MAX9621_V01 [MAXIM]
Dual, 2-Wire Hall-Effect Sensor Interface with Analog and Digital Outputs;
| 型号： | MAX9621_V01 |
| 厂家： | 
MAXIM INTEGRATED PRODUCTS |
| 描述： | Dual, 2-Wire Hall-Effect Sensor Interface with Analog and Digital Outputs |
| 文件： | 总16页 (文件大小：1265K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
EVALUATION KIT AVAILABLE
Click here for production status of specific part numbers.
MAX9621
Dual, 2-Wire Hall-Effect Sensor Interface
with Analog and Digital Outputs
General Description
Features
The MAX9621 is a continuation of the Maxim family of
Hall-effect sensor interfaces that already includes the
MAX9921. The MAX9621 provides a single-chip solution
to interface two 2-wire Hall-effect sensors to low-voltage
microprocessors (µP) through either a digital output for
Hall-effect switches or an analog output for linear informa-
tion or both.
● Provides Supply Current and Interfaces to Two
2-Wire Hall-Effect Sensors
● 5.5V to 18V Operating Voltage Range
● Protects Hall Sensors Against Up to 60V Supply
Transients
● Low-Power Shutdown for Power Saving
● Filtered Digital Outputs
The MAX9621 protects the Hall sensors from supply
transients up to 60V at the BAT supply. Normal operating
supply voltage ranges from 5.5V to 18V. If the BAT supply
rises above 18V, the MAX9621 shuts off the current to
the Hall sensors. When a short-to-ground fault condition
is detected, the current to the Hall input is shut off and
the condition is indicated at the analog output by a zero-
current level and a high digital output.
● Analog Output Mirrors the Hall Sensor Current
● Hall Inputs Protected from Short to Ground
● Hall Sensor Blanking Following Power-Up and
Restart from Shutdown and Short to Ground
● Operates with ±3V Ground Shift Between the Hall
Sensor and the MAX9621
● ±2kV Human Body Model ESD and ±200V Machine
The MAX9621 provides a minimum of 50µs blanking time
following Hall sensor power-up or restart. The open drain-
digital outputs are compatible with logic levels up to 5.5V.
Model ESD at All Pins
● 3mm x 5mm, 10-Pin μMAX Package
The MAX9621 is available in a 3mm x 5mm, 10-pin
µMAX package and is rated for operation in the -40ºC to
Functional Diagram
®
+125ºC temperature range.
BAT
REF
Applications
REFERENCE
ISET
BAT
SLEEP-MODE
CONTROL
SLEEP
● Window Lifters
● Seat Movers
10k
Ω
● Electric Sunroofs
● Seatbelt Buckles
● Door Power Locks
● Ignition Key
AOUT1
DOUT1
IN1
FILTER
REF
● Steering Column
● Speed Sensing
BAT
INPUT
SHORT
MAX9621
DETECTION
Ordering Information
AOUT2
DOUT2
PART
TEMP RANGE
-40ºC to +125ºC
-40ºC to +125ºC
PIN-PACKAGE
10 µMAX
IN2
MAX9621AUB+T
MAX9621AUB/V+
FILTER
REF
10 µMAX
+Denotes a lead(Pb)-free/RoHS-compliant package.
T = Tape and reel.
GND
/V denotes an automotive qualified part.
Typical Application Circuit appears at end of data sheet.
μMAX is a registered trademark of Maxim Integrated Products, Inc.
19-5024; Rev 2; 2/20
MAX9621
Dual, 2-Wire Hall-Effect Sensor Interface
with Analog and Digital Outputs
Absolute Maximum Ratings
BAT to GND...........................................................-0.3V to +60V
Continuous Power Dissipation for a Single-Layer Board
ISET to BAT..........................................................-2.0V to +0.3V
(T = +70ºC)
A
IN1, IN2 to GND................ -3V to lower of +60V or (V
AOUT1, DOUT1, AOUT2, DOUT2,
+ 1V)
10-Pin μMAX (derate 5.6mW/ºC) above +70ºC .......444.4mW
Continuous Power Dissipation for a Multilayer Board
BAT
SLEEP to GND....................................................-0.3V to +6V
Short-Circuit Duration
AOUT1, DOUT1, AOUT2, DOUT2 to GND
or to 5.5V (individually)........................................Continuous
Current In to IN1, IN2.....................................................±100mA
Current In to Any Other Pin..............................................±20mA
(T = +70ºC)
A
10-Pin μMAX (derate 8.9mW/ºC) above +70ºC .......715.6mW
Operating Temperature Range..........................-40ºC to +125ºC
Junction Temperature......................................................+150ºC
Storage Temperature Range.............................-65ºC to +160ºC
Lead Temperature (soldering, 10s) .................................+300ºC
Soldering Temperature (reflow).......................................+260ºC
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these
or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect
device reliability.
