a4231 general features
The a4231 is a proximity sensor integrated circuit to be used with a broad range of
inductive single-coiled proximity transducers in proximity detection applications
Monolithic IC in bipolar technology
User-adjustable sensing range by means of a single external resistor
User-adjustable hysteresis (0…15%)
5.5V…35V broad supply voltage range
Low-voltage operation possible using stabilised 4.5V…5.5V voltage source
Internal voltage regulator to improve immunity against fluctuations of supply
voltage
Broad operating temperature range: -25°C...90°C
Can work with a broad selection of inductive transducers
NPN open collector output with guaranteed sink current of 150mA
Output overload/over current protection
Integrated power-on and detect LED drivers
Normally open(NO)/normally closed(NC) select pin
Broad range of operating frequencies: 100kHz…1MHz
Output over current and short-circuit protection
Easy temperature compensation of proximity transducers
Package – QFN-24
example application schematic
min. 2.2uF/40V
electrolytic
C
F
100nF/6.3V
10%
Vcc
NO/NC
220nF/6.3V
20% ceramic
VCC
C
B
P_LED
R
F
Inductive
Transducer
L
C
RES
L
1
R
F
NO/NC
L
2
220nF/6.3V
20%
Rref
GND
R
H
a4231
D_LED
OutN
GND1
C
DET
C
OVL
RSN
R
S,N
1R6 5%
125mW
OutN
91kohm
Rhyst, 5%
(optional)
Cdet, 10%
(optional)
Covl, 10%
100nF/6.3V
Typical application schematic of a proximity sensor/detector
ALPHA-MICRO [ ALPHA MICROELECTRONICS GMBH ]
