AFS2 RADIOMETRIX [Radiometrix Ltd], AFS2 Datasheet - Page 2

• Manufacturer Part Number: AFS2
• Description: 500mW UHF RF power amplifier
• Manufacturer: RADIOMETRIX [Radiometrix Ltd]

User interface
Figure 3: AFS2 pin-out and dimension
Pin description
NOTES:
Radiometrix Ltd.,
Pin
RF
1
2
3
User
1
2
3
RF Module
1
2
3
1. This amplifier expects a 100mW power level to be output from the radio on transmit.
2. The TXE line should be tied to the TR2M TXE input. When this line is asserted (low) the amplifier is
3. If a low power transmit mode is needed, the receive path is bidirectional, and capable of carrying up
4. Following the return of TXE to inactive (high), the AFS2 remains in transmit mode for another 15mS,
5. This unit requires a regulated +5v rail, during transmit, and during receive.
6. This version cannot be used with in i1200 modem mode, unless a separate means of driving the
7. This is a 500mW output product. Good grounding (mount onto a groundplane and tack solder all can
turned on (drawing 280-300mA) and the RF switching connects it between the module and the
aerial. When it is inactive (high or floating) a low loss path is provided for the rx signals, from aerial
to the module.
to 100mW of power. In this case the radio must be set to transmit, but the AFS2 pin TXE must be left
in the inactive (high) state.
to allow the output of the radio to ramp down, before changing over to receive mode.
TXE pin is provided. (see relevant application notes)
walls to this), good quality aerials, properly mounted, and a low impedence power supply are
required if full performance is to be reliably obtained. If feasible, we recommend mounting the
module, and the board it is on, inside a metal enclosure, with the RF cable taken to a bulkhead
connector. All signal and power feeds should be filtered and/or decoupled.
Failure to observe these measures can cause modulation distortion ('recirculation' effects) or
instability. Also be aware of the effect that the strong RF fields generated by this device (and it's
aerial) can have upon other adjacent circuitry if this is not properly screened, filtered or otherwise
protected. Regulators, sensitive analogue circuitry, and microprocessors seem especially
interference prone.
Name
RF GND
Aerial
RF GND
Vcc
0V
TXE
RF GND
RF in/out
RF GND
Function
RF Ground
RF connection to aerial (50 Ω)
RF Ground
Regulated +5v supply, at <250mA
Supply Ground
Transmit mode enable (active low, 100K pullup to +5v)
RF Ground
RF connection to radio module
RF Ground
AFS2 data sheet
Page 2