ISG3300EU
PIN FUNCTIONS
Pin No.
Pin Name
Description
Equivalent Circuit
The RFAGC pin is used to adjust gain in the
dual conversion tuner. This pin has a
positive gain vs. AGC slope. 20 dB of gain
control is available by varying the voltage
from 0.5 V to 3.3 V.
1
RFAGC
1 K
1
1 K
0.1 µF
2
3
VCC (TX)
The VCC (TX) pin powers the TX amplifier. A
5 V bias is required and nominal current is
125 mA.
The TXEN pin is used to enable/disable the
TX amplifier. When TXEN is set LOW, the
TX amplifier is disabled. In this state, a
standby current of 3 mA is required from
VCC (TX). When TXEN is set HIGH, the TX
amplifier is enabled. In this state, a
nomimal current of 125 mA is required from
VCC (TX).
TXEN
10 K
3
TXIN- is the inverting input to the TX
amplifier. The input frequency range spans
5-55 MHz.
4
5
TXIN-
4
4
5
5
TXIN+
TXIN+ is the non-inverting input to the TX
amplifier. The input frequency range spans
5-55 MHz.
The TXAGC pin is used to step control the
gain in the TX amplifier. There are 3 bits of
control.
6
TXAGC
The VCC2 (RX) pin powers the loop filter for
the first LO. A bias of 24 V - 30 V is
required and maximum current draw is
2 mA.
7
8
9
VCC2 (RX)
VCC1 (RX)
IFAGC
The VCC1 (RX) pin powers the entire RX
section. A bias of 5 V is required and
nominal current draw is
250 mA.
The IFAGC pin is used to adjust gain in the
final downconverter stage of the RX section.
The pin has a positive gain vs. AGC slope.
30 dB of gain control is available by varying
the voltage from 0.5 to 2.0 V.
1 K
9
1000 p
10
GND
Ground.
CEL [ CALIFORNIA EASTERN LABS ]