Package Information
PACKAGE TYPE: 10 µMAX
Package Code
U10+2
Outline Number
21-0061
90-0330
Land Pattern Number
THERMAL RESISTANCE, FOUR-LAYER BOARD:
Junction to Ambient (θ
)
112°C/W
37°C/W
JA
Junction to Case (θ
)
JC
For the latest package outline information and land patterns (footprints), go to www.maximintegrated.com/packages. Note that a “+”,
“#”, or “-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing
pertains to the package regardless of RoHS status.
Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-layer board.
For detailed information on package thermal considerations, refer to www.maximintegrated.com/thermal-tutorial.
Maxim Integrated
│ 2
www.maximintegrated.com
MAX9621
Dual, 2-Wire Hall-Effect Sensor Interface
with Analog and Digital Outputs
Package Information (continued)
For the latest package outline information and land patterns (footprints), go to www.maximintegrated.com/packages. Note that a “+”,
“#”, or “-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing
pertains to the package regardless of RoHS status.
Maxim Integrated
│ 3
www.maximintegrated.com
MAX9621
Dual, 2-Wire Hall-Effect Sensor Interface
with Analog and Digital Outputs
DC Electrical Characteristics
(V
= 13.6V, V
= 5V, IN1 = IN2 = no connection, R
= 61.9kΩ to BAT, R
= 10kΩ at DOUT1 and DOUT2, R = 5kΩ to
PU L
BAT
SLEEP
SET
GND at AOUT1 and AOUT2, unless otherwise noted, T = -40ºC to +125ºC. Typical values are at T = +25ºC.) (Note 1)
A
A
PARAMETER
GENERAL
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
Guaranteed by functional test of I , I ,
IH IL
BAT Supply Range
BAT Supply Current
V
5.5
18
V
BAT
and G
EI
I
Normal mode
1
mA
µA
BAT
I
V
V
V
= 0V
1
10
SD
SLEEP
= 5.5V, at IN1 and IN2, I = -14mA
0.59
0.86
±200
±2000
1.26
BAT
BAT
IN
Hall Input Voltage Dropout
ESD Protection
V
V
V
DO
= 5.5V, at IN1 and IN2, I = -20mA
1.86
IN
Machine Model
Human Body Model
INPUT THRESHOLDS FOR DOUT1, DOUT2 SWITCHING
R
R
R
R
= 95.3kΩ
= 52.3kΩ
= 95.3kΩ
= 52.3kΩ
-7.7
-14
Input Current for Output High
(Note 2)
SET
SET
SET
SET
I
mA
mA
%
IH
-5
-9
Input Current for Output Low
(Note 2)
I
IL
Input Current Hysteresis for
High/Low Detection
Peak-to-peak as percent of average high/
low threshold (Note 2)
I
8
IN_HYS
High threshold
Low threshold
0.02
0.02
Channel-to-Channel Input
Threshold Variation
mA
A short to GND is not a sustained
condition, Hall input reverts to -50µA when
detected (Note 2)
Short-Circuit Current Limit
I
-20
mA
SC
AOUT1, AOUT2 ANALOG OUTPUTS
Current Gain for AOUT1 and
AOUT2 Outputs
G
-18mA ≤ I ≤ -2mA
0.05
0.2
mA/mA
%
I
IN
Current Gain Error for AOUT1
and AOUT2 Outputs
G
I
= -5mA, -14mA
±1.7
EI
IN
Inferred from measurements at
Input Referred Current Offset
I
-120
+120
µA
OS
I
= -5mA, -14mA
IN
I
I
= -14mA
= -20mA
0.85
1.09
500
1.6
V
= 5.5V, for 5%
IN
BAT
AOUT_ Dropout Voltage
V
current reduction
1.75
IN
AOUT_ Output Impedance
MΩ
