
SX1240
Integrated Transmitter IC
ADVANCED COMMUNICATIONS & SENSING
DATASHEET
Symbol
T_START
Description
Time before CTRL pin mode
Conditions
Time from power on to sampling of
Min
-
Typ
200 us
Max
-
Unit
ms
selection.
CTRL ***
+ TS_OSC
*
**
***
Frequency deviation is positive (+FDA) with DATA = ‘1’, negative (-FDA) with DATA = ‘0’
With two different matching networks
The oscillator startup time, TS_OSC, depends on the electrical characteristics of the crystal
**** Ramp-up time of the internal regulator turning the PA on. The typical 10% - 90% power ramp-up time is 10us
2.5. Timing Characteristics
The following table gives the operating specifications for the TWI interface of the SX1240.
Table 5
Serial Interface Timing Specifications
Symbol
f ctrl
t ch
t cl
t rise
t fall
t setup
t hold
Description
CTRL Clock Frequency
CTRL Clock High time
CTRL Clock Low time
CTRL Clock rise time
CTRL Clock Fall time
DATA Setup time
DATA hold time
Conditions
From Data transition to CTRL rising
edge
From CTRL rising edge to DATA
transition
Min
-
45
45
-
-
45
45
Typ
-
-
-
-
-
-
-
Max
10
-
-
5
5
-
-
Unit
MHz
ns
ns
ns
ns
ns
ns
SX1240, Rev 1, Oct 2010
?2010 Semtech Corp.
Page 7
www.semtech.com