LTC2872
25
2872f
Typical applicaTions
Figure 27. Sharing RS232 Receiver Inputs
Figure 28. Low Voltage Microprocessor Interface
2872 F27
RA1 A1
A2
RXEN1
RS232
INPUT
* DOES NOT MEET RS232 SPECIFICATIONS
R
IN
RA2
RXEN2
S1
OUT1
OUT2
LTC2872
–OR–
S2
S2
1
0
1
0
S1
0
1
1
0
ACTIVE OUTPUT
OUT1
OUT2
NONE (Hi-Z)
OUT1, OUT2
R
IN
5k
5k
62.5k
2.5k*
RB1 B1
B2
RXEN1
RS232
INPUT
R
IN
RB2
RXEN2
S1
OUT1
OUT2
LTC2872
S2
2872 F28
3V TO 5.5V
1.7V TO V
CC
µP
LTC2872
LOGIC
LEVEL
SIGNALS
LINE
LEVEL
SIGNALS
RS232
AND/OR
RS485
V
CC
V
L
GND
V
CC
= 3V to 5.5V, V
L
= 1.7V to V
CC
. Logic input pins not shown are tied to a valid logic
state. External components necessary for operation are not shown.
LTC2872
26
2872f
Figure 29. RS232 RS485 Conversion
Figure 30. RS485 Repeater
Typical applicaTions
2872 F29
LTC2872
DY2RA1
RA2
Y2
A1
RS485
OUT
RS485
IN
RS232
IN
RS232
OUT
Y1
Z2
A2
B2
DY1
120Ω
2872 F29
LTC2872
DY2RA1
RA2
Y2
Z2
A2
B2
A1
B1
Y1
Z1
DY1
120Ω
120Ω
120Ω
120Ω
V
CC
= 3V to 5.5V, V
L
= 1.7V to V
CC
. Logic input pins not shown are tied to a valid logic
state. External components necessary for operation are not shown.
LTC2872
27
2872f
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa-
tion that the interconnection of its circuits as described herein will not infringe on existing patent rights.
package DescripTion
UHF Package
38-Lead Plastic QFN (5mm × 7mm)
(Reference LTC DWG # 05-08-1701 Rev C)
5.00 ± 0.10
NOTE:
1. DRAWING CONFORMS TO JEDEC PACKAGE
OUTLINE M0-220 VARIATION WHKD
2. DRAWING NOT TO SCALE
3. ALL DIMENSIONS ARE IN MILLIMETERS
PIN 1
TOP MARK
(SEE NOTE 6)
37
1
2
38
BOTTOM VIEW—EXPOSED PAD
5.50 REF
5.15 ± 0.10
7.00 ± 0.10
0.75 ± 0.05
R = 0.125
TYP
R = 0.10
TYP
0.25 ± 0.05
(UH) QFN REF C 1107
0.50 BSC
0.200 REF
0.00 – 0.05
RECOMMENDED SOLDER PAD LAYOUT
APPLY SOLDER MASK TO AREAS THAT ARE NOT SOLDERED
3.00 REF
3.15 ± 0.10
0.40 ±0.10
0.70 ± 0.05
0.50 BSC
5.5 REF
3.00 REF
3.15 ± 0.05
4.10 ± 0.05
5.50 ± 0.05
5.15 ± 0.05
6.10 ± 0.05
7.50 ± 0.05
0.25 ± 0.05
PACKAGE
OUTLINE
4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE
MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.20mm ON ANY SIDE
5. EXPOSED PAD SHALL BE SOLDER PLATED
6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION
ON THE TOP AND BOTTOM OF PACKAGE
PIN 1 NOTCH
R = 0.30 TYP OR
0.35 × 45° CHAMFER
Please refer to http://www.linear.com/designtools/packaging/ for the most recent package drawings.

LTC2872IUHF#PBF

Mfr. #:
Manufacturer:
Analog Devices Inc.
Description:
RS-232 Interface IC RS232/RS485 Dual Port Multiprotocol Transceiver with Integrated Termination (Shared I/O)
Lifecycle:
New from this manufacturer.
Delivery:
DHL FedEx Ups TNT EMS
Payment:
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