Integral IL1815D Amplifier ic for sensors with different conductance Datasheet

IL1815
AMPLIFIER IC FOR SENSORS WITH DIFFERENT CONDUCTANCE
Functional Description
Designed IC is an integrated circuit (IC) of the
amplifier for sensors with different conductance.
IL1815 – is an IC of adaptive amplifier
increasing analog signal from the sensor and
transmitting a strobe of pulses from IC output
into electrical circuit of motor engine control
device. The amplifier ensures one short output
pulse leading edge of which coincides with
negative half-wave, crossing zero of input
analog signal produced by alternating magnetic
field of inductive sensor coil.
TA = –40 ÷ +125°С
Functions
IC is purposed for application in automotive electronics in injection controller block as
well as in engine control system for:
• crankshaft position (condition) control;
• Switching when crossing zero;
• engine rotation speed control;
• tachometer (rotation speed measurement);
•
engine check (testing).
IC IL1815 is analog to microcircuit of the third integration scale and comprises 131 elements.
The circuit is implemented in 14-pin DIP-package of MS-001AA (IL1815N) type and in 14-pin SOpackage of MS-012AB (IL1815D) type.
Connection of loading of 1 kOhm to IC output (to pin 10) is tolerable.
Features
•
•
•
•
•
•
•
•
Adaptive hysteresis
One-polar power supply mode
Influence of «ground» on input
Precise choice of the initial ignition moment
Operation in the supply voltage range of 2,5 V up to 12 V
control of input (pin 3) by signal coming into external resistor with amplitude from 75 mV up to
120V.
• Compatibility with CMOS - logic
1
IL1815
Pin symbols.
NC
01
14
SYN2
GND
02
13
NC
IN
03
Plastic
12
CN3
NC
04
DIP or SO -
11
C1
CN1
05
package
10
GO
NC
06
09
SYN1
CN2
07
08
VP
Pin description table.
Table of pin description in IC IL1815N (for 14-pin DIP package of MS-001AA type) and IC
IL1815D (for 14-pin SO package of MS-012AB type)
Number
01
02
03
04
05
Symbol
NC
GND
IN
NC
CN1
Description
Not connected
Common output
Signal input
Not connected
Input of sensitivity threshold control
06
07
08
09
10
11
12
13
14
NC
CN2
Vp
SYN1
GO
CI
CN3
NC
SYN2
Not connected
Output of capacitance peak detector
Supply output from voltage source
Synchronization input
Gate output
Choice input
Reference voltage output
Not connected
Output of RC – synchronization
2
IL1815
Table of maximum ratings
Symbol
VP
Ptot
Tstg
Тс
II
Parameter
Supply voltage
Maximum dissipated power 1)
Storage temperature
Maximum chip temperature2)
Input current
min
max
Unit
2,0
-65
-
12,0
1250,0
150
125
±30
V
mW
°С
°C
mA
min
max
Unit
Note:
Short-term temperature rise of chip up to 150°С is tolerable.
Maximum absolute ratings
Symbol
Parameter
VP
Supply voltage
2,5
12,0
V
Тс
Maximum chip temperature
125
°C
Table of electrical parameters (for Та(ambient)=25°С; supply voltage Vp=10 V and in compliance with
connection circuit given in Fig. 1 without L1)
Symbol
Parameter
Test conditions
Target
Unit
min
max
IP
Consumption current
fI=500 Hz, output 09=2 V,
6,0
mA
output 11=0,8 V
W
Width of reference pulse on
fI=from 1 Hz to 2 kHz,
70,0
130,0
mks
output 12
R1=150 kOhm, C1=0,001
mkF
IIB
Bias current of logic input
VI=2 V
5,0
mkA
(on outputs 09 and 11)
1)
ZI
Input impedance
VI=5 В (rms)
12,0
28,0
kOhm
VCROSS
Threshold of crossing zero
VI =100 mV
25,0
mV
(on output 03)
VTL
Threshold of logic input
On outputs 09 and 11
0,8
2,0
V
VOH
High output voltage
R4=1 kOhm (output 10)
7,5
V
VOL
Low output voltage
ISINK=0,1 mA (output 10)
0,4
V
VTA
Input switching threshold
Mode 1: output 05 is
30,0
60,0
mV
open,
VI ≤135 mV
2)
Mode 1: output 05 is
% from
40,0
90,0
open,
U03 + PK
VI ≥230 mV
Mode 2: output 05 is
200,0
450,0
mV
shorted to VP
Mode 3: output 05 is
-25,0
25,0
mV
shorted to «ground»
ILS
Output leakage current on
V12=11 V
10
mkA
output 12
VSV
Saturation voltage on
I12=2 mA
0,4
V
output 12
Note:
1) Measured with external input resistor of 18 kOhm. The circuit comprises series connected resistor of 1
kOhm with diode, connected to «ground» which attenuate input signal;
2) numerical value of the rate on the controlled variable VTA, is defined by percentage of U03 signal sum
incoming on output 03 and PK voltage level on output 07 of peak detector.