LOGIC I/O (DOUT1, DOUT2)
Output-Voltage Low DOUT1,
DOUT2
V
Sink current = 1mA
0.4
±1
V
OL
Three-State Output Current
DOUT1, DOUT2
I
V
= 0V, 0V ≤ V
≤ 5V
µA
OZ
SLEEP
DOUT_
Maxim Integrated
│ 4
www.maximintegrated.com
MAX9621
Dual, 2-Wire Hall-Effect Sensor Interface
with Analog and Digital Outputs
DC Electrical Characteristics (continued)
(V
= 13.6V, V
= 5V, IN1 = IN2 = no connection, R
= 61.9kΩ to BAT, R
= 10kΩ at DOUT1 and DOUT2, R = 5kΩ to
PU L
BAT
SLEEP
SET
GND at AOUT1 and AOUT2, unless otherwise noted, T = -40ºC to +125ºC. Typical values are at T = +25ºC.) (Note 1)
A
A
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
SLEEP
Input-Voltage High
V
2.0
50
V
V
IH
Input-Voltage Low
V
0.8
IL
Input Resistance to GND
AC TIMING CHARACTERISTICS
R
100
40
kΩ
IN
Shutdown Delay from SLEEP
Low to IN_ Shutoff
I
= -14mA to GND, time from SLEEP low
IH
t
33
76
46
µs
µs
SHDN
to IN_ drop 500mV, C = 20pF
L
I
V
= -14mA to GND, time from
IH
IN_, Blanking Time at Hall
Sensor Power-Up
t
= 500mV until DOUT_ high, C =
89
103
BL
IN_
L
20pF (Notes 2, 3)
IN_, Current Ramp Rate After
Turn-On
t
IN_ = GND (Note 2)
3.6
5
6.7
16
mA/µs
µs
RAMP
Delay from IN_ to DOUT_
(Filter Delay)
From I to I or from I to I ,
IH IL IL IH
t
10.8
13.5
DEL
C = 20pF, Figure 1 (Note 2)
L
Delay Difference Between
Rising and Falling Edges of Both
Channels
C
= 0.01µF, I = -11.5mA
IH
HALL-BYPASS
t
1
µs
DM
and I = -7.5mA, C = 20pF
IL
L
Delay Difference Between
Channels
C
= 0.01µF, I = -11.5mA
HALL-BYPASS IH
t
500
39
ns
kHz
mA
µs
CC
and I = -7.5mA, C = 20pF
IL
L
Maximum Frequency on Hall
Inputs
C
= 0.01µF, I = -11.5mA
HALL-BYPASS IH
f
34
MAX
MAO
and I = -7.5mA, C = 20pF (Note 2)
IL
L
Maximum Analog Output Current
During Short-to-GND Fault
I
-1.4
11.5
IN_ Pulse Length Rejected by
Filter to DOUT_
P
Figure 2 (Note 2)
7.8
14.6
R
Note 1: All DC specifications are 100% production tested at T = +25°C. AC specifications are guaranteed by design at T = +25°C.
A
A
Note 2: Parameters that change with the value of the R
resistor: I , I , I
, I , t , t
, t
, f
, and P .
SET
IH IL IN_HYS SC BL RAMP DEL MAX
R
Note 3: Following power-up or startup from sleep mode, the start of the blanking period is delayed 20µs.
Maxim Integrated
│ 5
www.maximintegrated.com
MAX9621
Dual, 2-Wire Hall-Effect Sensor Interface
with Analog and Digital Outputs
Timing Diagrams
APPROXIMATELY 100mA
HALL SENSOR
OPEN
SHORT CIRCUIT
APPROXIMATELY 100mA
14mA
5mA/µs
IN1
7mA
0mA
APPROXIMATELY 1.4mA
RESTART
HALL SENSOR OPEN
0.7mA
AOUT1
DOUT1
5mA/µs
0.35mA
0mA
t
DEL
t
DEL
5V
0V
Figure 1. Timing Diagram
P
P
R
R
14mA
IN_
7mA
0mA
t
DEL
t
DEL
5V
0V
DOUT_
Figure 2. Hall Input Pulse Rejection
Maxim Integrated
│ 6
www.maximintegrated.com
MAX9621
Dual, 2-Wire Hall-Effect Sensor Interface
with Analog and Digital Outputs
Typical Operating Characteristics
(V
= 13.6V, R
= 61.9kΩ, R = 5kΩ to GND at AOUT_, V
= 5V, T = +25ºC, unless otherwise noted.)
