ACS755xCB-100: Current Sensor IC

ACS755LCB-100-PFF
Fully Integrated, Hall Effect-Based Linear Current Sensor IC
with High Voltage Isolation and a Low-Resistance Current Conductor
Last Time Buy
These parts are in production but have been determined to be
LAST TIME BUY. This classification indicates that the product is
obsolete and notice has been given. Sale of this device is currently
restricted to existing customer applications. The device should not be
purchased for new design applications because of obsolescence in the
near future. Samples are no longer available.
Date of status change: November 1, 2010
Deadline for receipt of LAST TIME BUY orders: April 30, 2011
Recommended Substitutions:
For existing customer transition, and for new customers or new applications, refer to the ACS758LCB-100U-PFF-T.
NOTE: For detailed information on purchasing options, contact your
local Allegro field applications engineer or sales representative.
Allegro MicroSystems, Inc. reserves the right to make, from time to time, revisions to the anticipated product life cycle plan
for a product to accommodate changes in production capabilities, alternative product availabilities, or market demand. The
information included herein is believed to be accurate and reliable. However, Allegro MicroSystems, Inc. assumes no responsibility for its use; nor for any infringements of patents or other rights of third parties which may result from its use.
ACS755xCB-100
Fully Integrated, Hall Effect-Based Linear Current Sensor IC
with High Voltage Isolation and a Low-Resistance Current Conductor
Features and Benefits
Description
▪ Monolithic Hall IC for high reliability
▪ Single +5 V supply
▪ 3 kVRMS isolation voltage between terminals 4/5 and
pins 1/2/3 for up to 1 minute
▪ 27 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 DC currents
The Allegro ACS755 family of current sensor ICs provides
economical and precise solutions for DC current sensing in
industrial, automotive, commercial, and communications
systems. The device package allows for easy implementation by
the customer. Typical applications include motor control, load
detection and management, power supplies, and overcurrent
fault protection.
The device consists of a precision, low-offset linear Hall
circuit with a copper conduction path located near the die.
Applied current flowing through this copper conduction path
generates a magnetic field which the Hall IC converts 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.
Package: 5 pin package (leadform PFF)
The output of the device will be valid when a current flows
through the primary copper conduction path from terminal 4
to terminal 5, which is the path used for current sampling. The
internal resistance of this conductive path is 100 μΩ typical,
providing low power loss.
Continued on the next page…
Typical Application
+5 V
4
VCC
IP+
ACS755
IP
GND
5
1
CBYP
0.1 µF
2
CF
IP–
VIOUT
3
RF
VOUT
Application 1. The ACS755 outputs an analog signal, VOUT .
that varies linearly with the unidirectional DC primary sampled
current, IP , within the range specified. CF is recommended for
noise management, with values that depend on the application.
ACS755100-DS Rev. 11
Fully Integrated, Hall Effect-Based Linear Current Sensor IC
with High Voltage Isolation and a Low-Resistance Current Conductor
ACS755xCB-100
Description (continued)
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 signal leads (pins 1 through
3). This allows the ACS755 family of sensor ICs 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 (Pb) free. All leads are plated with
100% matte tin, and there is no Pb inside the package. The heavy
gauge leadframe is made of oxygen-free copper.
Selection Guide
Part Number
TOP
(°C)
Primary
Sampled
Current, IP
(A)
Sensitivity
Sens (Typ.)
(mV/A)
Bandwidth
(kHz)
Terminals
Signal Pins
ACS755LCB-100-PFF2
–40 to 150
100
40
27
Formed
Formed
Package
Packing1
170 pieces per bulk bag
1Contact Allegro
for additional packing options.
is in production but has been determined to be LAST TIME BUY. This classification indicates that the variant is obsolete and notice has been
given. Sale of the variant is currently restricted to existing customer applications. The variant should not be purchased for new design applications
because of obsolescence in the near future. Samples are no longer available. Status date change November 1, 2010. Deadline for receipt of LAST
TIME BUY orders is April 30, 2011.
