MLX72013 Datasheet, PDF (12/21 Pages) Melexis Microelectronic Systems – FSK/ASK Transmitter

MLX72013
433MHz
FSK/ASK Transmitter
8.7 Output Power Steps – ASK Mode
If the transmitter IC is operated in ASK mode and at a power step lower than 4 then the ASK data signal
should be applied to pin PSEL via an additional resistor R1. Below table shows recommended component
values for resistors RPS and R1 for all power steps.
typical values at Ta = 23 °C and VCC = 3.3 V
Power step - PS
1
2
RPS / kΩ
2.4
2.8
R1 / kΩ
36
14
3
4
3.5
not connected
7
0
V_PSlow = voltage across RPS if ASK_DTA at 0V
V_PShigh = voltage across RPS if ASK_DTA at Vcc
V _{PS lo w}
RPS R1
PSEL
RPS
V_{PS high}
PS EL
R1
Vcc
If the transmitter is operated at any supply voltage V_cc, the values for R1 and RPS can be calculated as
follows:
R₁
=
V_CC ⋅V_PSlow
I _PSEL ⋅V_PShigh
R_PS
=
R₁
V_PShigh
V_CC − V_PShigh
3901072013
Rev. 007
Page 12 of 21
Data Sheet
Oct/14