BAT
SET
L
SLEEP A
BAT SUPPLY CURRENT
vs. V IN OPERATING MODE
BAT SUPPLY CURRENT
vs. V IN OPERATING MODE
BAT SUPPLY CURRENT
vs. V IN OPERATING MODE
BAT
BAT
BAT
0.9
0.9
0.8
0.7
0.6
0.5
0.4
0.9
0.8
0.7
0.6
0.5
0.4
T
A
= -40ºC
T
A
= +25ºC
T = +125ºC
A
0.8
0.7
0.6
0.5
0.4
19.0
19.5
20.0
20.5
21.0
19.0
19.5
20.0
20.5
21.0
19.0
19.5
20.0
20.5
21.0
BAT VOLTAGE (V)
BAT VOLTAGE (V)
BAT VOLTAGE (V)
BAT SUPPLY CURRENT
vs. V IN OPERATING MODE
BAT SUPPLY CURRENT
vs. V IN OPERATING MODE
BAT SUPPLY CURRENT
vs. V IN OPERATING MODE
BAT
BAT
BAT
1.0
0.8
0.6
0.4
0.2
1.0
0.8
0.6
0.4
0.2
1.0
0.8
0.6
0.4
0.2
T
A
= -40ºC
T = +25ºC
A
TA = +125ºC
0
10
20
30
40
50
60
0
10
20
30
40
50
60
0
10
20
30
40
50
60
BAT VOLTAGE (V)
BAT VOLTAGE (V)
BAT VOLTAGE (V)
BAT SUPPLY CURRENT
HALL INPUT CURRENT THRESHOLDS
FOR HIGH/LOW vs. TEMPERATURE
HALL INPUT CURRENT
vs. V
IN SHUTDOWN MODE
THRESHOLDS vs. V
BAT
BAT
200
180
160
140
120
100
80
10.50
10.25
10.00
9.75
9.50
9.25
9.00
8.75
8.50
10.4
10.2
10.0
9.8
T
A
= +125°C
LOW TO HIGH
LOW TO HIGH
9.6
9.4
60
HIGH TO LOW
9.2
40
T
A
= +25°C AND -40°C
9.0
HIGH TO LOW
20
0
8.8
5.5
8.0
10.5
13.0
15.5
18.0
0
20
40
BAT VOLTAGE (V)
60
80
-40 -25 -10
5
20 35 50 65 80 95 110 125
BAT VOLTAGE (V)
TEMPERATURE (°C)
Maxim Integrated
│
7
www.maximintegrated.com
MAX9621
Dual, 2-Wire Hall-Effect Sensor Interface
with Analog and Digital Outputs
Typical Operating Characteristics (continued)
(V
= 13.6V, R
= 61.9kΩ, R = 5kΩ to GND at AOUT_, V
= 5V, T = +25ºC, unless otherwise noted.)
BAT
SET
L
SLEEP A
INPUT BLANKING TIME AT RESTART
FROM SLEEP MODE (OR POWER-UP)
vs. TEMPERATURE
HALL INPUT CURRENT THRESHOLDS
vs. ISET RESISTOR
IN-CURRENT RAMP RATE AFTER
TURN-ON vs. TEMPERATURE
16
100
95
90
85
80
75
70
65
60
10
9
14
12
10
8
8
7
LOW TO HIGH
HIGH TO LOW
6
5
4
6
3
4
2
50
60
70
80
90
100
-40 -25 -10
5
20 35 50 65 80 95 110 125
-40 -25 -10
5
20 35 50 65 80 95 110 125
RESISTANCE (kΩ)
TEMPERATURE (°C)
TEMPERATURE (°C)
DELAY FROM IN_ TO DOUT_ (FILTER DELAY)
vs. TEMPERATURE
DELAY DIFFERENCE BETWEEN CHANNELS
vs. TEMPERATURE
MAXIMUM FREQUENCY ON
HALL INPUTS vs. TEMPERATURE
20
900
60
50
40
30
20
10
700
500
300
100
-100
15
10
5
IN1
IN2
0
-50 -25
0
25
50
75 100 125
-50 -25
0
25
50
75 100 125
-50 -25
0
25
50
75 100 125
TEMPERATURE (ºC)
TEMPERATURE (ºC)
TEMPERATURE (ºC)
INPUT DROPOUT VOLTAGE
vs. V
IN_ PULSE LENGTH REJECTED BY FILTER
TO DOUT_ vs. TEMPERATURE
INPUT DROPOUT VOLTAGE
vs. TEMPERATURE
BAT
1.15
1.05
0.95
0.85
0.75
0.65
0.55
0.45
0.35
0.25
20
1.15
1.05
0.95
0.85
0.75
0.65
0.55
0.45
0.35
0.25
I
= -14mA
IN1
V
= 5.5V
= -14mA
BAT
18
16
14
12
10
8
I
IN1
T
= +125°C
A
NEGATIVE PULSE
POSITIVE PULSE
T
= +25°C
A
6
T
= -40°C
A
4
2
0
18.00
5.50
8.00
10.50 13.00
(V)
15.50
-50 -25
0
25
50
75 100 125
-45 -25 -10
5
20 35 50 65 80 95 110 125
V
TEMPERATURE (ºC)
TEMPERATURE (°C)
BAT
Maxim Integrated
│ 8
www.maximintegrated.com
MAX9621
Dual, 2-Wire Hall-Effect Sensor Interface
with Analog and Digital Outputs
Typical Operating Characteristics (continued)
(V
= 13.6V, R
= 61.9kΩ, R = 5kΩ to GND at AOUT_, V = 5V, T = +25ºC, unless otherwise noted.)
