AIC1863
IR Preamplifier for Remote Control System
Analog Integrations Corporation
4F, 9, Industry E. 9th Rd, Science Based Industrial Park, Hsinchu Taiwan, ROC
www.analog.com.tw
DS-1863-00
TEL: 886-3-5772500 FAX: 886-3-5772510
1
n
FEATURES
l
Only Two External Components Required Other
than the Photodiode.
l
Easy to Integrate into Module due to Small Chip
Size.
l
Minimized Chances of Malfunction Due to Am-
bient Light.
l
Low Power Consumption.
l
Center Frequency of Band Pass Filter Adjusta-
ble by an External Resistor.
l
Microcomputer Compatible.
n
APPLICATIONS
l
IR Remote Control Receivers for Consumer
Electronic Products, such as TVs, VCRs,
VCD/DVD Players, Audio Devices, Air Condi-
tioners, Electric Fans...etc.
n
DESCRIPTION
The AIC1863 is a high performance infrared re-
mote control preamplifier. Especially, it has ex-
cellent interference suppression capability. The
infrared pulses arriving at the photodiode are
treated by the trans-impedance amplifier and
amplified by the auto-gain control amplifier, limit-
ter amplifier, and band-pass filter. The following
evaluation circuits, including the comparator, in-
tegrator, and schmitt-trigger, demodulate the
transmitted digital signal. Reduction of sensitivity
due to external interference is achieved by the
short-time boost and long-time control circuits,
which prevent interference voltages from affecting
the output.
n
TYPICAL APPLICATION CIRCUIT
Photo
Diode
C1
0.1
F
Vcc (+5V)
V
OUT
110K(fo =38KHz)
R1
IN
AIC1863
AGND
FO
DGND
OUT
NC
CA
8
7
6
5
4
3
2
1
VCC
IR Remote Control Receiver
n
ORDERING INFORMATION
AIC1863
2
AIC1863 XX
PACKAGE TYPE
S: SMALL OUTLINE
D: DICE
TEMPERATURE RANGE
C: 0
C~+70
C
ORDER NUMBER
AIC186 3CS
(PLASTIC SO)
AIC186 3CD
(DICE)
PIN CONFIGURATION
TOP VIEW
AGND
1
3
4
2
8
6
5
7
VCC
NC
OUT
DGND
FO
IN
CA
n
ABSOLUTE MAXIMUM RATINGS
Supply Voltage ..................................................... ... ... ... ... .......................................
5.5V
Input Voltage .......................................................... ... ... ... ... ................................. 5 Vp-p
Operating Temperature Range
........................................ ... ... ... ..................... -20
C~80
C
Storage Temperature Range .................................... ... ... ... ... .................... - 65
C~ 150
C
n
TEST CIRCUIT
+
0.1
F
C1
Vcc(+5V)
V
OUT
110K
R1
IN
AIC1863
AGND
FO
DGND
OUT
NC
CA
8
7
6
5
4
3
2
1
VCC
+
+
C3
0.47
F
S5
S4 S3
S2
R2
I
IN
100
A
C2
0.47
F
47K
V
IN
S1
n
ELECTRICAL CHARACTERISTICS
(VCC= 5V, Ta=25
C, unless otherwise
specified.)
PARAMETER
TEST CONDITIONS
SYMBOL
MIN.
TYP.
MAX.
UNIT
Supply Voltage
Vcc
4.5
5.0
5.5
V
Input Pin Voltage (1)
I
IN
=0
A
V
IN1
3.8
4.2
4.4
V
Input Pin Voltage (2)
I
IN
=100
A
V
IN2
1.5
2.1
2.7
V
Low Level Output Voltage
V
OL
0.1
0.3
V
AIC1863
3
High Level Output Voltage
V
OH
4.70
4.94
V
Voltage Gain
100
V
P-P
, 38KHz
A
V
76
81
dB
BPF Characteristics
100
V
P-P
, 28KHz, 35KHz,
41KHz, 48KHz (note 1)
A
Q
4
9
dB
Input Impedance
0.5V
P-P
, 38KHz (note 2)
R
IN
4
11
K
Detecting Ability (1)
100
V
P-P
, 38KHz
600
S ON Time,
0.2 Duty Cycle
T
D1
360
520
680
S
AIC1863
4
n
ELECTRICAL CHARACTERISTICS
(Continued)
PARAMETER
TEST CONDITIONS
SYMBOL
MIN.
