MAX9921AUB+T Maxim Integrated Products, MAX9921AUB+T Datasheet - Page 11

• Manufacturer Part Number: MAX9921AUB+T
• Description: IC SENSOR HALL EFFECT 10-MSOP
• Manufacturer: Maxim Integrated Products
• Type: Hall Effect Sensorr

Specifications of MAX9921AUB+T

• Input Type: Voltage
• Output Type: Logic
• Interface: 2-Wire
• Current - Supply: 1.3mA
• Mounting Type: Surface Mount
• Package / Case: 10-MSOP, Micro10™, 10-uMAX, 10-uSOP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Table 2. Diagnostic Truth Table (Diagnostic Mode)
If the V
IN1 and IN2 shut off current to both Hall sensors and
ERR, OUT1, and OUT2 go low. When V
the proper range, both IN1 and IN2 restart, following a
blanking cycle.
If either IN1 or IN2 is open (I
ing input shuts off current to the Hall sensor. If IN1 or
IN2 is loaded, it exits the open input fault condition and
restarts the corresponding Hall input, following a blank-
ing cycle.
Figure 3. Several MAX9921s Connected to a Common Reverse-Polarity Diode
INPUT
DIAG
Hall Sensor Protection from Supply Transients
1
1
1
1
1
1
1
1
BAT
R
ISET
voltage is lower than 6V or exceeds 18V,
BAT
ISET
IN1
IN2
GND
Dual, 2-Wire Hall-Effect Sensor Interface
MAX9921
______________________________________________________________________________________
ERR
0
0
0
0
1
1
1
1
REVERSE-POLARITY DIODE
OUT1
OUT2
DIAG
ERR
Hall Inputs Open Condition
OE
IN
OUTPUT
FOR MAX9921s
< 2mA), the correspond-
OUT1
0
0
1
1
0
0
1
1
BATTERY
BAT
OUT2
0
1
0
1
0
1
0
1
returns to
No fault
IN1 open circuit, or IN1 open circuit and fault on IN2
IN1 shorted to battery, or IN1 shorted to battery and fault on IN2
IN1 shorted to ground, or IN1 shorted to ground and fault on IN2
V
fault masks all other faults)
IN2 open circuit
IN2 shorted to battery
IN2 shorted to ground
R
BAT
ISET
out of range, or power-up or restart and blanking cycle (dominant
BAT
ISET
IN1
IN2
GND
If either IN1 or IN2 is shorted to the battery (V
+ 100mV), the MAX9921 shuts off current to the corre-
sponding Hall sensor. In this case, if IN1 or IN2 is more
than 1V above V
BAT. In such a condition, the current level in the Hall
input should not exceed 100mA. Therefore, all the
MAX9921s together can share a separate reverse-
polarity protection diode to avoid powering up other cir-
cuitry sharing a common diode (Figure 3).
MAX9921
OUT1
OUT2
DIAG
ERR
OE
with Diagnostics
BAT
DIAGNOSIS
, it may back-drive current into
Hall Input Shorted to Battery
CIRCUITRY
OTHER
GND
BAT
REVERSE-POLARITY DIODE
FOR OTHER CIRCUITRY
IN
> V
BAT
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