SLEEP A
BAT
SET
L
CURRENT GAIN vs. SUPPLY VOLTAGE
CURRENT GAIN vs. TEMPERATURE
0.07
0.06
0.05
0.04
0.03
0.07
0.06
0.05
0.04
0.03
-50 -25
0
25
50
75 100 125
5.50
TEMPERATURE (ºC)
SUPPLY VOLTAGE (V)
REENERGIZING OF THE HALL INPUT
RESPONSE TO SHORT TO GROUND
FROM OPEN-CIRCUIT CONDITION
MAX9621 toc21
MAX9621 toc22
V
V
IN1
AOUT1
V
IN1
V
DOUT1
I
IN1
I
IN1
V
AOUT1
400ns/div
100µs/div
STARTUP OF IN_/AOUT_
STARTUP OF IN_/DOUT_
FROM SHUTDOWN
FROM SHUTDOWN
MAX9621 toc23
MAX9621 toc24
V
V
V
V
SLEEP
IN1
SLEEP
IN1
I
I
IN1
IN1
V
AOUT1
V
DOUT1
10µs/div
20µs/div
Maxim Integrated
│ 9
www.maximintegrated.com
MAX9621
Dual, 2-Wire Hall-Effect Sensor Interface
with Analog and Digital Outputs
Pin Configuration
TOP VIEW
+
BAT
ISET
IN1
1
2
3
4
5
10
9
SLEEP
AOUT1
DOUT1
AOUT2
DOUT2
MAX9621
8
IN2
7
GND
6
µMAX
Pin Description
PIN
NAME
FUNCTION
Battery Power Supply. Connect to the positive supply through an external reverse-polarity diode. Bypassed
to GND with a 0.1µF capacitor.
1
BAT
Current Setting Input. Place a 1% resistor (R
) between BAT and ISET to set the desired input current
SET
threshold range for the DOUT_ outputs. See the Typical Operating Characteristics section for the correct
2
3
ISET
IN1
value of R for the desired range. Make no other connections to this pin. All routing must have low
SET
parasitic capacitance. See the Input Current Thresholds and Short to Ground section.
Hall-Effect Sensor Input 1. Supplies current to the Hall sensor and monitors the current level drawn to
determine the high/low state of the sensor. Bypass to GND with a 0.01µF capacitor. Connect an unused
input to BAT pin.
Hall-Effect Sensor Input 2. Supplies current to the Hall sensor and monitors the current level drawn to
determine the high/low state of the sensor. Bypass to GND with a 0.01µF capacitor. Connect an unused
input to BAT pin.
4
5
IN2
GND
Ground
Maxim Integrated
│ 10
www.maximintegrated.com
MAX9621
Dual, 2-Wire Hall-Effect Sensor Interface
with Analog and Digital Outputs
Pin Description (continued)
PIN
NAME
FUNCTION
Open-Drain Output. Signal translated from Hall sensor 2. DOUT2 is high when the current flowing out of
6
DOUT2 IN2 exceeds the input current threshold high, and is low when less than the input current threshold low. See
Table 1 for output response to operating conditions.
Analog Current Output. Mirrors the current to the corresponding Hall sensor at IN2. When IN2 has been
AOUT2 shut down due to a short to GND a current of zero is supplied to AOUT2. See Table 1 for output response to
operating conditions. To obtain a voltage output, connect a resistor from AOUT_ to ground.
7
8
9
Open-Drain Output. Signal translated from Hall sensor 1. DOUT1 is high when the current flowing out of
DOUT1 IN1 exceeds the input current threshold high, and is low when less than the input current threshold low. See
Table 1 for output response to operating conditions.
Analog Current Output. Mirrors the current to the corresponding Hall sensor at IN1. When IN1 has been
AOUT1 shut down due to a short to GND a current of zero is supplied to AOUT1. See Table 1 for output response to
operating conditions. To obtain a voltage output, connect a resistor from AOUT_ to ground.
Sleep Mode Input. The part is placed in sleep mode when the SLEEP input is low for more than 40µs. If the
SLEEP input is low for less than 20µs and then goes high, the part restarts any Hall input that has been shut
off due to a detected short to GND. Any Hall input that is operational is not affected when SLEEP is cycled
10
SLEEP
low for less than 20µs. There is an internal 100kΩ pulldown resistance to GND.
respectively, is lower than the low-input current threshold.
