LTC CONFIDENTIAL
1
June 17, 2003
DC656A DEMO BOARD QUICK START GUIDE
INTRODUCTION
The DC656A demo board is used to evaluate the LTC5532ES6, RF power detector with integrated
output buffer and voltage reference. The LTC5532 has provisions for offset and gain adjustments. The
LTC5532ES6 converts an RF input signal at pin 6 (RF) to a DC voltage at pin 2 (Vout). The RF input
frequency range is 300 MHz to 7000 MHz. Maximum input power is 8 dBm. The output voltage at
Vout will start at an initial DC value of typically 120 mV +/- 10 mV. When the RF signal is applied, the
output voltage will increase.
The optional R1 termination resistor and C3 output shunt capacitor are not placed on PCB. R2 and R3
are 10 kohm resistors. This reflects the gain setting = 2. E3 is an offset adjustment pin. It should be
connected to ground for initial tests and measurements.
The DC656A demo board is easily set up for evaluating the LTC5532ES6 RF power detector
performance. Follow the procedures outlined below and connections on the attached diagram for proper
operation.
1.
Connect the input DC power supply (2.7V to 6V) to E1. Connect the power supply ground to.
Connect J1 to the RF signal generator via coaxial cable with an SMA connector. It is common
practice to include a 2dB or 3dB pad to minimize reflections back into the signal generator.
2. Connect E3 (offset adjustment pin) to ground.
3. Apply an RF input signal and measure the Vout DC voltage at E2.
Optional measurements can be done by changing the R2 resistor from 10 kohm to higher value to
increase the gain of the part, if desired.
Additionally the offset voltage can be set to any voltage above 120 mV and the output (Vout) will track.
