U2532B
Preliminary Information
TELEFUNKEN Semiconductors
Rev . A1, 27-Sep-96 1 (10)
IR Transmitter and Receiver
Description
The IC U2532B is a complete IR-Transmitter-Receiver
IC according to the new IrDA 1.0 standard.
ASK-modulation is also possible. Only an external
PIN-photodiode and an infrared emitting diode with
current limiting resistor must be connected to the
corresponding pins. The amplifier with Schmitt-Trigger
formed output signal and the IR-driver need no further
external components. The IC allows data rates from
2.4 kbit/s to 115.2 kbit/s and up to 500 kHz for
ASK-modulation. Two different sensitivity modes, which
can be programmed by applying a “High” or “Low”
voltage at pin SC, ensure either an increase in
transmission distance or a bit error rate of 1E-9. An
internal AGC allows proper operation under EMI
conditions.
Features
D
Data rates up to 115.2 kbit/s
D
Wide supply voltage range (3 to 5.5 V)
D
AGC for EMI immunity
D
AGC reset
D
High and low sensitivity mode
D
BER < 1E-9 in the low sensitivity mode
D
Power-On reset
Applications
D
IR data transmission
D
Compatible to IrDA
D
Bidirectional IR data transmission
D
Ability to receive ASK modulation
Case: SO16
Driver
Amp
(AGC) ST
VCC
RL
RxD
TxD
95 10210
SC Reset
Figure 1.
U2532B
TELEFUNKEN Semiconductors
Rev . A1, 27-Sep-96
Preliminary Information
2 (10)
Pin Description
16
15
14
13
1
2
3
4U2532B 12
11
10
5
6
7
9
8
95 10244
P_GND
TxD
RxD
Reset
VCC
SC
NC
NC
NC
IRED
O_GND
NC
NC
A_GND
NC
IN
Figure 2. Pinning
Pin Symbol Function
1 P_GND Power ground
2 TxD T ransmitter input
3 RxD Receiver output
4 Reset AGC-Reset
5 VCC Supply voltage
6 SC Sensitivity Control
7, 8,
10, 12,
13, 16
NC Not connected
9 IN Photodiode input
11 A_GND Analog ground
14 O_GND Output ground
15 IRED IR-Emitter
Block Diagram
BIAS
TIA AGC
CGA
+
–
COMP
DRV
611
15
1
3
14
2
9
4
5
95 10211
Figure 3. Block diagram
U2532B
Preliminary Information
TELEFUNKEN Semiconductors
Rev . A1, 27-Sep-96 3 (10)
Functionality of the Various Circuit Blocks
Transimpedance Amplifier (TIA)
The input stage provides the necessary bias voltage for the
photodiode and ensures decoupling of the useful signal.
This involves processing the dc and ac portions in sepa-
rate parts of the circuit, BIAS (Bias voltage) and TIA. The
BIAS circuit separates the dc part (sunlight, incandescent
light) from the input signal. The ac portion of the input
current is fed to an inverting amplifier with a sufficiently
low input impedance (TIA). The TIA prevents the signal
slopes to be negatively affected by the junction capaci-
tance of the photodiode.
Controlled Gain Amplifier (CGA)
The CGA consists of two differential amplifiers. The total
gain is 17 in the high sense mode (Sensitivity Control In-
put “High”) and can be reduced to 8 if the Sensitivity
Control Input is set to “Low”. In the low sense mode a
BER of 1E-9 is guaranteed. In the high sense mode
eventually generated output pulses must be suppressed by
software handling. The lower and upper cut-off frequen-
cies of the amplifier are 25 kHz and 900 kHz
respectively. Additionally the overall gain can be
attenuated by 30 dB in 2 dB steps. The attenuation is digi-
tally controlled by the AGC (Automatic Gain Control)
circuit.
Comparator (COMP)
The comparator compares the output signal of the CGA
to an internal threshold voltage. The output of that
comparator is directly connected to an collector output
stage. An internal pull up resistor of 20 k
W
is provided.