TYP.
MAX.
UNIT
Detecting Ability (2)
50mV
P-P
, 38KHz
600
S ON Time,
0.2 Duty Cycle
T
D2
540
670
800
S
Switch On Delay Time
100
V
P-P
, 38KHz
600
S ON Time,
0.2 Duty Cycle
T
ON
100
250
400
S
Switch Off Delay Time
100
V
P-P
, 38KHz
600
S ON Time,
0.2 Duty Cycle
T
OFF
150
220
400
S
LCC Slew Rate
C1=0.1
F
dv/dt
0.8
V/S
Quiescent Current
I
CC
0.4
0.7
1.0
mA
NOTE 1: Ratio of the AC level at 35KHz and the AC level at 28KHz denotes A
Q1
.
A
Q1
=
20
l
og
measured value (f = 35KHz)
measured value (f = 28KHz)
Ratio of the AC level at 41KHz and the AC level at 48KHz denotes A
Q2
.
A
Q2
=
20
l
o g
measured value (f = 41KHz)
measured value (f = 48KHz)
NOTE 2: Input level denotes V
I
and measured level denotes V
X
, then
R
IN
=
47K
V / V - 1
I
X
n
BLOCK DIAGRAM
6
AGND
3
4
DGND
1
CA
7
8
5
VCC
L.C.C.
S.B.C.
T.I.A.
A.G.C.
IN
AUTOMATIC
BIAS LEVEL
CONTROL
V
B
+
-
OUT
WAVEFORM
SHAPER
FO
DETECTOR
COMPARATOR
B.P.F.
LIMITTER
AMP.
INTE-
GRATOR
AIC1863
5
n
PIN DESCRIPTIONS
PIN 1: CA
- LCC capacitor connection pin.
PIN 2: NC
- No Connection.
PIN 3: OUT
- Output pin.
PIN 4: DGND - Digital ground.
PIN 5: IN
- Input pin (photodiode connection pin).
PIN 6: AGND - Analog ground.
PIN 7: FO
- Band pass filter center frequency set-
ting pin.
PIN 8: VCC
- Power supply pin.
n
TYPICAL PERFORMANCE CHARACTERISTICS
Quiescent Current (mA)
Quiescent Current vs. Supply Voltage
Supply Voltage (V)
4.5
5
5.5
0.5
0.55
0.6
0.65
0.7
0.75
0.8
4.6
4.7
4.8
4.9
5.1
5.4
5.2
5.3
Ta=25
C
Supply Current (mA)
0.50
0.55
0.60
0.65
0.70
0.75
Supply Current vs. Temperature
Temperature (
C)
-20
0
20
40
60
80
Vcc= 5V
40
50
60
70
80
Voltage Gain vs. Input Signal Frequency
Voltage Gain (dB)
10
100
Ta=25
C
V
CC
=5V
Input Signal Frequency (KHz)
20
30
40
50
20
30
40
50
60
70
Center Frequency (
KHz)
60
70
80
90
100
110
120
130
140
150
160
Center Frequency vs. Externally Attached
Resistance to Pin 7
Externally Attached Resistance to Pin 7 (K
)
Ta=25
C
V
CC
=5V
AIC1863
6
n
TYPICAL PERFORMANCE CHARACTERISTICS
(Continued)
0
1
2
3
4
Pin 5 DC Voltage (V)
0
20
40
60
80
100
120
140
160
180
200
Pin 5 DC Voltage vs. Input DC Current
Input DC Current (
A)
Ta=25
C
V
CC
=5V
n
APPLICATION INFORMATIONS
l
THE OPERATION
AUTOMATIC BIAS LEVEL CONTROL
An ABLC (Automatic Bias Level Control) circuit is
built into the input section to prevent the input level
from being saturated by the external disturbing
lights, such that this circuit is actuated by a strong
external disturbing light to fix the bias level of the
input terminal.
