Pin Number
Function
FX118DW
FX118P
Xtal: Output of clock oscillator inverter.
1
2
3
No Internal Connection: It is recommended that, to improve noise conditions, this pin is connected to VSS.
LPF(1) Out: The output of the Channel 1 Lowpass Filter. It is to be coupled to “B Mod(1) In” via a 1.0µF
capacitor – see Figure 2.
B Mod(1) In: The input to Channel 1 balanced modulator. Internally biased at VDD/2 it is to be coupled to
“LPF(1)” via a 1.0µF capacitor – see Figure 2.
4
5
VSS: Negative supply (GND).
6
7
C1 Out: The analogue output of Channel 1.
C1 Amp Output: Channel 1 amplifier with external components (see Figure 2) can be used to provide gain in
the signal path.
8
9
C1 In: The negative input of Channel 1 Amplifier. Recommended external components are shown in Figure 2.
C2 In: The negative input of Channel 2 Amplifier. Recommended external components are shown in Figure 2.
C2 Amp Output: Channel 2 amplifier with external components (see Figure 2) can be used to provide gain in
10
the signal path.
11
12
C2 Out: The analogue output of Channel 2.
VBIAS: The internal analogue bias line at VDD/2. It should be decoupled to VSS via a 1.0µF or greater capacitor.
See Figure 2.
13
14
15
16
B Mod(2) In: The input to Channel 2 balanced modulator. Internally biased at VDD/2 it is to be coupled to
“LPF(2)” via a 1.0µF capacitor – see Figure 2.
LPF(2) Out: The output of the Channel 2 Lowpass Filter. It is to be coupled to “B Mod(2) In” via a 1.0µF
capacitor – see Figure 2.
VDD: The positive supply rail. A single positive supply voltage (3.0v – 5.0v) is required. Levels and voltages
within the Duplex Frequency Inverter are dependent upon this supply.
Xtal/Clock: 4.433619 MHz Xtal or externally derived clock is injected at this pin. See Figure 2. Operation of
the FX118 without a Xtal or clock input may cause device damage.
2
CMLMICRO [ CML MICROCIRCUITS ]
