GL3276A
GL3276A
Description
Pin Configuration
The GL3276A is a bipolar analog ICs specifically
developed for use in infrared remote control system
receiving preamplifiers. Capable of accepting a
photodiode directly, these ICs house a high gain
initial amplifier, a limiter, a band-pass filter, a
detection circuit and a waveform shaping circuit
assembled on a single chip
(SOP)
VCC1
1
8
IN+
Out
2
7
IN-
Features
GL3276A
• Less changes of malfunction associated with a
high-frequency lighting fluorescent lamp internal
trap circuit.
VCC2
3
6
CD
FO
4
5
GND
• The central frequency can be varied with an
external resistance: FO=30 to 80KHz
FO rimming reduce central frequency variance.
• Few external parts.
- Internal pull-up resistance.
- Internal power filter resistance.
- Lower-capacitance external capacitor
• Open collector output
Open collector output with a pull-up resistance.
Block Diagram
FO
VCC2
VCC1
4
3
1
RS
Initial
Stage
Amplifier
IN+
Limiter
Detector
BPF
+
TRAP
8
Waveform
Sharper
ABLC
7
IN-
RL
5
6
GND
1
CD
Output
2
GL3276A
Absolute Maximum Ratings ( TA = 25oC )
SYMBOL
PARAMETER
VALUE
UNIT
VCC
Supply Voltage
6.0
V
IOUT
Output Current
2.5
mA
PD
Allowable Power Dissipation
270
mW
TOPR
Operating Temperature
- 20 to 75
o
- 40 to 125
o
TSTG
Storage Temperature
C
C
Recommended Operating Condition
SYMBOL
PARAMETER
MIN
TYP
MAX
UNIT
VCC
Supply voltage
4.5
5.0
5.5
V
fIN
Input frequency
30
38
80
KHz
Electrical Characteristics ( VCC = 5.0V, TA = 25oC )
SYMBOL
PARAMETER
TYP
MAX
UNIT
ICC
Supply current
1.2
2.8
mA
VIN
Input voltage
IIN = 0A
IIN = -330uA
2.0
0.6
2.5
0.8
3.1
1.7
V
AV
Voltage gain
fIN = 38KHz
VIN = 30uVP-P
70
76
80
dB
FBW
BPF bandwidth
-3dB Bandwidth
VIN = 30uVP-P
2.0
2.5
3.0
KHz
rIN
Input impedance
fIN = 38KHz CW
VIN = 0.2uVP-P
80
110
160
KΩ
fIN = 38KHz
burstwave
VIN = 500uVP-P
440
770
uS
fIN = 38KHz
burstwave
VIN = 50mVP-P
440
tPW1
Output pulse
width
tPW2
VOL
Low Level
Output voltage
VOH
Low Level
Output voltage
Note 1: rIN =
47
KΩ
TEST CONDITION
MIN
REMARK
Note 1
Note 2
0.2
4.8
5.0
770
uS
0.4
V
V
(where VIN = input level, VX = test value)
(VIN / VX)－1
Note 2:
input burst
wave form
38KHz Carrier
600us
600us
output pulse
2
GL3276A
Pin Description
SYMBOL
NO.
PIN FUNCTION
VCC1
1
Power input
VCC2
3
Power output
GND
5
Ground
• Apply a voltage of 5V± 10% to pin 1.
As the power is output to pin 3 through the internal
power filter resistance, connect an electrolytic capacitor
to pin 3.
IN +
8
Input
• With an internal impedance of 110KΩ (typ.) pin 8 can
accept a PIN photodiode directly.
An automatic bias level control (ABLC) circuit prevents
the input from being saturated by external light, assuring
bias level stability for the input pin.
IN -
7
Initial amplifier
Gain setup
• Initial amplifier differential inverted output.
Its gain can be set up with an external impedance.
FO
4
BPF
Frequency
setup
• The central frequency of the band-pass filter can be
varied with an external resistance. A built-in trap
circuit prevents malfunctions associated with a highfrequency lighting fluorescent lamp.
CD
6
Detection
capacitor
• Pin to which a detection capacitor is connected.
Output
• Open collector output with pull-up resistance.
Its capability to drive a CMOS or TTL makes for easy
connection with a receiving microcomputer.
The GL3276A ha an active low output.
OUT
2
Sample Application Circuits
C1
C1: 1500pF
C2: 0.01uF
C3: 47uF
C2
Photo diode
R1
8
7
6
5
IN+
IN-
CD
GND
GL3276A
VCC1
Out
VCC2
FO
1
2
3
4
Power Supply
R2
C3
Output
3
R1: 0 ~ 1KΩ
R2
(KΩ)
50
100
120
130
140
150
160
170
FO
(KHz)
80.5
47.3
40.6
38.0
35.6
33.6
31.8
30.0
GL3276A
Typical Characteristics ( TA = 25oC )
Frequency vs Resistance (R2)
90
2.5
80
2.0
FO (KHz)
ICC Supply Current (mA)
Supply Current vs Supply Voltage
1.5
1.0
70
60
50
40
0.5
30
3.0
3.5
4.0
4.5
5.0
5.5
6.0
40
60
80 100 120 140 160 180 200
VCC Supply Voltage (V)
R2 (KΩ)
Voltage Gain vs Input Frequency
Gain vs Capacitance (C1)
90
70
VCC = 5V
R2 = 150KΩ
VI = 30uVP-P
78
AV Voltage Gain (dB)
AV Voltage Gain (dB)
80
60
50
40
30
VCC = 5V
R2 = 130KΩ
VI = 80uVP-P
20
74
70
66
10
25
30
35
40
45
50
1000
FIN Input Frequency (KHz)
2000
3000
C1 (pF)
4
4000
5000