Figure 3: LMT1 footpint (top view)
Pin description –
LMT1
Pin
1a
2a
3a
4a
5a
1b
2b
3b
4b
5b
Name
Vcc
0V
TXE
TXD
No pin
P0/PGM
P1
P2
P3
No pin
Function
3.1 – 15V power supply (10mW)
4.1V – 15V power supply (100mW)
Ground
Transmit Enable (active low)
DC coupled input for 3V CMOS logic. R
in
=47kΩ
Not present in LMT1
Parallel Channel select LSB
Serial frequency programming / configuration
1
Parallel Channel select
Parallel Channel select
Parallel Channel select MSB
Not present in LMT1
Notes:
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 (50kΩ) to 3v internal rail. Do not exceed 3V logic levels on
this port.
3. Channel select inputs are active low
4. TXE has a 100kΩ pullup to Vcc
5. All pins are on an 0.1" grid
6. The pins 5a/b are not present, but are included in footprint for compatibility with other units in
this family
7. In the 'off' state a PIN switch open circuits the RF output pin. There are no 'off' state spuri.
8. Unit will operate (with marginally reduced specifications and lower (6-8mW) output power)
from a 3.0V rail. This must be well regulated and without noise or ripple, as in this state the
unit's internal regulator no longer operates, and provides no supply rejection.
9. 100mW versions should not be run continuously from supply voltages > 9v
Radiometrix Ltd
LMT1/LMR1 Data Sheet
page 3
RADIOMETRIX [ RADIOMETRIX LTD ]
