UPC2798GR Datasheet, PDF (10/15 Pages) NEC – IF DOWN CONVERTOR IC FOR DIGITAL CATV

UPC2798GR
PIN FUNCTIONS
Pin
Pin
No. Name
1 AGC IN1
Pin Voltage
Typ. (V)
1.5
2 AGC IN2
1.5
3
VAGC
0~5
Function and Explanation
RF input pins. Pins 1 and 2 are each base inputs
to a differential amplifier. In the case of a single-ended
input, bypass the unused pin to ground through a
capacitor.
Gain control pin of the mixer input amplifier. VAGC up
= gain up. It is recommended to use a 100k Ω voltage
divider at this pin.
Equivalent Circuit
4
AGC
Control
1
3
Reg
2
4
AGC
Control
4
VCC1
5.0
5 OSC OUT
4.0
6
GND
0.0
7 OSC B2
2.4
8 OSC C1
4.6
9 OSC C2
4.6
10 OSC B1
2.4
Supply voltage pin for the downconverter block. This
pin should be connected with a bypass capacitor
(e.g., 1000 pF) to minimize ground impedance.
Output pin for the internal oscillator. This pin may be
connected to the input of a PLL synthesizer.
4
5
REG
Ground pin. This pin must be connected to system
ground. Form ground pattern as wide as possible to
minimize ground impedance.
Input pins for the internal oscillator. The internal
oscillator consists of a balanced amplifier.
7 8 4 9 10
Reg
Reg