User's Guide

PRO-FLEX TRANSCEIVER MODULES
USER’S GUIDE
The information in this document is subject to change without notice.
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PFLX-UG-0002-00-17 Copyright © 2009 LS Research, LLC Page 24 of 29
Reference Value Tol.
Voltage/
Power
Manufacturer Part Number Description
R1 R2 R3 R4
R7 R9 R14
R15 R18
R19 R20
R21 R23
R24 R30
R31 R32
R33 R34
R35 R38
R54 R58
NP THICK FILM 0402 SMT RESISTOR
R64 R65
R66 R67
R68 R69
NP 5% 125mW Any 0805 SURFACE MOUNT RESISTOR
U1 2.5V 1% MICROCHIP MCP1525T-I/TT 2.5V VOLTAGE REFERENCE
U3 2.5V ±4°C MICROCHIP MCP9700T-E/TT LOW POWER LINEAR ACTIVE THERMISTOR
U7 SENSIRION SHT11 HUMIDITY AND TEMP SENSOR
Table 3 No-Pop Components
6.2 Revision History
6.2.1 Rev. A Schematic Changes
Initial production release.
6.2.2 Rev. B Schematic Changes
Change Description
Change Description Continuation and/or Change
Justification
Swap UART TX and RX pins on the Development Board
Right now TX on the silicon labs part is wired to TX on the
Module and same for Rx. Tx of the Module s/b going to
Rx of the SI Labs part and Rx of the Module to RX of the
SI Labs part
Table 4 Rev. B Schematic Changes
6.2.3 Rev. C Schematic Changes
Change Description
Change Description Continuation and/or Change
Justification
Rearranged reference designators for LEDs as follows:
Was LED4, now LED1
Was LED6, Now LED4
Was LED1, now LED6
More intuitive and easier to read arrangement
Disconnect J20 pin 3 from J1 pin 2. New supply scheme doesn’t use switch isolation
Connect J1 pin 2 to GND net New supply scheme doesn’t use switch isolation
Connect J20 pin 3 to GND net New supply scheme doesn’t use switch isolation
Insert D2 in series between J20 pin 1 (anode) and J1 pin
1/C18 node (cathode)
So the module doesn't burn