2Variant
Absolute Maximum Ratings
Characteristic
Symbol
Notes
Rating
Units
Supply Voltage
VCC
16
V
Reverse Supply Voltage
VRCC
–16
V
Output Voltage
VIOUT
16
V
Reverse Output Voltage
VRIOUT
–0.1
V
VISO
353 VAC, 500 VDC, or Vpk
V
IIN
200
A
Maximum Basic Isolation Voltage
Maximum Rated Input Current
Output Current Source
Output Current Sink
Nominal Operating Ambient Temperature
Maximum Junction
Storage Temperature
IOUT(Source)
3
mA
IOUT(Sink)
10
mA
Range L
–40 to 150
ºC
Range S
TA
–20 to 85
ºC
TJ(max)
165
ºC
Tstg
–65 to 170
ºC
TÜV America
Certificate Number:
U8V 04 11 54214 001
Fire and Electric Shock
EN60950-1:2001
Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
2
Fully Integrated, Hall Effect-Based Linear Current Sensor IC
with High Voltage Isolation and a Low-Resistance Current Conductor
ACS755xCB-100
Functional Block Diagram
+5 V
VCC
IP+
Voltage
Regulator
Filter
Dynamic Offset
Cancellation
To all subcircuits
Amp
Gain
Out
Temperature
Coefficient
VIOUT
0.1 μF
Offset
Trim Control
GND
IP–
Pin-out Diagram
IP+
IP–
4
3
VIOUT
2
GND
1
VCC
5
Terminal List Table
Number
Name
1
VCC
Device power supply pin
Description
2
GND
Signal ground pin
3
VIOUT
4
IP+
Terminal for current being sampled
5
IP–
Terminal for current being sampled
Analog output signal pin
Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
3
ACS755xCB-100
Fully Integrated, Hall Effect-Based Linear Current Sensor IC
with High Voltage Isolation and a Low-Resistance Current Conductor
ELECTRICAL CHARACTERISTICS, over operating ambient temperature range unless otherwise stated
Characteristic
Symbol
Test Conditions
Min.
Primary Sampled Current
IP
0
Supply Voltage
VCC
4.5
Supply Current
ICC
VCC = 5.0 V, output open
6.5
Output Resistance
ROUT
IOUT = 1.2 mA
–
Output Capacitance Load
CLOAD
VOUT to GND
–
VOUT to GND
4.7
Output Resistive Load
RLOAD
Primary Conductor Resistance
RPRIMARY
IP = +100A; TA = 25°C
–
Isolation Voltage
VISO
Pins 1-3 and 4-5; 60 Hz, 1 minute
3.0
PERFORMANCE CHARACTERISTICS, -20°C to +85°C, VCC = 5 V unless otherwise specified
Propagation time
tPROP
IP = +50 A, TA = 25°C
–
Response time
tRESPONSE IP = +50 A, TA = 25°C
–
Rise time
tr
IP = +50 A, TA = 25°C
–
–
Frequency Bandwidth
f
–3 dB , TA = 25°C
Over full range of IP , TA = 25°C
–
Sensitivity
Sens
Over full range of IP
36.5
Peak-to-peak, TA = 25°C,
Noise
VNOISE
–
no external filter
Linearity
ELIN
Over full range of IP
–
Zero Current Output Voltage
VOUT(Q)
I = 0 A, TA = 25°C
–
I = 0 A, TA = 25°C
–15
Electrical Offset Voltage
VOE
(Magnetic error not included)
I=0A
–25
Magnetic Offset Error
IERROM
I = 0 A, after excursion of 100 A
–
Over
full
range
of
I
,
T
=
25°C
–
Total Output Error
P
A
ETOT
(Including all offsets)
Over full range of IP
–
PERFORMANCE CHARACTERISTICS, -40°C to +150°C, VCC = 5 V unless otherwise specified
Propagation time
tPROP
IP = +50 A, TA = 25°C
–
Response time
tRESPONSE IP = +50 A, TA = 25°C
–
Rise time
tr
IP = +50 A, TA = 25°C
–
Frequency Bandwidth
f
–3 dB , TA = 25°C
–
Over full range of IP , TA = 25°C
–
Sensitivity
Sens
Over full range of IP
36
Peak-to-peak, TA = 25°C,
–
Noise
VNOISE
no external filter
Linearity
ELIN
Over full range of IP
–
I = 0 A, TA = 25°C
–
Zero Current Output Voltage
VOUT(Q)
I = 0 A, TA = 25°C
–15
Electrical Offset Voltage
VOE
(Magnetic error not included)
I=0A
–50
Magnetic Offset Error
IERROM
I = 0 A, after excursion of 100 A
–
Over full range of IP , TA = 25°C
–
Total Output Error
ETOT
(Including all offsets)
Over full range of IP
–
Typ.