3
IL1815
Electrical parameters ( for Та(ambient)=25°С; supply voltage Vp=10 V and in accordance with
connection circuit shown in figure 1 without L1)
Symbol
Parameter
Test conditions
IIS
Bias current of signal input
(on output 03)
VI=0 V direct component
(output 03)
Signal input
pin 03
± pulses
X
X
± pulses
Target
Typical
value
200,0
Table 1 – Truth table
Choice input
Synchronization
output 11
input
pin 09
L
X
H
H
H
L
L
L
RCsynchronization
pin 14
RC
X
X
L
Unit
nA
Gate output
pin 10
Pulses = RC
H
L
Crossing zero level
External loading connection circuit and preferred application circuit
Vp
t = 0,673RC
R1
150
kOhm
С1
0,001
mkF
14
R2
5,6
kOhm
13
12
R4
1
kOhm
11
10
09
08
Microcircuit
Decelerating
controller of
data
transfer
+
_
_
_
+
+
01
02
03
R3
18
KOhm
VI
04
L1
05
06
С2
0,33
mkF
07
R5
1,6
MOhm
Functionality description
Under normal operation (function) conditions the signal synchronized by reference
voltage source (from pin 12) having passed the controller of data transmission delay (see
fig.1) and transformed by external electrical circuit returns into the IC. Then, logic input (pin
11) enables to choose whether synchronization signal (from clock synchronization input –
4
IL1815
pin 09) or processed input signal (from pin 03), having passed the controller of data
transmission delay, for transmission to output stage of IC logic block.
The amplifier is started by incoming positive threshold voltage that is generated during
effect of voltage peak on output 07. This peak appears when input signal comes into
output 03 of the circuit and its maximum value varies in time with input signal amplitude.
Thus, input hysteresis changes with amplitude of input signal. That allows electrical circuit
to perceive the signal where high-frequency noise is grater than amplitude of input signal
of lower frequency. Minimum amplitude of input signal VI = 75 mV.
Latching circuit of input voltage.
Voltage of input signal on output 03 is internally fixed.
Напряжение входного сигнала на выводе 03 внутренне зафиксировано. Remaining
limit of input signal on this output is ensured by external resistor R3 (see fig.1), which is to
be chosen to provide maximum current (amplitude value) ±3 mA in normal operation
conditions.
Vp
T1
T4
T2
R1
1kOhm
T5
T3
R2
2kOhm
T7
R3
1kOhm
T6
Output 03
Input voltage latching circuit.
Positive inputs of amplifiers (from output 03) are fixed in electrical circuit (see fig.2) by
connected in series resistor R3 and diode T4 connected to «ground». Therefore for
changes of input signal exceeding 500 mV relative to «ground» level, input current will be
«dropped» on «ground» through output 02 of the device. On the other hand, active limits
of the above mentioned latch tie output 3 usually to 350 mV below «ground» level for
negative input signals (see R1, R2, T2, T3 in fig.2). Thus, for transmitting input signal more
5
IL1815
than 350 mV below «ground» level, current of input output 03 (right up to 3 mA) will be
sourced from supply output VP. If output VP is not shunted insufficiently from incoming
pulsation voltage, normal operation of the device on output VP will be disturbed. Similarly,
minor changes of «ground» potential appear on output 02 of the device, in consequence of
which, poor quality of equipment earth related to «ground» of input signal may cause
unreliable device operation. Thus, to ensure combined input voltage and frequency range
of IC operation it’s necessary to think over an adequate device ground connection and
avoid pulsations of supply voltage VP.
Limitation of input current.