TRANS-IMPEDANCE AMPLIFIER (T.I.A.)
The Trans-impedance amplifier is an inverted ampli-
fier with a sufficiently low input resistance, which
amplifies the input photocurrent pulses. The resis-
tance of the input at the signal frequency should
not be too high. Otherwise the wanted signal would
be lost to the junction capacitance of photodiode.
AUTO-GAIN CONTROL AMPLIFIER (A.G.C.)
The voltage gain of auto-gain control amplifier is
controlled by the voltage at CA pin. In so doing, it
supports the long-time interference suppression of
the evaluation circuit.
EVALUATION CIRCUIT
The signal delivered from the band-pass filter is
compared with a reference by the detector com-
parator. This reference is determined by the short-
time boost circuit and the long-time control circuit.
The inherent offset of the detector comparator and
the reference determine the sensitivity of the
evaluation circuit. The integrator is controlled by the
above mentioned comparison. Its output is used to
control the output stage after being processed
through a schmitt-trigger. Use of the integrator
keeps the output free of short-time interference.
The ground of the evaluation circuit is routed out
separately at pin 4, in order to minimize effect of
the output switching edges.
SHORT-TIME BOOST CIRCUIT (S.B.C.)
The short-time boost circuit reduces the sensitivity
of the evaluation circuit after reception of a signal.
This prevents short-time interference from affecting
the output. The reduction in sensitivity is achieved
by boosting the reference input of the detector
comparator.
LONG-TIME CONTROL CIRCUIT (L.C.C.)
The long-time control circuit improves the circuit's
resistance to long-time interference by adapting the
sensitivity of the evaluation circuit and the amplifi-
cation of the AGC amplifier. Reduction of the
evaluation circuit sensitivity is thereby achieved in
the same way, as for the SBC, by raising the refer-
ence input of the detector comparator. The external
capacitor C1 is charged as long as the signal is
delivered from band pass filter and the voltage of C1
provides the necessary control voltage for AGC
amplifier.
AIC1863
7
l
DESIGN GUIDE
SETTING THE CENTER FREQUENCY OF BAND
PASS FILTER
Connect a resistor from pin 7 to VCC to set the
center frequency of band pass filter. The center fre-
quency will be lower if the resistor value is higher.
The relationships between center frequency of band
pass filter and the resistance of external resistor
are tabulated as below:
f
0
(KHz)
33
36
37
38
40
56.8
R1(K
)
130
118
114
110
104
72
SETTING LCC CAPACITOR C1
With the transmitted data signal with duty cycle
lower than 0.4 (average, during the whole transmis-
sion), the detection sensitivity is unchanged all the
time. Otherwise, with the transmitted data signal
with duty cycle higher than 0.4, the detection sen-
sitivity will maintain unchanged for a proportional
time period and gradually be reduced due to in-
creasing control voltage at CA pin. Higher duty cy-
cle enables more reduction of detection sensitivity
in specific transmission time. Increasing the ca-
pacitance of C1 causes longer transmission time
as duty cycle higher than the maximum allowable
duty cycle.
GROUNDING
The AGND pin, DGND pin and all the external parts
are recommended to be connected as much as
possible to "one ground point" for good noise per-
formance.
n
PHYSICAL DIMENSIONS
l
8 LEAD PLASTIC SO (unit: mm)
SYMBOL
MIN
MAX
A
1.35
1.75
A1
0.10
0.25
B
0.33
0.51
C
0.19
0.25
D
4.80
5.00
E
3.80
4.00
e
1.27(TYP)
H
5.80
6.20
L
0.40
1.27
D
H
e
A
B
A1
C
E
L
AIC1863
8
n
DIE DIMENSION
PIN6
PIN 5
PIN 3
PIN4
PIN 1
PIN 8
PIN 7
OUT
1209, 104
DGND
1477, 64.5
IN
1447, 357.5
AGND
1477, 776.5
FO
137.5, 726.5
VCC
149.5, 373.5
CA
540, 107.5
0, 0
UNIT:
m
DIE SIZE:
1535
845
m
2
PAD SIZE:
100
100
m
2
DIE THICKNESS: 15
1.5 mil
PDF 
ZIP