HMT2 Datasheet, PDF (3/7 Pages) Radiometrix Ltd – NBFM Multi-channel 500mW UHF Transmitter

Figure 3: HMT2 Footprint (Top) view through can
User Interface
Pin description
Pin
Name
1a
Vcc
2a
0V
3a
0V
4a
0V
5a
RF input
6a
0V
Function
5v regulated power supply (high current feed)
Ground
Ground
Ground
50Ω RF input from the antenna
Ground
1b
P0/PGM
Channel select LSB / Serial programming (inverted logic level rs232)
2b
P1
Channel select
3b
P2
Channel select
4b
P3
Channel select MSB
5b
Vcc
5v input (low current feed)
6b
TXE
Transmitter enable. Low = ON, open = off. 100K pullup to Vcc
7b
0V
Ground
8b
Notes:
TXD
DC coupled input for 3V CMOS logic. R_in=47kΩ
1. Serial programming is by an inverted, cmos logic level, 2400 baud RS232 datastream applied to the
P0 pin.
2. Channel select inputs have pullups (50K) to 4v internal rail. Do not exceed 4v logic levels on this
port.
3. Channel select inputs are active low
4. TXE has a 100K pullup to Vcc
5. All pins are on an 0.1" grid
6. Pin 1a supplies the power amplifer. This pin requires a clean, well regulated 5v supply at up to
300mA
Pin 5b supplies the remainder of the module. It can tolerate 4.1-9v and draws up to 100mA
7. A version of the design is available with an LDO regulator in the PA feed.
In this case pin 1a can be supplied from a 6-9v rail too
8. Pinout is compatible with FPX3, SHX1 and UHX1 transceivers, although the case is narrower and
the pins associated with receive functionality are absent.
Radiometrix Ltd
HMT2 Data Sheet
page 3