3121, 3122, AND 3123
HALL-EFFECT SWITCHES
FOR HIGH-TEMPERATURE
OPERATION
ELECTRICAL CHARACTERISTICS over operating temperature range, at VCC = 12 V.
Limits
Characteristic
Symbol
Test Conditions
Operating
Min.
Typ.
Max.
24
Units
V
Supply Voltage
VCC
4.5
Output Saturation Voltage
Output Leakage Current
Supply Current
VOUT(SAT)
IOUT = 20 mA, B > BOP
VOUT = 24 V, B < BRP
B < BRP (Output OFF)
RL = 820 Ω, CL = 20 pF
RL = 820 Ω, CL = 20 pF
140
<1.0
4.6
400
10
mV
µA
IOFF
ICC
tr
9.0
2.0
2.0
mA
µs
Output Rise Time
Output Fall Time
0.04
0.18
tf
µs
MAGNETIC CHARACTERISTICS in gauss over operating supply voltage range.
Part Numbers*
A3121
Typ.
350
A3122
Typ.
340
A3123
Typ.
345
Characteristic
Min.
250
220
125
80
Max.
450
500
380
410
140
150
Min.
280
260
140
120
70
Max.
400
430
330
360
140
140
Min.
250
230
180
160
70
Max
440
470
300
330
140
140
BOP at TA = 25°C
over operating temp. range
BRP at TA = 25°C
over operating temp. range
Bhys at TA = 25°C
over operating temp. range
350
340
345
245
235
240
245
235
240
70
105
105
105
60
105
70
105
70
105
NOTES: Typical values are at TA = +25°C and VCC = 12 V.
OP = operate point (output turns ON); BRP = release point (output turns OFF); Bhys = hysteresis (BOP - BRP).
B
*Complete part number includes a suffix to identify operating temperature range (E- or L-) and package type ( -LT, -U, or -UA).
FUNCTIONAL BLOCK DIAGRAM
1
V
CC
REG.
3
2
OUTPUT
GROUND
X
Dwg. FH-005-2
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
Copyright © 1992, 1999, Allegro MicroSystems, Inc.