
single-layer PCB.
Observe the worst-case ratings for the device, specifically:
R
I
Calculate the maximum allowable power level, P
invert equation 3:
This provides the allowable increase to T
power dissipation. Then, invert equation 2:
Finally, invert equation 1 with respect to voltage:
The result indicates that, at T
dissipate adequate amounts of heat at voltages ≤V
Compare V
reliable operation between V
enhanced R
between V
tions.
CC
JA
V
T
(max) = 4 mA.
CC
P
= 165 °C/W, T
max
(est) = P
D
(max) = T
= T
CC
CC
JA
(est) and V
J
(est) to V
(max) – T
. If V
D
(max) ÷ I
J
(max) = 165°C, V
CC
max
(est) ≥ V
CC
CC
A
÷ R
CC
CC
(max) . If V
115 Northeast Cutoff
1.508.853.5000; www.allegromicro.com
Allegro MicroSystems, Inc.
Worcester, Massachusetts 01615-0036 U.S.A.
= 165 °C – 150 °C = 15 °C
(max) is reliable under these condi-
JA
(max) = 91 mW ÷ 4 mA = 23 V
A
CC
at T
, the application and device can
(est) and V
= 15°C ÷ 165 °C/W = 91 mW
CC
A
= 150°C, package UA, using a
(max) , then operation
CC
CC
(max) = 24 V, and
(est) ≤ V
J
resulting from internal
CC
(max) requires
D
CC
CC
(max) . First,
(est) .
(max) , then
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