Jumper Connections; Jumper Description - Texas Instruments TRF4900 User Manual

2.6 Jumper Connections

The default position of the jumpers on the TRF4900 EVM are configured as
shown below.
JP1
1 To R1 and C2 (Loop Filter)
To R5 and R6 (VCO Tank)
2
JP1 is a 0-Ω 0603 resistor
JP3
1
To V
CC2
To Mode Test Point
2
To Ground
3
JP3 Default is not installed
2.6.1

Jumper Description

The jumpers on the TRF4900 EVM are used for the following purposes:
-
-
-
-
JP2
1
2
3
JP2 Default is not installed
JP4
1
2
JP4 is a 0-Ω 0603 resistor
JP1
Jumper JP1 connects the VCO tank circuit to the loop filter of the PLL
circuit. The only reason to remove jumper JP1 is to test the tuning range
of the VCO tank circuit with an external power supply. The default state for
jumper JP1 is JP1-1 to JP1-2. Jumper JP1 is a 0-Ω 0603 resistor.
JP2
Jumper JP2 can be used to pull the STDBY line up to V
or pull down to ground (JP2-2 to JP2-3), if a computer connection is not
installed. The primary purpose for JP2 is as a test point to monitor the state
of the STDBY line. The default state for jumper JP2 is not connected.
JP3
Jumper JP3 can be used to pull the MODE line up to V
or pull down to ground (JP3-2 to JP3-3), if a computer connection is not
installed. The primary purpose for JP3 is as a test point to monitor the state
of the MODE line. The default state for jumper JP3 is not connected.
JP4
Jumper JP4 connects the Power-On LED to the output of the VR2 voltage
regulator. The default state for jumper JP4 is JP4-1 to JP4-2. Jumper JP4
is a 0-Ω, 0603 resistor.
Standard PC Parallel Port
To V
CC2
To STDBY Test Point
To Ground
VR1 output (VCC1)
To LED3 anode (Power on LED)
Denotes Default Connection
(JP2-1 to JP2-2)
CC
(JP3-1 to JP3-2)
CC
Evaluation Board
2-13