DOUT1 and DOUT2 provide a time domain output filter
for robust noise immunity. See Figure 2.
Detailed Description
The MAX9621, an interface between two 2-wire Hall-
effect sensors and a low-voltage microprocessor, supplies
and monitors current through IN1 and IN2 to two Hall
sensors.
The analog outputs (AOUT1 and AOUT2) mirror the cur-
rent flowing out to the corresponding inputs IN1 and IN2
with a nominal gain of 0.05mA/mA.
The MAX9621 complements Maxim’s existing family of
Hall-effect sensor interfaces that includes the MAX9921.
Hall Sensor Protection
from Supply Transients
The MAX9621 protects the hall sensors from supply
transients by shutting off current at IN1 and IN2 when the
BAT voltage is 18V. The digital outputs go low and analog
The MAX9621 provides two independent channels with
two outputs for each channel, a digital output, and an
analog output. The digital outputs (DOUT1 and DOUT2)
are open-drain and indicate a logic level that corresponds
to the Hall sensor status. DOUT1 or DOUT2 outputs high
when the current out of IN1 or IN2, respectively, exceeds
the high-input current threshold. DOUT1 or DOUT2
outputs low when the current flowing out of IN1 or IN2,
outputs have zero output current. When V
returns to
BAT
the proper operating range, both inputs restart following
a blanking cycle.
Maxim Integrated
│ 11
www.maximintegrated.com
MAX9621
Dual, 2-Wire Hall-Effect Sensor Interface
with Analog and Digital Outputs
external capacitance of 0.02μF without tripping into a
short-to-ground latched state. During the short-to-ground
fault, DOUT1 and DOUT2 are high impedance (pulled
high by the pullup resistors), while AOUT1 and AOUT2
are set to zero-output current.
Table 1. AOUT_/DOUT_ Truth Table
CONDITION
IN_ Short to GND
AOUT_
DOUT_
High-Z
Low*
0
0
0
0
IN_ Short to BAT or IN_ Open
SLEEP Low
High-Z
Low*
Manual Method for Reenergizing Hall
Sensor and Means for Diagnosing an
Intermittent Hall Sensor Connection
V
> 18V
BAT
*If IN_ is already shorted to BAT or open during power-up,
DOUT_ goes to high-Z until IN_ is loaded.
Figure 3 shows the behavior of the MAX9621 when a
Hall input is open. Figure 4 shows the behavior of the
MAX9621 when the open input is reconnected to a Hall
sensor. Figures 3 and 4 demonstrate how a short-to-
ground Hall input can be reset. Resetting a short-to-
ground Hall input involves three steps:
Hall Input Short-to-Battery Condition
The MAX9621 interprets a short to battery when the volt-
age at IN1 or IN2 is higher than V
- 100mV. The digital
BAT
outputs go low and the analog outputs are set to zero
output current. If IN1 or IN2 is more than 1V above V
it back-drives current into BAT. The MAX9621 restarts the
Hall inputs when the Hall input is loaded again.
,
BAT
1) Relieve the short to ground at the Hall sensor.
2) Disconnect the Hall input from the Hall sensor (open-
input fault condition).
Hall Input Short to Ground
3) Reconnect the Hall input to the Hall sensor.
The Hall input short-to-ground fault is effectively a latched
condition if the input remains loaded by the Hall switch.
The current required to power the Hall switch is shut off
and only a 50μA pullup current remains. The Hall input
can be manually reenergized or it can be reenergized by
the μP. A 10μs to 20μs negative pulse at SLEEP restarts
with a blanking cycle any Hall input that has been shut
down due to the short-to-ground condition. During startup
or restart, it is possible for a Hall input to charge up an
The MAX9621 restarts the Hall input with a blanking
cycle. If the Hall input is disconnected from the Hall sen-
sor for 10ms, it allows the Hall input to be pulled up by
the 50µA pullup current to register the open-input fault
condition. Reconnecting the Hall input to the Hall sensor
restarts the Hall input with a blanking cycle. This provides
a manual means of reenergizing a Hall input without hav-
ing to resort to the µP to restart it. This also demonstrates
the behavior of an intermittent connection to a Hall sensor.
