Current Sensor: ACS755xCB-150
5
4
The Allegro ACS75x family of current sensors provides economical and
precise solutions for current sensing in industrial, automotive, commercial, and
communications systems. The device package allows for easy implementation by
the customer. Typical applications include load detection and management, power
supplies, and overcurrent fault protection.
The device consists of a precision, low-offset linear Hall sensor circuit with a
copper conduction path located near the die. Applied current
fl
owing through
this copper conduction path generates a magnetic
fi
eld which is sensed by the
integrated Hall IC and converted into a proportional voltage. Device accuracy
is optimized through the close proximity of the magnetic signal to the Hall
transducer. A precise, proportional voltage is provided by the low-offset, chopper-
stabilized BiCMOS Hall IC, which is programmed for accuracy at the factory.
The output of the device will be valid when the current
fl
ows from pin 4 to pin 5.
The internal resistance of this conductive path is typically 100
μΩ,
providing
low power loss. The thickness of the copper conductor allows survival of the
device at up to 5× overcurrent conditions. The terminals of the conductive path
are electrically isolated from the sensor leads (pins 1 through 3). This allows the
ACS75x family of sensors to be used in applications requiring electrical isolation
without the use of opto-isolators or other costly isolation techniques.
The device is fully calibrated prior to shipment from the factory. The ACS75x
family is lead-free. All leads are coated with 100% matte tin, and there is no lead
inside the package. The heavy gauge leadframe is made of oxygen-free copper.
1
2
3
Package CB-PSF
5
4
1
2
3
Package CB-PSS
Pin 1: VCC
Pin 2: GND
Pin 3: VOUT
Terminal 4: IP+
Terminal 5: IP–
Features and Benefits
•
•
•
•
•
•
•
•
•
•
•
Monolithic Hall IC for high reliability
Single +5 V supply
3 kV
RMS
isolation voltage between terminals 4/5 and pins 1/2/3
35 kHz bandwidth
Automotive temperature range
End-of-line factory-trimmed for gain and offset
Ultra-low power loss: 100
μΩ
internal conductor resistance
Ratiometric output from supply voltage
Extremely stable output offset voltage
Small package size, with easy mounting capability
Output proportional to ac and dc currents
ABSOLUTE MAXIMUM RATINGS
Supply Voltage, V
CC
..........................................
16 V
Reverse Supply Voltage, V
RCC
........................ –16
V
Output Voltage, V
OUT
........................................
16 V
Reverse Output Voltage, V
ROUT
...................... –0.1
V
Output Current Source, I
OUT(Source)
.................
3 mA
Output Current Sink, I
OUT(Sink)
.......................10
mA
Operating Temperature,
Ambient, T
A
, K range.....................
–40 to 125ºC
Ambient, T
A
, S range .......................
–20 to 85ºC
Maximum Junction, T
J(max)
.............................
165°C
Maximum Storage Temperature, T
S
....
–65 to 170°C
Applications
• Automotive systems
• Industrial systems
• Power conversion
• Battery monitors
Use the following complete part numbers when ordering:
Part Number
TÜV America
Certificate Number:
U8V 04 11 54214 001
ACS755KCB-150-PSF
ACS755KCB-150-PSS
ACS755SCB-150-PSF
ACS755SCB-150-PSS
Package
Formed signal pins
Straight signal pins
Formed signal pins
Straight signal pins
Ambient
–40 to 125°C
–20 to 85°C
ACS755150-DS, Rev. 2
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
Current Sensor: ACS755xCB-150
Functional Block Diagram
+5 V
IP–
Terminal 5
VCC
Pin 1
Voltage
Regulator
To all subcircuits
Dynamic Offset
Cancellation
Amp
Filter
Out
VOUT
Pin 3
0.1
μF
Gain
Temperature
Coefficient
Trim Control
Offset
IP+
Terminal 4
GND
Pin 2
2
ACS755150-DS, Rev. 2
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
Current Sensor: ACS755xCB-150
ELECTRICAL CHARACTERISTICS,
over operating ambient temperature range unless otherwise stated
Characteristic
Symbol
Test Conditions
Min.
Primary Sensed Current
I
P
0
Supply Voltage
V
CC
4.5
V
CC
= 5.0 V, output open
6.5
Supply Current
I
CC
I
OUT
= 1.2 mA
–
Output Resistance
R
OUT
Output Capacitance Load
C
LOAD
VOUT to GND
–
VOUT to GND
4.7
Output Resistive Load
R
LOAD
Primary Conductor Resistance
R
PRIMARY
I
P
= +50A; T
A
= 25°C
–
Isolation Voltage
V
ISO
Pins 1-3 and 4-5; 60 Hz, 1 minute
3.0
PERFORMANCE CHARACTERISTICS, -20°C to +85°C,
V
CC
= 5 V unless otherwise specified
Propagation time
t
PROP
I
P
= +50 A, T
A
= 25°C
–
Response time
t
RESPONSE
I
P
= +50 A, T
A
= 25°C
–
I
P
= +50 A, T
A
= 25°C
–
Rise time
t
r
Frequency Bandwidth
f
–3 dB, T
A
= 25°C
–
–
Over full range of I
P
, T
A
= 25°C
Sensitivity
Sens
Over full range of I
P
24.5
Peak-to-peak, T
A
= 25°C,
Noise
V
NOISE
–
no external
fi
lter
Linearity
E
LIN
Over full range of I
P
–
Zero Current Output Voltage
V
OUT(Q)
I = 0 A, T
A
= 25°C
–
I = 0 A, T
A
= 25°C
–15
Electrical Offset Voltage
V
OE
(Magnetic error not included)
I=0A
–25
I
ERROM
I = 0 A, after excursion of 150 A
–
Magnetic Offset Error
Over full range of I
P
, T
A
= 25°C
–
Total Output Error
E
TOT
(Including all offsets)
Over full range of I
P
–
PERFORMANCE CHARACTERISTICS, -40°C to +125°C,
V
CC
= 5 V unless otherwise specified
I
P
= +50 A, T
A
= 25°C
–
Propagation time
t
PROP
Response time
t
RESPONSE
I
P
= +50 A, T
A
= 25°C
–
Rise time
t
r
I
P
= +50 A, T
A
= 25°C
–
Frequency Bandwidth
f
–3 dB, T
A
= 25°C
–
Over full range of I
P
, T
A
= 25°C
–
Sensitivity
Sens
Over full range of I
P
24
Peak-to-peak, T
A
= 25°C,
Noise
V
NOISE
–
no external
fi
lter
Linearity
E
LIN
Over full range of I
P
–
I = 0 A, T
A
= 25°C
–
Zero Current Output Voltage
V
OUT(Q)
I = 0 A, T
A
= 25°C
–15
Electrical Offset Voltage
V
OE
(Magnetic error not included)
I=0A
–40
Magnetic Offset Error
I
ERROM
I = 0 A, after excursion of 150 A
–
Over full range of I
P
, T
A
= 25°C
–
Total Output Error
E
TOT
(Including all offsets)
Over full range of I
P
–
Typ.