Automatic Gain Control (AGC)
The AGC adjusts the sensitivity of the receiver according
to the strength of the incoming signals. When the input
signal increases, the amplification of the CGA is reduced
to a value where a BER < 1E-9 is still guaranteed, but sig-
nals from disturbers can be effectively suppressed. With
this feature a proper data transmission can be maintained
also in the presence of energy saving lamps and ceiling
lamps that are common in offices. The dynamic range of
the AGC is max. 30 dB. This provides the ability to sup-
press also strong disturbers. As the AGC acts when the
input signal increases, the transmission distance is re-
duced if disturbances have to be suppressed. The AGC is
digitally controlled and therefore not dependent on any
time constant. The amplification of the CGA is set at ev-
ery input pulse or input burst for ASK-modulation and is
maintained until the next input signal is detected. The sig-
nal strength determines whether to reduce, increase or
maintain the gain. If no input signal is detected in 18 ms,
the AGC considers the data transmission to be finished
and increases the gain by a 2 dB step. W ithin every 18 ms
the gain is increased by an additional 2 dB step, until the
maximum gain of the CGA is reached. If a “High” signal
is applied at the reset (Pin 4), the AGC is set to maximum
sensitivity. Incoming signals don‘t influence the AGC.
Under this biasing condition it is possible to get maximum
transmission distance also in the presence of a known
strong disturber, if of course the signals of the disturber
can be succesfully suppressed by software handling in the
microprocessor. During “Power-On” the AGC is set to
maximum sensitivity. The gain of the AGC is maintained
while the transceiver is transmitting.
Transmitter
IRED Driver (DRV)
The IRED driver DRV is also monolithically integrated
on the transceiver chip providing a high impedance input
to drive a fast IR emitter diode. The “active high” input
signal drives the output stage. This stage mainly consists
of an input amplifier and an open collector NPN transistor
that is saturation controlled. The output transistor is capa-
ble of driving a lood current up to 1 A.
U2532B
TELEFUNKEN Semiconductors
Rev . A1, 27-Sep-96
Preliminary Information
4 (10)
Absolute Maximum Ratings
All voltages are referred to A_GND (Pin 11).
Parameters Test Conditions / Pins Symbol Min. Typ. Max. Unit
Supply voltage Pin 5 VCC –0.5 6 V
T ransmitter input voltage Pin 2 VIN(TxD) –0.5 VCC+0.5 V
Sensitivity control voltage Pin 6 VSC –0.5 VCC+0.5 V
Reset voltage Pin 4 V(Reset) –0.5 VCC+0.5 V
Receiver output voltage Pin 3 VO(RxD) –0.5 VCC+0.5 V
LED driver Pin 15 V(TxD) –0.5 6 V
Input currents Pins 2, 4, 6 and 15 1 mA
Receiver sinking current Pin 3 IL(RxD) 10 mA
Photodiode input Pin 9 VIN –0.5 VCC V
Power dissipation Ptot 75 mW
Junction temperature Tj150 °C
Ambient temperature range Tamb –40 125 °C
Storage temperature range Tstg –40 150 °C
Soldering temperature 230 °C
Average driver current Pin 15 Id(DC) 100 mA
Repeated pulsed driver c. < 90
m
s, ton < 20%, Pin 15 Id(RP) 500 mA
Peak driver current < 2
m
s, ton < 10%, Pin 15 Id(PK) 1 A
Thermal Resistance
Parameters Symbol Value Unit
Junction ambient RthJA 180 K/W
U2532B
Preliminary Information
TELEFUNKEN Semiconductors
Rev . A1, 27-Sep-96 5 (10)
Electrical Characteristics
Test conditions: VCC = 5 V, Tamb = 25°C, unless otherwise specified
Parameters Test Conditions / Pins Symbol Min. Typ. Max. Unit