–
5.0
8
1
–
–
100
–
Max.
100
5.5
10
2
10
–
–
–
Units
A
V
mA
Ω
nF
kΩ
μΩ
kV
4
13
13
27
40
–
–
–
–
–
–
41.5
μs
μs
μs
kHz
mV/A
mV/A
65
–
mV
–
0.6
–
–
±0.1
±1
–
±2.8
–
15
25
±0.30
–
±9.0
%
V
mV
mV
A
%
%
4
13
13
27
40
–
–
–
–
–
–
42
μs
μs
μs
kHz
mV/A
mV/A
65
–
mV
–
0.6
–
–
±0.1
±1
–
±2.8
–
15
50
±0.30
–
±10.0
%
V
mV
mV
A
%
%
Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
4
ACS755xCB-100
Fully Integrated, Hall Effect-Based Linear Current Sensor IC
with High Voltage Isolation and a Low-Resistance Current Conductor
Definitions of Accuracy Characteristics
Sensitivity (Sens). The change in device 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 programmed at the factory to optimize the sensitivity (mV/A) for the
full-scale current of the device.
it nominally remains at 0.6. Variation in VIOUT(Q) can be attributed
to the resolution of the Allegro linear IC quiescent voltage trim
and thermal drift.
Noise (VNOISE). The product of the linear IC amplifier gain
(mV/G) and the noise floor for the Allegro Hall effect linear IC
(≈1 G). The noise floor 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.
Magnetic offset error (IERROM). The magnetic offset is due to
the residual magnetism (remnant field) of the core material. The
magnetic 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 flux concentrator.
The larger magnetic offsets are observed at the lower operating
temperatures.
Linearity (ELIN). The degree to which the voltage output from
the IC 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 flux concentrator approaching the
full-scale current. The following equation is used to derive the
linearity:
100 1 –
VIOUT_3/4 full-scale IP – VIOUT(Q)
3 VIOUT_1/4 full-scale IP – VIOUT(Q)

Electrical offset voltage (VOE). The deviation of the device output from its ideal quiescent value due to nonmagnetic causes.
Accuracy (ETOT). The accuracy represents the maximum deviation of the actual output from its ideal value. This is also known
as the total output error. The accuracy is illustrated graphically in
the output voltage versus current chart on the following page.
Accuracy is divided into four areas:

where
 0 A at 25°C. Accuracy at the zero current flow at 25°C, without the effects of temperature.
VIOUT_¼ full-scale IP (V) is the output voltage when the sampled
current approximates 0.25  IP(max), and
VIOUT_¾ full-scale IP (V) is the output voltage when the sampled
current approximates 0.75  IP(max).
 0 A over Δ temperature. Accuracy at the zero current flow
including temperature effects.
Quiescent output voltage (VIOUT(Q)). The output of the device
when the primary current is zero. For a unipolar supply voltage,
 Full-scale current over Δ temperature. Accuracy at the fullscale current flow including temperature effects.
 Full-scale current at 25°C. Accuracy at the the full-scale current
at 25°C, without the effects of temperature.
Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
5
ACS755xCB-100
Fully Integrated, Hall Effect-Based Linear Current Sensor IC
with High Voltage Isolation and a Low-Resistance Current Conductor
Output Voltage versus Sampled Current
Accuracy at 0 A and at Full-Scale Current
Increasing VIOUT(V)
Accuracy
Over $Temp erature
Accuracy
25°C Only
Average
VIOUT
Accuracy
Over $Temp erature
Accuracy
25°C Only
–IP (A)
+IP (A)
Full Scale
IP(max)
0A
Decreasing VIOUT(V)
Definitions of Dynamic Response Characteristics
Propagation delay (tPROP). The time required for the device
output to reflect a change in the primary current signal. Propagation delay is attributed to inductive loading within the linear IC
package, as well as in the inductive loop formed by the primary
conductor geometry. Propagation delay can be considered as a
fixed time offset and may be compensated.
I (%)
90
Transducer Output
0
Propagation Time, tPROP
I (%)
Response time (tRESPONSE). The time interval between a) when
the primary current signal reaches 90% of its final value, and b)
when the device reaches 90% of its output corresponding to the
applied current.
Primary Current
t
Primary Current
90
Transducer Output
0
Response Time, tRESPONSE
Rise time (tr). The time interval between a) when the device
reaches 10% of its full scale value, and b) when it reaches 90%
of its full scale value. The rise time to a step response is used to
derive the bandwidth of the device, in which ƒ(–3 dB) = 0.35 / tr.
Both tr and tRESPONSE are detrimentally affected by eddy current
losses observed in the conductive IC ground plane.
I (%)
t
Primary Current
90
Transducer Output
10
0
Rise Time, tr
t
Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
6
ACS755xCB-100
Fully Integrated, Hall Effect-Based Linear Current Sensor IC
with High Voltage Isolation and a Low-Resistance Current Conductor
Step Response
50 A Excitation Signal, TA=25°C
x100 Device
Excitation
Signal
Output (mV)
Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
7
Fully Integrated, Hall Effect-Based Linear Current Sensor IC
with High Voltage Isolation and a Low-Resistance Current Conductor
ACS755xCB-100
Package CB, 5-pin package
Leadform PFF
0.5
R1
R3
…0.5 B
14.0±0.2
3.0±0.2
1.50±0.10
4.0±0.2
5
4
4
R2
21.4
3
1º±2°
A
3.5±0.2
…0.8
17.5±0.2
…1.5
13.00±0.10
1.91
B
Branded
Face
4.40±0.10
PCB Layout Reference View
2.9±0.2
NNNNNNN
TTT - AAA
5º±5°
1
2
+0.060
0.381 –0.030
3
10.00±0.10
3.5±0.2
LLLLLLL
YYWW
1
7.00±0.10
C Standard Branding Reference View
N = Device part number
T = Temperature code
A = Amperage range
L = Lot number
Y = Last two digits of year of manufacture
W = Week of manufacture
= Supplier emblem
0.51±0.10
1.9±0.2
For Reference Only; not for tooling use (reference DWG-9111, DWG-9110)
Dimensions in millimeters
Dimensions exclusive of mold flash, gate burrs, and dambar protrusions
Exact case and lead configuration at supplier discretion within limits shown
Creepage distance, current terminals to signal pins: 7.25 mm
Clearance distance, current terminals to signal pins: 7.25 mm
Package mass: 4.63 g typical
A Dambar removal intrusion
B Perimeter through-holes recommended
C Branding scale and appearance at supplier discretion
Copyright ©2004-2010, Allegro MicroSystems, Inc.
Allegro MicroSystems, Inc. reserves the right to make, from time to time, such departures from the detail specifications as may be required to permit improvements in the performance, reliability, or manufacturability of its products. Before placing an order, the user is cautioned to verify that the
information being relied upon is current.
Allegro’s products are not to be used in life support devices or systems, if a failure of an Allegro product can reasonably be expected to cause the
failure of that life support device or system, or to affect the safety or effectiveness of that device or system.
The information included herein is believed to be accurate and reliable. However, Allegro MicroSystems, Inc. assumes no responsibility for its use;
nor for any infringement of patents or other rights of third parties which may result from its use.
For the latest version of this document, visit our website:
www.allegromicro.com
Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
8