AD834JRZ-RL Analog Devices Inc, AD834JRZ-RL Datasheet - Page 10

• Manufacturer Part Number: AD834JRZ-RL
• Description: IC,Analog Multiplier,BIPOLAR,SOP,8PIN,PLASTIC
• Manufacturer: Analog Devices Inc

Specifications of AD834JRZ-RL

• Function: Analog Multiplier
• Number Of Bits/stages: 4-Quadrant
• Package / Case: 8-SOIC (3.9mm Width)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

AD834
EXPLANATION OF TYPICAL PERFORMANCE
CHARACTERISTICS AND TEST CIRCUITS
Figure 4 is a plot of the mean-square output vs. frequency for
the test circuit of Figure 8. Note that the rising response is due
to package resonances.
For frequencies above 1 MHz, ac feedthrough is dominated by
static nonlinearities in the transfer function and the finite offset
voltages. The offset voltages cause a small fraction of the funda-
mental to appear at the output, and can be nulled out (see
Figure 5).
THD data represented in Figure 6 is dominated by the second
harmonic, and is generated with 0 dBm input on the ac input
and 1 V on the dc input. For a given amplitude on the ac input,
THD is relatively insensitive to changes in the dc input ampli-
tude. Varying the ac input amplitude while maintaining a
constant dc input amplitude affects THD performance.
Rev. E | Page 10 of 20
The squarer configuration shown in Figure 8 is used to determine
wideband performance because it eliminates the need for (and
the response uncertainties of) a wideband measurement device
at the output. The wideband output of a squarer configuration is
a fluctuating current at twice the input frequency with a mean
value proportional to the square of the input amplitude.
By placing the capacitors, C3/C5 and C4/C6, across the load
resistors, R1 and R2, a simple low-pass filter is formed, and the
mean-square value is extracted. The mean-square response can
be measured using a DVM connected across R1 and R2.
Care should be taken when laying out the board. When using
the DIP package, mount the IC socket on a ground plane with a
clear area in the rectangle formed by the pins. This is important
because significant transformer action can arise if the pins pass
through individual holes in the board; improperly constructed test
jigs have caused oscillation at 1.3 GHz.