Receiver
Supported data rates 2.4 115.2 kbit/s
Supply voltage range Pin 5 VCC 3 5 5.5 V
Supply current Pin 5 IS 1.3 2.5 mA
Sensitivity control voltage
“Low” Low sense mode Pin 6 VSC 0.2 0.5 V
Sensitivity control voltage
“High” High sense mode Pin 6 VSC 2.0 VCC V
Input threshold
current SC > 0.5 V
VCC = 3 V Pin 9 ilNmin 60 90 nA
Input threshold
current SC > 2.4 V, VCC = 3 V
Pin 9 ilNmin 30 45 nA
Input threshold current
for ASK modulation SC < 0.5 V or open
VCC = 3 V Pin 9 ilNmin
(ASK) 200 400 nA
Input threshold current
for ASK modulation SC < 2.4 V or open
VCC = 5 V Pin 9 ilNmin
(ASK) 120 250 nA
Max. signal pulse input
current Sensitivity independent
Pin 9 ilNmax 6 mA
DC input current VIN > 0 V Pin 9 IIN 200
m
A
Output voltage RxD Non active Pin 3 VOH VCC–0.5 V
Output voltage RxD Active; IL = 4 mA Pin 3 VOL 0.2 0.5 V
Rise time C = 15 pF,R = 2.2 k
Pin 3 tr0.5
s
Fall time C = 15 pF,R = 2.2 k
Pin 3 tf0.3
s
Output pulse width 2.4 kbit/s,
78
s pulse width Pin 3 tp7 15
s
Output pulse width 115.2 kbit/s,
1.6
s pulse width Pin 3 tp2.5 4
s
Output delay time 115.2 kbit/s,
1.6
s pulse width
– Output level 0.5
VCC
– Leading edges of signals
– Related to optical input
Pin 3
td1 2
s
Jitter 115.2 kbit/s,
1.6
s pulse width
– Period of 10 bits, all
“ones”
– Leading edges of signals
Pin 3
tj2
s
AGC dynamic range Pin 3 30 dB
AGC single step Pin 3 2 dB
Max. reset time 15 steps, covering full dy-
namic range of AGCPin 3
treset 270 400 ms
U2532B
TELEFUNKEN Semiconductors
Rev . A1, 27-Sep-96
Preliminary Information
6 (10)
UnitMax.Typ.Min.SymbolTest Conditions / PinsParameters
Transmitter
Output voltage IRED
“Low” Id = 300mA with appropri-
ate current limiting resistor
Pin 15
VOL(TxD)0.3 0.5 V
Logic “Low” transmitter
input voltage Pin 2 VIN (TxD) 0.4 0.8 V
Logic “High” transmitter
input voltage Pin 2 VIN (TxD) 2 VCC V
Output leakage current VO(TxD) = 6 V Pin 15 Id0 10
m
A
Output rise time Id = 300 mA Pin 15 tr300 ns
Output fall time Id = 300 mA Pin 15 tf300 ns
Output pulse width 115.2 kbit/s
1.6
m
s pulse width Pin 15
tp1.4 1.6 2.7
m
s
Overshoot over final
current Pin 15
d
Id 25 %
Jitter 115.2 kbit/s,
1.6
m
s pulse width
–Period of 10 bits, all
“ones”
– Leading edges of signals
Pin 15
tj0.2
m
s
U2532B
Preliminary Information
TELEFUNKEN Semiconductors
Rev . A1, 27-Sep-96 7 (10)
Typical Performance Characteristics
Test condition: Vcc = 5 V
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
–40 –20 0 20 40 60 80 100 120 140
Rel Supply Current
Tj Temperature ( °C )12471
Figure 4. Supply current vs. temperature
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
–40 –20 0 20 40 60 80 100 120 140
Rel Input Threshold Current
Tj Temperature ( °C )12472
Figure 5. Input threshold current vs. temperature (receiver)
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
–40 –20 0 20 40 60 80 100 120 140
Rel Output Low Voltage
Tj Temperature ( °C )12473
Figure 6. Output voltage IRED “LOW” vs. temperature
(transmitter)
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
–40 –20 0 20 40 60 80 100 120 140
Rel Pulse Width
Tj Temperature ( °C )12474
Figure 7. Output pulse width vs. temperature
(receiver, 115 kbit/s)
U2532B
TELEFUNKEN Semiconductors
Rev . A1, 27-Sep-96
Preliminary Information
8 (10)
Application Circuit
The diagram below shows the typical application for the
IC U2532B. The detector diode and IR emitter can also
be obtained from TEMIC. As emitter a high speed in-
frared emitting diode like TSHF5400 is recommended.
