ATS657 Datasheet, PDF (3/15 Pages) Allegro MicroSystems – The ATS657 includes an optimized Hall-effect sensing integrated circuit (IC) and rare earth pellet to create a user..

ATS657
Dynamic, Self-Calibrating, Threshold-Detecting, Differential
Speed and Direction Hall-Effect Gear Tooth Sensor IC
ELECTRICAL CHARACTERISTICS Valid over operating voltage and temperature ranges, unless otherwise noted
Characteristics
Symbol
Test Conditions
Min. Typ.¹ Max.
Unit²
Supply Voltage
Undervoltage Lockout
Reverse Supply Current
Supply Zener Clamp Voltage
Supply Zener Resistance
Supply Current
Current Level Difference
Power-On Characteristics³
V_CC
Operating, T_J < T_J(max)
V_CC(UV) V_CC = 0 → >4 V, or >4 → 0 V
I_RCC
V_CC = –18 V
V_Z(SUPPLY) I_CC = I_CC(max) + 3 mA, T_A = 25°C
R_Z
I_CC(LOW) Low-current state (Running mode)
I_CC(HIGH) High-current state (Running mode)
I_CC(SU)(LOW) Startup current level and Power-On mode
I_CC(SU)(HIGH) High-current state (Calibration)
∆I_CC
I_CC(HIGH) – I_CC(LOW)
4.0
–
18
V
–
3.5
4.0
V
–
–
–10
mA
24.0
–
–
V
–
<5
–
Ω
5.0
6.5
8.0
mA
12
14.0
16
mA
5.0
7.0
8.5
mA
12
14.5
16.5
mA
5
–
–
mA
Power-On Time
Initial Calibration
t_on
Speed < 200 Hz
–
–
2.0
ms
First Output Pulse with Direction⁴
First Output Pulse⁵
AGC Disable
Vibration Check
Time Until Correct Direction Output on
High-Speed Startup
N_DIR
N_NONDIR
N_f
N_VIBCHECK
Speed < 200 Hz, constant rotation direction
Speed < 200 Hz, constant rotation direction
Speed < 200 Hz, constant rotation direction
Speed < 200 Hz, after AGC disable
t_HIGHSU 10 kHz startup, B = 300 G_pk-pk
–
–
6
Edge
–
–
2
Edge
–
–
5
Edge
–
3
–
Edge
–
5
–
ms
Running Mode Calibration⁶
Non-Direction Pulse Output on Direction
Change
N_{NONDIR_DC}
Running mode, direction change
–
1
2
Pulse
First Direction Pulse Output on Direction
Change
N_DC
Running mode, direction change
–
2
3
Pulse
DAC Characteristics
Allowable User-Induced Differential
Offset⁷
B_DIFFEXT Both differential channels
–
±60
–
G
Output Stage
Output Slew Rate
SR_OUT
R_L = 100 Ω, C_L = 10 pF; I_CC(HIGH) → I_CC(LOW) ,
I_CC(LOW) → I_CC(HIGH) , 10% to 90% points
7
16.0
–
mA/μs
1_{Typical data is at VCC = 8 V and TA = +25°C, unless otherwise noted. Performance may vary for individual units, within the specified maximum and}
minimum limits.
2_{1 G (gauss) = 0.1 mT (millitesla).}
3_{Power-On Time is the time required to complete the initial internal automatic offset adjust; the DACs are then ready for peak acquisition.}
4_{Direction of the first output pulse on the 6}th _{edge may not be correct when undergoing vibration.}
5_{Non-direction pulse output only. See figure 3 for more details.}
6_{Direction pulse will typically occur on the 2}nd _{output pulse after a direction change. This will hold true unless an offset change at zero speed results in}
an offset correction event. Note that no output blanking occurs after a direction change.
7_{The device will compensate for magnetic and installation offsets up to ±60 G. Offsets greater than ±60 G may cause inaccuracies in the output.}
Allegro MicroSystems, Inc.
3
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com