AN3352

Block diagram and pin function description

Doc ID 018526 Rev 3

9/26

Figure 5.

LNBH24L pin configuration

Table 3.

LNBH24L pin description

QFN 5x5

pin n°

Symbol

Name

Pin function

21

Supply input

8 to 15 V IC DC-DC power supply

20

Supply input

8 to 15 V analog power supply

5/2

LX-A /

LX-B

NMos drain

Integrated N-channel power MOSFET drain

16/25

Step-up voltage

Input of the linear post-regulator. The voltage on this pin is monitored

by the internal step-up controller to keep a minimum dropout across

the linear pass transistor.

18/23

LDO output port

Output of the linear post-regulator

17/24

Output port during

22 kHz tone TX

TX output to the LNB

6

SDA

Serial data

Bi-directional data from/to the I²C bus

7

SCL

Serial clock

Clock from the I²C bus

10/31

DSQIN-A/

DSQIN-B

DiSEqC input

This pin accepts the DiSEqC code from the main microcontroller. The

LNBH24L uses this code to modulate the internally-generated 22 kHz

carrier. Set this pin to ground if not used.