For improving output power two diodes can be connected
in series. An external current limiting resistor is used to
adjust the appropriate forward current. The resulting cur-
rent of the emitter, with the settings RL = 5
W
and
VCC
= 5 V, is Id = 300 mA and the corresponding typical
radiant intensity of a single diode is IE = 120 mW/sr.
The IR radiation detector BPV22NF is a high speed and
high sensitive PIN photodiode in a plastic package with
a spherical side view lens. Because of a large radiant sen-
sitive area of A = 7.5 mm2 a typical output current of
Ira = 85
m
A with Ee = 1 mW/cm2 and
l
= 870 nm is
achieved. A transmitting distance of approximately 3.5 m
is possible. Rs and C are the low pass filter network to sup-
press power supply noise and other disturbances. At
pin RxD the output signal can be received. Optionally an
external load resistor can be connected from pin 3 to V CC,
if a smaller pull up resistor than 20 k
W
is desired.
16
15
14
13
1
2
3
4U2532B
12
11
10
5
6
7
9
8
TxD
RxD
Reset
SC
m
C
100
W
RS
RL
5
W
C
470 nF
VCC
(5 V)
TSHF
5400
BPV22NF
95 10212
Figure 8.
U2532B
Preliminary Information
TELEFUNKEN Semiconductors
Rev . A1, 27-Sep-96 9 (10)
Dimensions in mm
94 8875
Figure 9.
U2532B
TELEFUNKEN Semiconductors
Rev . A1, 27-Sep-96
Preliminary Information
10 (10)
Ozone Depleting Substances Policy Statement
It is the policy of TEMIC TELEFUNKEN microelectronic GmbH to
1. Meet all present and future national and international statutory requirements.
2. Regularly and continuously improve the performance of our products, processes, distribution and operating systems
with respect to their impact on the health and safety of our employees and the public, as well as their impact on
the environment.
It is particular concern to control or eliminate releases of those substances into the atmosphere which are known as
ozone depleting substances (ODSs).
The Montreal Protocol (1987 ) and its London Amendments (1990) intend to severely restrict the use of ODSs and
forbid their use within the next ten years. Various national and international initiatives are pressing for an earlier ban
on these substances.
TEMIC TELEFUNKEN microelectronic GmbH semiconductor division has been able to use its policy of
continuous improvements to eliminate the use of ODSs listed in the following documents.
1. Annex A, B and list of transitional substances of the Montreal Protocol and the London Amendments respectively
2. Class I and II ozone depleting substances in the Clean Air Act Amendments of 1990 by the Environmental
Protection Agency (EPA) in the USA
3. Council Decision 88/540/EEC and 91/690/EEC Annex A, B and C (transitional substances) respectively.
TEMIC can certify that our semiconductors are not manufactured with ozone depleting substances and do not contain
such substances.
We reserve the right to make changes to improve technical design and may do so without further notice.
Parameters can vary in different applications. All operating parameters must be validated for each customer
application by the customer. Should the buyer use TEMIC products for any unintended or unauthorized
application, the buyer shall indemnify TEMIC against all claims, costs, damages, and expenses, arising out of,
directly or indirectly, any claim of personal damage, injury or death associated with such unintended or
unauthorized use.
TEMIC TELEFUNKEN microelectronic GmbH, P.O.B. 3535, D-74025 Heilbronn, Germany
Telephone: 49 (0)7131 67 2831, Fax number: 49 (0)7131 67 2423
