RFSA3623 Datasheet, PDF (12/16 Pages) RF Micro Devices – 5MHz to 6000MHz, Digital Step Attenuator

RFSA3623
Evaluation Board Jumper Programming
Jumpers
S1
S2
S3
S4
Connector
P3
Signal
Logic
Voltage
AO
A1
A2
Position
0
1
0
1
0
1
0
1
Note: Default jumper settings are BOLD.
U1 Connection
VDD (From P1)
VIO (From P4)
GND
U1_VDD
GND
U1_VDD
GND
U1_VDD
Comment
External Address
External Address
External Address
Evaluation Board Programming Using USB Interface
Serial Addressable Mode
All programming jumpers on the evaluation board are set to the default values indicated in the table. Refer to the
Control Bit Generator (CBG) Software Reference Manual for detailed instructions on how to setup the software for use.
Apply the supply voltage to P1. Select ‘RFSA3623’ from the RFMD Parts List of the CBG user interface. Set the
attenuation value using the CBG user interface. The attenuator is set to the desired state and measurements can be
taken. Note that the external address bits must all be set to ‘0’ when using the USB interface as the CBG software
does not have the capability to set the external address in the serial data stream at this time.
Evaluation Board Programming Using External Bus
Serial Addressable Mode
This configuration allows the user to control the attenuator through the P4 connector using an external harness.
Remove the USB interface board if it is currently installed on the evaluation board. Connect a user-supplied harness to
the P4 connector. Note that the top row of P4 contains the serial bus signals and the bottom row is ground.
Programming jumper S1 is set to ‘0’. External address jumpers S2 through S4 can be set to any value desired by the
user. Apply the supply voltage to P1. Send the appropriate signals onto the serial bus lines in accordance with the
Serial Addressable Mode Timing Diagram. The attenuator is set to the desired state and measurements can be taken.
Default Power-up State
This default attenuation state is maximum (15.75dB) when supply voltage is applied to the attenuator. The LE signal
must be held to logic ‘0’ during power-up.
RF Micro Devices Inc. 7628 Thorndike Road, Greensboro, NC 27409-9421
DS150128
For sales or technical support, contact RFMD at +1.336.678.5570 or [e-mail].
The information in this publication is believed to be accurate. However, no responsibility is assumed by RF Micro Devices, Inc. ("RFMD") for its use, nor for any infringement of patents or other rights of
third parties resulting from its use. No license is granted by implication or otherwise under any patent or patent rights of RFMD. RFMD reserves the right to change component circuitry, recommended
application circuitry and specifications at any time without prior notice.
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