TDA5235
Functional Description
With this definition the Manchester duty cycle is calculated to
T1.chip chip + ΔT
T
MDCB = ---------------- = --------------------------
Tbit
Tbit
Edge delay Definition
MDC = Duration delayed edge / Symbol period
bit = 1
1
0
0
1
1. chip
2. chip
Tbit
T
chip
MDC < 50% T = 0
f
1
1
0
0
1
Tr
TH
Tr
TH
ΔT
T
Tbit
Tbit
Tbit
chip
MDC > 50% T = 0
r
1
1
0
0
1
Tf
Tf
ΔT
TH
TH
T
Tbit
Tbit
Tbit
chip
Figure 90
Definition C: Edge delay definition
This definition determinates the duty cycle to be the ratio of the duration of the delayed
high-chip and the ideal symbol period independently of the information bit content. The
position of the high-chip is determined by the delayed rising edge and/or the delayed
falling edge. For ΔT = Tfall -Trise the Manchester duty cycle is calculated to
TdelayedHighchip
MDCC = ---------------------------------------- = -------------------------- = -----------------------------------------------
Tbit Tbit Tbit
T
chip + ΔT
Tchip + Tfall – Trise
Independent on the bit content, the same type of edge (rising edge and/or falling edge)
is shifted.
Data Sheet
125
V1.0, 2010-02-19
INFINEON [ Infineon ]