14V
V
- 25mV
BAT
HALL INPUT
SHORT-TO-
5mV/ms
V
IN_
HALL INPUT
GROUND FAULT
OPEN-CIRCUIT
FAULT
0V
TIME
HALL INPUT
DISCONNECTED
FROM SENSOR
50µA
0A
I
IN_
TIME
Figure 3. Hall Input Ramps to Open-Circuit Fault When a Short to Ground Is Relieved
Maxim Integrated
│ 12
www.maximintegrated.com
MAX9621
Dual, 2-Wire Hall-Effect Sensor Interface
with Analog and Digital Outputs
V
- 25mV
BAT
14V
V
IN_
8V
V
- 500mV
BAT
0V
11.5mA
TIME
I
IN_
5mA/µs
HALL INPUT RECONNECTED
TO HALL SENSOR
0A
TIME
Figure 4. Hall Input Reenergized When Open Input Is Reconnected to Hall Sensor
1
Sleep Mode Input (SLEEP)
I = I
+
I < 0
(
)
0
R × m
The MAX9621 features an active-low SLEEP input. Pull
I is the mean of the threshold current limits, R is the value
of the R resistance in kΩ, the constant I = 0.03717mA,
and the constant m = -0.001668 (1/(kΩ x mA)).
SLEEP low for more than 40µs to put the device into
sleep mode for power saving. In sleep mode, the DOUT1
and DOUT2 outputs are high impedance and are pulled
high by pullup resistors. AOUT1 and AOUT2 are set to
zero-output current.
SET
0
The following equation is useful for finding the value of R
resistance given a mean of the threshold current limits:
SET
Hall Input Restart
Y = Y + m × I I < 0
(
)
0
When an input has been shut down due to a short to
ground, cycle SLEEP for 10µs to 20µs to restart the input.
If the other input is operational it is not affected. The
restart happens on the rising edge of SLEEP.
1
R=
Y
-5
Y = 6.2013 x 10 units of (1/kΩ)
0
To compute the typical input current thresholds from the
mean input current, it is necessary to obtain the hyster-
esis. The following equation finds the hysteresis given the
mean threshold current, I:
Input Current Thresholds and
Short to Ground
The input current high and low thresholds that determine
the logic level of the digital outputs are adjusted by chang-
ing the R
value. When the R
value changes, the
H = H + k x I (I < 0)
0
SET
SET
following parameters change as well: I
, I , t
IN_HYS SC BL
,
where H = -0.033463 in mA, and k = -0.08414 in mA/mA.
0
t
, t
, f
, and P .
RAMP DEL MAX
I , I , I , I , t
R
Input current threshold high = I - H/2, input current thresh-
old low = I + H/2.
, and f
MAX
are inversely pro-
increases. This
IH IL IN_HYS SC RAMP
portional to R and decrease as R
SET
SET
inverse relationship is linear. For example, a 10% change
in (1/R ) results in a 10% change in current param-
Application Information
SET
Use of Digital and Analog Outputs
eters. Conversely, time and delay parameters are linear
and directly proportional to R , and a 10% change in
The digital output can be used to provide the FP with an
interrupt signal that can represent a Hall sensor change
of status. DOUT1 and DOUT2 provide a time domain
output filter for robust noise immunity. See Figure 2.
The analog output can be connected to an ADC with an
appropriate load resistor, and can be used to perform
custom diagnostics.
SET
R
results in an 10% change in time parameters.
SET
The difference between the maximum and minimum
threshold current limits is the min/max limit spread, which
is greater than the threshold hysteresis. The min/max
spread and the hysteresis both change by the same per-
centage as the mean of the threshold current limits. The
following equation is useful for finding the mean of the
threshold current limits given a value of R
resistance:
SET
Maxim Integrated
│ 13
www.maximintegrated.com
MAX9621
Dual, 2-Wire Hall-Effect Sensor Interface
with Analog and Digital Outputs
R
MAX9621
V
CC
IN_
X
Figure 5. 3-Wire Hall-Effect Switches Configured as 2-Wire
Table 2. A Partial List of Compatible Hall Switches
PART NO.
HAL573-6
MANUFACTURER
Micronas
WEBSITE
COMMENTS
2-wire
www.micronas.com
www.micronas.com
www.micronas.com
www.allegromicro.com
HAL556/560/566
HAL579/581/584
A1140/1/2/3
Micronas
2-wire
Micronas
2-wire
Allegro
2-wire
3-wire, optimized for 2-wire
use without added resistor
A3161
Allegro
www.allegromicro.com
TLE4941/C
Infineon
www.infineon.com
2-wire
sensor ground, the ground of the MAX9621 and µP. This
ground-shift immunity eliminates the need for a ground-
connection wire, allowing a single-wire interface to the
Hall sensor.
Sleep Mode
Sleep mode can be used in applications that do not continu-
ously require the polling of the Hall sensors. In such cases,
the µP can enable the MAX9621 for a short time, check the
sensor status, and then put the MAX9621 back to sleep. A
blanking period follows upon exiting sleep mode.
