toim5232 Vishay, toim5232 Datasheet - Page 2

• Manufacturer Part Number: toim5232
• Description: Sir Endec For Irda? Applications Integrated Interface Circuit
• Manufacturer: Vishay

TOIM5232
Vishay Semiconductors
BLOCK DIAGRAM
Notes
(1)
(2)
www.vishay.com
2
PIN NUMBER SYMBOL
PIN ASSIGNMENT AND DESCRIPTION
Crystal should be connected as shown in the block diagram or in the recommended application circuit. Connect a 100 k resistor from pin 4
to pin 5 and from pin 4 and pin 5 a 22 pF capacitor to ground, respectively. When an external clock is available connect it to pin 4 leaving
pin 5 open. The external resistor of 100 k is used to accelerate the start of the oscillation after reset or power-on. The value depends on the
“Q” of the resonator. With low Q resonators no resistor is needed. The start-up time of the oscillator is between 30 µs (with piezo resonators)
and above 2 ms with high Q quartzes.
This condition is fulfilled with all Vishay IR transceivers.
10
12
13
14
16
17
18
19
6, 8, 11, 15, 20
1
2
3
4
5
7
9
RD_LED
TD_LED
RD_232
TD_232
RESET
V
TD_IR
RD_IR
BR/D
GND
CC_SD
V
X1
X2
S1
S2
CC
[e-mail], [e-mail],
Transmit LED indicator driver. Use 180  current limiting resistor in series to LED to connect
Receive LED indicator driver. Use 180  current limiting resistor in series to LED to connect
User programmable bit. Can be used to turn on/off a front-end infrared transceiver (e.g., an
User programmable bit. Can be used to turn on/off a front-end infrared transceiver (e.g., an
Resets all internal registers. Initially must be high (“1”) to reset internal registers. When high,
The V
RESET pin can be controlled by either the RTS or DTR line through RS232 level converter.
RS232 TXD data line is connected (via a level shifter) to TD_232 input pin. The TXD - signal
is appropriately shortened and applied to the output TD_IR, driving the TXD input of the IR
transceiver. The RXD line of the transceiver is connected to the RD_IR input. This signal is
stretched to the correct bit length according to the programmed bit rate and is routed to the
Crystal input clock, 3.6864 MHz nominal for 9.6 kbit/s default setting. Input for external
the TOIM5232 sets the IrDA default bit rate of 9600 bit/s, sets pulse width to 1.627 µs.
transceiver when applying the reset signal to the TOIM5232. When using devices with
For technical questions within your region, please contact one of the following:
external SD like TFDU4203, the reset line can be used directly as shutdown signal.
Data received from the RS232 port is interpreted as control word. The control word
Received signal data output of stretched signal to the RS232 RXD line (using level
CC_SD
programs the baud rate width will be effective as soon as BR/D return to low.
Data input from the infrared transceiver, min. pulse duration 1.63 µs
Ground in common with the RS232 port and IrDA transceiver ground
This pin can be used to shut down a transceiver (e.g., TFDx4xxx).
output is simply an inverted reset signal which allows shutdown of a TFDx4x00
Input of the signal to be transmitted from the RS232 port TXD line
clock
Data output of shortened signal to the infrared transceiver.
SIR Endec for IrDA
(1)
TD_232
RD_232
RESET
Integrated Interface Circuit
. Option: 7.3728 MHz for 19.2 kbit/s default operation.
BR/D
BR/D = 0, data communication mode:
Minimum hold time for resetting is 1 µs.
Output polarity: Inverted RESET input.
infrared module at the adapter back).
infrared module at the adapter front).
RS232 RXD line at the RD_232 pin.
Disables the oscillator when active.
GND
BR/D = 1, programming mode:
(passing the level converter).
Baud rate control/data
to V
to V
X1
Baud
generator
Logic
Endec
Supply voltage
Oscillator
DISCRIPTION
CC
CC
V
converter).
CC
Crystal
(V
(V
NC
CC
CC
X2
®
= 3.3 V).
= 3.3 V).
(1)
Applications
TD_IR
RD_IR
TD_LED
S2
V
RD_LED
S1
CC_SD
[e-mail]
18079
(2)
Document Number: 81749
Rev. 1.2, 17-Nov-10
I/O
O
O
O
O
O
O
O
I
I
I
I
I
ACTIVE
High
High
High
High
Low
Low
Low
Low
Low
Low