Datasheet
TL026C
DIFFERENTIAL HIGH-FREQUENCY AMPLIFIER WITH AGC
SLFS007A – JUNE 1985 – REVISED JULY 1990
7
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
APPLICATION INFORMATION
The circuit values in Figures 6 and 7 will produce the best results in this general application. Because of
rectification and device input constraints, the circuit in Figure 6 will not provide attenuation and has about
32 dB of control range. The circuit shown in Figure 7 will have approximately 25% variation in the peak output
voltage limit due to the variation in gain of the TL592 device to device. In addition, if a lower output voltage is
desired, the output of the TL026C can be used for approximately 40 mV of controlled signal.
considerations for the use of the TL026C
To obtain the most reliable results, RF breadboarding techniques must be used. A groundplane board should
be used and power supplies should be bypassed with 0.1-µF capacitors. Input leads and output leads should
be as short as possible and separated from each other.
A peak input voltage greater than 200 mV will begin to saturate the input stages of the TL026C and, while the
circuit is in the AGC mode, the output signal may become distorted.
To observe the output signal of TL026C or TL592, low-capacitance FET probes or the output voltage divider
technique shown in Figure 6 should be used.
–
+
+
–
OUT +
OUT –
0.1 µF
0.1 µF
REF
OUT
30 kΩ
To Scope
Monitor
V
out
200 Ω
1.8 kΩ
IN –
IN +
50 Ω
AGC
10 kΩ
10 kΩ
V
AGC
A2
20 kΩ
50 Ω
V
I
+
–
10 kΩ
A1
12 kΩ
1N914
D1
0.1 µF
V1
1/2 TL082
1/2 TL082
TL026C
NOTE: V
CC+
= 6 V and V
CC–
= – 6 V for TL026C and amplifiers A1 and A2.
Figure 6. Typical Application Circuit With No Attenuation