–
5.0
8
1
–
–
100
–
4
10
10
35
26
–
50
–
0.6
–
–
±0.1
±1.0
–
4
10
10
35
26
–
50
–
0.6
–
–
±0.1
±1.0
–
Max.
150
5.5
10
2
10
–
–
–
–
–
–
–
–
27.5
–
±0.95
–
15
25
±0.15
–
±5.0
–
–
–
–
–
28
–
±0.95
–
15
40
±0.15
–
±7.0
Units
A
V
mA
Ω
nF
kΩ
μΩ
kV
μs
μs
μs
kHz
mV/A
mV/A
mV
%
V
mV
mV
A
%
%
μs
μs
μs
kHz
mV/A
mV/A
mV
%
V
mV
mV
A
%
%
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ACS755150-DS, Rev. 2
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
Current Sensor: ACS755xCB-150
Definitions of Accuracy Characteristics
Sensitivity (Sens):
The change in sensor output in response to a 1 A change through the primary conductor. The sensitivity is the
product of the magnetic circuit sensitivity (G / A) and the linear IC amplifier gain (mV/G). The linear IC amplifier gain is trimmed at the
factory to optimize the sensitivity (mV/A) for the full-scale current of the device.
Noise (V
NOISE
):
The product of the linear IC amplifier gain (mV/G) and the noise
fl
oor for the Allegro Hall effect linear IC (≈1 G).
The noise
fl
oor is derived from the thermal and shot noise observed in Hall elements. Dividing the noise (mV) by the sensitivity
(mV/A) provides the smallest current that the device is able to resolve.
Linearity (E
LIN
):
The degree to which the voltage output from the sensor varies in direct proportion to the primary current through its
full-scale amplitude. Nonlinearity in the output can be attributed to the saturation of the
fl
ux concentrator approaching the full-scale
current. The following equation is used to derive the linearity:
1–
V
out _
3
/
4
full-scale I
P
–V
OUT(Q)
3
V
out _
1
/
4
full-scale I
P
–V
OUT(Q)
Nonlinearity (%) = 100
where
‰
Vout_¼
full-scale I
P
(V) is the output voltage when the sensed current approximates 0.25
×
I
P(max)
, and
Vout_¾
full-scale I
P
(V) is the output voltage when the sensed current approximates 0.75
×
I
P(max)
.
Quiescent output voltage (V
OUT(Q)
):
The output of the sensor when the primary current is zero. For a unipolar supply voltage, it
nominally remains at 0.6 V. Variation in V
OUT(Q)
can be attributed to the resolution of the Allegro linear IC quiescent voltage trim,
magnetic hysteresis, and thermal drift.
Electrical offset voltage (V
OE
):
The deviation of the device output from its ideal quiescent value due to nonmagnetic causes.
Magnetic offset error (I
ERROM
):
The magnetic offset is due to the residual magnetism (remnant
fi
eld) of the core material. The mag-
netic offset error is highest when the magnetic circuit has been saturated, usually when the device has been subjected to a full-scale or
high-current overload condition. The magnetic offset is largely dependent on the material used as a
fl
ux concentrator. The larger mag-
netic offsets are observed at the lower operating temperatures.
Accuracy (E
TOT
):
The accuracy represents the maximum deviation of the actual output from its ideal value. This is also known as the
total ouput error. The accuracy is illustrated graphically in the Output Voltage versus Current chart on the following page.
Accuracy is divided into four areas:
•
0 A at 25°C:
Accuracy of sensing zero current
fl
ow at 25°C, without the effects of temperature.
•
0 A over temperature:
Accuracy of sensing zero current
fl
ow including temperature effects.
•
Full-scale current at 25°C:
Accuracy of sensing the full-scale current at 25°C, without the effects of temperature.
•
Full-scale current over
Δ
temperature:
Accuracy of sensing full-scale current
fl
ow including temperature effects.
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ACS755150-DS, Rev. 2
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
Current Sensor: ACS755xCB-150
Output voltage vs. current, illustrating sensor accuracy at 0 A and at full-scale current
Increasing V
OUT
(V)
Accuracy
Over
ΔTemperature
Accuracy
25°C Only
Average
V
OUT
Accuracy
Over
ΔTemperature
Accuracy
25°C Only
–I
P
(A)
150 A
0A
+I
P
(A)
Full Scale
Decreasing V
OUT
(V)
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ACS755150-DS, Rev. 2
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000