Hall-Effect Sensor Selection
The MAX9621 is optimized for use with 2-wire Hall-effect
switches or with 3-wire Hall-effect switches connected as
2-wire (Figure 5). When using a 3-wire Hall sensor the
resistor R is chosen so that the current drawn by the Hall
sensor crosses the MAX9621 current threshold when
the magnetic threshold of the Hall sensor is exceeded.
A partial list of Hall switches that can be used with the
MAX9621 is given in Table 2.
Remote Ground
The MAX9621 targets applications with 2-wire Hall-effect
sensors. 2-wire sensors have connections for supply and
ground. The output level is signaled by means of modula-
tion of the current drawn by the Hall sensor from its supply.
The two threshold currents for high/low are generally in the
range of 5mA to 14mA. Thus, the interfacing of a 2-wire
sensor is not simply a matter of detecting two voltage
thresholds, but requires a coarse current-sense function.
Input Current Threshold Precision
To get the best input current threshold precision, it is rec-
Because of the high-side current-sense structure of the
MAX9621, the device is immune to shifts between the
ommended that the R
resistor be directly connected
SET
to the BAT pin. A true Kelvin type connection is best.
Maxim Integrated
│ 14
www.maximintegrated.com
MAX9621
Dual, 2-Wire Hall-Effect Sensor Interface
with Analog and Digital Outputs
Typical Application Circuit
1.8V TO 5.5V
0.1µF
BATTERY: 5.5V TO 18V
OPERATING,
R
PU
10kΩ
R
PU
10kΩ
60V WITHSTAND
R
SET
BAT
ISET
REF
REFERENCE
SLEEP
SLEEP-MODE
CONTROL
BAT
100kΩ
AOUT1
DOUT1
ADC
5kΩ
FILTER
IN1
REF
N
S
0.01µF
MICROPROCESSOR
BAT
INPUT
SHORT
DETECTION
MAX9621
REMOTE
GROUND
AOUT2
DOUT2
ADC
5kΩ
IN2
N
S
0.01µF
FILTER
REF
REMOTE
GROUND
GND
Chip Information
PROCESS: BiCMOS
Maxim Integrated
│ 15
www.maximintegrated.com
MAX9621
Dual, 2-Wire Hall-Effect Sensor Interface
with Analog and Digital Outputs
Revision History
REVISION
NUMBER
REVISION
DATE
PAGES
CHANGED
DESCRIPTION
0
1
11/09
9/11
Initial release
—
1
Added automotive qualified part
Updated Absolute Maximum Rating, added Package Thermal Resistance
Four-Layer Board in the Package Information section
2
2/20
2
For pricing, delivery, and ordering information, please visit Maxim Integrated’s online storefront at https://www.maximintegrated.com/en/storefront/storefront.html.
Maxim Integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim Integrated product. No circuit patent licenses
are implied. Maxim Integrated reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits)
shown in the Electrical Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance.
©
Maxim Integrated and the Maxim Integrated logo are trademarks of Maxim Integrated Products, Inc.
2020 Maxim Integrated Products, Inc.
│ 16
相关型号：
SI9130DB
5- and 3.3-V Step-Down Synchronous ConvertersWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY
SI9135LG-T1
SMBus Multi-Output Power-Supply ControllerWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY
SI9135LG-T1-E3
SMBus Multi-Output Power-Supply ControllerWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY
SI9135_11
SMBus Multi-Output Power-Supply ControllerWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY
SI9136_11
Multi-Output Power-Supply ControllerWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY
SI9130CG-T1-E3
Pin-Programmable Dual Controller - Portable PCsWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY
SI9130LG-T1-E3
Pin-Programmable Dual Controller - Portable PCsWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY
SI9130_11
Pin-Programmable Dual Controller - Portable PCsWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY
SI9137
Multi-Output, Sequence Selectable Power-Supply Controller for Mobile ApplicationsWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY
SI9137DB
Multi-Output, Sequence Selectable Power-Supply Controller for Mobile ApplicationsWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY
SI9137LG
Multi-Output, Sequence Selectable Power-Supply Controller for Mobile ApplicationsWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY
SI9122E
500-kHz Half-Bridge DC/DC Controller with Integrated Secondary Synchronous Rectification DriversWarning: Undefined variable $rtag in /www/wwwroot/website_ic37/www.icpdf.com/pdf/pdf/index.php on line 217
-
VISHAY
©2020 ICPDF网 联系我们和版权申明