Radiometrix Ltd, KTX2 Data Sheet

page 2

Functional and operational description

The KTX2 transmitter module is a crystal based PLL controlled FM code-hopping transmitter with a pre-

programmed Electronic Serial Number (ESN), operating between 3V and 6V supply, at 433.92MHz.

KTX2 is designed to meet or exceed EN 300 220-3 standards for European use and delivers nominally

+3dBm at 8mA (for 5V supply). The module measures 36.2 x 15.2 x 4.5 mm.

The module is very easy to use: there are no modulation input or transmitter-enable pins. The activation

of any combination of the four function lines (S0 – S3) causes a data transmission, part of which is the

status of S0 – S3, i.e. the function code. In this way, up to 15 different control combinations can be sent

from one module. Simple pushbuttons can be connected directly between S0 – S3 and Vcc if desired. The

module will transmit repeatedly whilst any of the function lines is held high for up to 30 seconds (approx.),

when a power-saving time-out feature is activated.

Vcc

(pin 4)

S0

(pin 5)

Input (0) – activate high (>0.55Vcc – Vcc) to cause a transmission.

S1

(pin 6)

Input (1) – activate high (>0.55Vcc – Vcc) to cause a transmission.

S2

(pin 7)

Input (2) – activate high (>0.55Vcc – Vcc) to cause a transmission.

S3

(pin 8)

Input (3) – activate high (>0.55Vcc – Vcc) to cause a transmission.

Internal Use (pin 9)

Modulation (Data). This pin is connected to the modulation input of the Transmitter, therefore do not

connect anything to this pin during operation of the module.

RF gnd

433.92 MHz

band pass

filter

buffer

1

RF out

Loop

Filter

Encoder

ref

osc

φ

5

2

supply

regulator

4

3 - 6Vcc

V C O

3

0V

6

7

8

9

S1

S0

S2

S3

Fig. 2: KTX2 block diagram

Pin description:

RF OUT

(pin 1)

50

Ω RF output to the antenna. Internally DC-

isolated. See antenna section of apps notes for

details of suitable antennas.

RF GND

(pin 2)

RF ground, internally connected to the module

screen and pin 3 (0V). This pin should be

directly connected to the RF return path - e.g.

coax braid, main PCB ground plane etc.

0V

(pin 3)

DC supply ground. Internally connected to pin

2 and module screen.

4.5 mm

36.2 mm

15.2

mm

15.7

mm

PCB level

Radiometrix

KTX2

9 holes, 0.7 mm dia, pin spacing 2.54 mm

Fig 3: KTX2 physical dimensions

15.24 mm

1

1 = RF OUT

2 = RF GND

3 = 0V

4 = Vcc

6 = S1

7 = S2

5 = S0

2

3

4

5

6

7

8

9

8 = S3

9 = Internal Use