As mentioned above, current limit for signal input (output 03) is ensured by the user by means
of external resistor R3 (fig.1). For applications where signal of input voltage is not symmetric
regarding «ground» the worst case of voltage peak may be calculated by the following formula:
R3MIN = (VIN peak) / 3 mA
(1)
In applied example shown in figure 1 ( when R3=18 KOhm ), recommended maximum input
signal voltage is ±54 V (amplitude value).
Operation of sensor actuation (detection device) when crossing zero.
LM1815 is purposed for operation as sensor of crossing zero starting unit internal counting
when input signal negative half-wave (trailing edge) crosses zero. As against other sensors of
crossing zero, LM1815 can’t be started until input signal crosses switching threshold on positive
part of waveform, only afterwards electrical circuit is connected again. The following crossings of
zero are disregarded unless switching threshold is exceeded again. This switching threshold
changes depending on connection of output 05. There can be three different operation modes.
Mode 1, output 05 is not connected (open).
In this mode when amplitude of input signal more than typical value ±75 mV and less than ±
135mV - typical value of switching threshold makes 45 mV. Under these conditions input signal
has to cross first 45 mV of switching threshold in positive direction in order to «equip» the sensor
of crossing zero, and then cross zero in negative direction to start it.
If signal amplitude is less than 30 mV (minimum in the range of electrical characteristics), short
pulse does not guarantee IC starting (switching).
Input signals with amplitude more than ±230 mV ensure switching threshold of 80% (typical
value) of input voltage peak. Capacitor of peak detector in the device on output 07 stores
(memorizes) the value regarding positive input peaks determining switching threshold. Input
signals have to exceed this switching threshold in positive direction in order to «equip» sensor of
crossing zero which operates on negative wavefront (edge) of input signal.
Pulses of peak detector change quickly according to increase in amplitude of input signal and
attenuate owing to the property of externally connected to output 07 resistor, decreasing input
signal. In case when amplitude of input signal decreases quicker than voltage stored on the
capacitor of peak detector, output signal may decrease until the voltage on capacitor becomes
very minor, equal to the «ground» level.
Note that after input voltage is fixed, waveform observed on output 03 is not identical to the one
observed on variable reactive sensor. Just as voltage stored on output 07 is not identical to pulse
(variable) voltage appears on output 03.
Mode 2, output 05 is connected to VP.
Under this mode minimum amplitude of input signal is ±200 mV. IC is started on negative wave
(edge) of input signal crossing zero, after switching threshold on positive wave (edge) of input
signal is exceeded.
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IL1815
Mode 3, output 05 - grounded.
With grounded output 05, input switching threshold is set from 0 V (typical rate) up to ±25 mV
(maximum). Positive wave (front) of input signal crossing zero «equip» the zero detector and the
next coming negative wave (edge) - start the IC. This is the main IC application mode.
Single-ended operation synchronization.
Pulse synchronization is preset by resistor and capacitor connected to output 14. Preferred
maximum resistor value - 150 kOhm. Capacitance may be changed if needed (according to
application requirements), until capacitor variable is not showing any leakage which will result
adversely in RC - constant variable.
Width of input pulse is determined by formula:
W = 0.673 x R x C
(2)
Since normally generated is a string of pulses of a determined width, preferred maximum input
signal frequency is:
FI (maximum) = 1 / (1.346 x R x C) (3)
In an applied example shown in figure 1 (R=150 kOhm, C=0.001 mkF), preferred maximum
input frequency will usually be 5 kHz. Under influence of input frequency higher than preferred FI
(maximum) value, operation of electrical circuit may be unreliable. For the applications which do
not require generation of pulses into electrical circuit (i.e. in static operation mode), output 14 may
be directly connected to the «ground».
Logic inputs and outputs.
In some systems it’s necessary to generate pulses, for example, under conditions of engine
shutdown (when motor car is stopped), when variable reactive sensor has no output signal.
External input pulses from output 09 strobed (pulses controlled) from choice input (output 11), go
to output 10 when there is a high level («H») on output 11. Output 12 - a direct output of data
(generated pulses), is not subject to influence of logic on output 11.
Input/output pins 09, 11, 10 and 12 are compatible with CMOS logic. Besides, pins 09, 11 and
12 are compatible with TTL logic. Output 10 is not meant for controlling TTL loading (see fig.3).
Output 12 - an open collector of NPN-transistor.
Pins 01, 04, 06 and 13 do not have internal connections and may be «grounded».
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IL1815
Diagram of IC output.
Vp
R1
40Ohm
T1
T4
Output 10
T3
T2
R2
2,7kOhm
8
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