7) Enable the output powers of the RF signal generators.

8) Using the calibration results from step 4, set the

generator outputs to produce -30dBm into RFINA

and RFINB.

9) Verify that an output voltage at VOUTA and VOUTB

of approximately 1.3V is measured on the volt-

meters.

10) Verify that an output voltage at VOUTD of approxi-

mately 1V is measured on the voltmeter.

11) Adjust the signal-generator power levels up and

down to see a corresponding change in VOUTA,

VOUTB, and VOUTD.

Detailed Description

The MAX2016 EV kit is a fully assembled and tested

surface-mount PCB that evaluates the MAX2016 dual

logarithmic detector/controller. The RF inputs utilize

50Ω SMA connectors for convenient connections to test

equipment.

Individual Log Amps (VOUTA and VOUTB)

The MAX2016 uses two individual log amps to measure

the input power applied to RFINA and RFINB. These

amplifiers are normally configured in detector mode to

provide an output signal proportional to the applied

input power level. The individual log amp output can

also be operated in a controller mode, if desired, to

control an external device using the input power as the

control parameter.

Detector Mode

The MAX2016 EV kit is assembled with a 0Ω resistor for

R1 and R2. This sets the slope of the individual log amp

output signal to approximately 18mV/dB (RF =

100MHz). To increase the slope of either individual out-

put signals, VOUTA or VOUTB, increase the value of R1

or R2, respectively. For example, if a 40kΩ resistor is

used for R1, the slope for the VOUTA signal increases

to 36mV/dB.

Power-Controller Mode

For operation of either VOUTA or VOUTB in controller

mode, remove R1 or R2. A set-point voltage must then

be applied to the SETA or SETB inputs. Use a DAC, an

external precision voltage supply, or the internal refer-

ence output and resistor-divider string to apply the set-

point voltage to SETA or SETB. Operate SETA or SETB

at voltages between 0.6V and 1.6V. RFINA or RFINB

are connected to the RF source and the VOUTA or

VOUTB is connected to the gain-control pin of the sys-

tem under control.

In the power-controller mode (Figure 2), the DC voltage

at OUTA or OUTB controls the gain of the PA leading to

a constant output power level. (Note: Only one con-

MAX2016 is a dual controller/detector, the second

channel can be easily implemented by using the adja-

cent set of input and output connections).

Difference Amplifier (VOUTD)

Comparator

The MAX2016 integrates two comparators to monitor

the difference in power levels (gain) of the RFINA and

RFINB. By default, R4 and R5 are set to be 0Ω.

thus disabling the comparator operations. To enable

the comparator operations, R4 and R5 must be

removed. Load C16 and C17 with 0.1µF capacitors.

Use the reference voltage from the MAX2016 to gener-

ate two voltages through a resistor-divider network

(R7/R8 and R9/R10) to set the CSETH and CSETL trip

points. Alternately, R4, R5, and R7–R10 can be

removed and external voltages applied at CSETH and

CSETL to set the comparator trip points. Be sure to

observe the voltage limits specified in the MAX2016

data sheet.

The logic outputs at each comparator monitor the gain

independently. The COR output, (A + B), ORs the out-

puts of both comparators to tell whether the gain of the

amplifier falls in the range. For more information, refer to

the Applications Information section in the MAX2016

data sheet.

MAX2016 Evaluation Kit

_______________________________________________________________________________________

3

MAX2016

LOGARITHMIC

DETECTOR

TRANSMITTER

SET-POINT

DAC

20kΩ

20kΩ

OUTA/

OUTB

SETA/

SETB

RFINA/

RFINB

POWER

AMPLIFIER

COUPLER

GAIN-CONTROL

INPUT

Figure 2. Power-Controller Mode