MCP2140A-I/SO Microchip Technology, MCP2140A-I/SO Datasheet - Page 22

• Manufacturer Part Number: MCP2140A-I/SO
• Description: IC IRDA CONTROLLR DTE/DCE 18SOIC
• Manufacturer: Microchip Technology

Specifications of MCP2140A-I/SO

• Package / Case: 18-SOIC (7.5mm Width)
• Controller Type: IRDA Standard Protocol Stack Controller
• Interface: UART
• Voltage - Supply: 3 V ~ 5.5 V
• Current - Supply: 2.2mA
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Product: Controller Area Network (CAN)
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT
• Ic Function: Standard Protocol Stack Controller
• Brief Features: Includes UART-to-IrDA Standard Encoder/decoder Functionality, Infrared Supported
• Supply Voltage Range: 2V To 5.5V
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: MCP2140DM-TMPSNS - BOARD DEMO FOR MCP2140
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

MCP2140A
2.13
The MCP2140A requires an infrared transceiver for the
optical interface. This transceiver can be a single-chip
solution (integrated) or be implemented with discrete
devices.
The MCP2140A was designed to interface to a
integrated Optical Transceiver, although it can interface
to a discrete solution as long as the MCP2140A
specifications are meet.
The MCP2140 required a wave shaping circuit to inter-
face to typical integrated optical transceivers. An
Example circuit is shown in the user guides of the
MCP2140 Demo and evaluation boards. This circuit is
shown in
transceivers RXD signal.
The MCP2140A requires that the RXD signal is not
inverted.
example wave shaping circuit can be modified with
simple component replacement to support the
MCP2140A.
characteristics before and after the modified wave
shaping circuit
Table 2-2
example MCP2140 wave shaping circuit, and the
component changes required to make the PCB layout
compatible with the MCP2140A. The layout is not
required to be changed since the BAT54 is a Schottky
Diode in a SOT-23-3 package with the desired pin
connections, the capacitor footprint can easily be
replaced by a resistor (0Ω), and the R16 resistor can be
removed since it is not involved with the circuit.
Figure 2-18
that can be done.
TABLE 2-2:
DS22050A-page 22
C19
R11
R13
R16
R20
Q1
(SOT-23-3)
Symbol
Note 1: This device is changed from MCP2140
Optical Interface
Figure
Figure 2-17
shows the schematic symbols for the
shows a simple “Blue Wire” modification
Wave Shaping Circuit implementation.
Figure 2-19
Capacitor (47pF)
—
—
Resistor
(100Ω)
Resistor
(4.7 kΩ)
PNP Transistor
(MMUN2111LT1)
(Figure
MCP2140 Device
2-16. This circuit inverts the optical
EXAMPLE MCP2140 WAVE
SHAPING CIRCUIT TO
MCP2140A COMPONENT
CHANGES
(value)
Component
2-17).
shows how the Microchip
shows the RXD signal
Resistor (0 Ω)
—
—
—
Resistor
(4.7 KΩ)
Schottky Diode
(BAT54)
Device (value)
MCP2140A
(1)
(1)
(1)
Table 2-4
integrated optical transceivers.
FIGURE 2-16:
FIGURE 2-17:
RXD
RXD
47 pF
0Ω
C19
C19
shows a list of common manufacturers of
+5V
+5V
optional
optional
optional
optional
R11
R11
R14
10 kΩ
R15
10 kΩ
R14
10 kΩ
R15
10 kΩ
R13
R13
MCP2140 WAVE SHAPING
CIRCUIT FOR
INTEGRATED OPTICAL
TRANSCEIVER
MCP2140A
MODIFICATIONS OF
MCP2140 WAVE SHAPING
CIRCUIT
© 2007 Microchip Technology Inc.
1
Schottky
Diode
4.7 kΩ
+5V
+5V
2
R20
(MCP2140 Pin 1)
(MCP2140A Pin 1)
RXPDREF
RXPDREF
3
Q1
R16
100Ω
R16 (Open)
4.7 kΩ
MMUN2111LT1
Q1
BAT54
R20
(MCP2140
Pin 18)
(MCP2140A
RXPD
Pin 18)
RXPD