Radiometrix Ltd

LMT2/LMR2 Data Sheet

page 3

Pin description – LMT2

Pin

Name

Function

1a

Vcc

3.1 – 15V power supply (@ 10mW)

4.1 – 15V power supply (@ 100mW)

2a

0V

Ground

3a

TXE

Transmit Enable (active low)

4a

TXD

Ω

5a

No pin

Not present in LMT2

1b

P0/PGM

Parallel Channel select LSB

2b

P1

Parallel Channel select

3b

P2

Parallel Channel select

4b

P3

Parallel Channel select MSB

5b

No pin

Not present in LMT2

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 (50k

Ω) to 3v internal rail. Do not exceed 3V logic levels on

this port.

3. Channel select inputs are active low

4. TXE has a 100k

Ω 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. 10mW 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

Figure 3: LMT2 footpint (top view)