ATA5749-EK2 Atmel, ATA5749-EK2 Datasheet - Page 13

• Manufacturer Part Number: ATA5749-EK2
• Description: BOARD EVALUATION TPMS 433MHZ
• Manufacturer: Atmel
• Type: Transmitterr

Specifications of ATA5749-EK2

• Frequency: 433MHz
• For Use With/related Products: ATA5749
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

6.2
Figure 6-1.
Figure 6-2.
9128G–RKE–03/11
Programming
SDIN_TXDIN
SDIN_TXDIN
CLK (Output)
SCK (Input)
PA (Output
EN (Input)
SPI Bus Timing
Timing Diagram if Register Programming is Faster than T
Power)
(Input)
SCK
EN
OFF_
Mode
The configuration register is programmed serially using the SPI bus, starting with the MSB. It
consists of the Enable line (EN), the Data line (SDIN_TXDIN), and the SPI-Bus Clock (SCK).
The SDIN_TXDIN data is loaded on the positive edge of the SCK. The contents of the configura-
tion register become programmed on the negative SCK edge of the last bit (LSB) of the
programming sequence. The timing of this bus is shown in
usable clock speed on the SPI bus is limited to 2MHz.
At the conclusion of the 32 bit programming sequence, the SDIN_TXDIN line becomes the
modulation input for the RF transmitter. After programming is complete, the SCK signal has no
effect on the device. To disable the transmitter and enter the OFF Mode, EN and SDIN_TXDIN
must be returned to the LOW state. For clarity, several additional timing diagrams are included.
Figure 6-2
T
T
Setup
EN_setup
Start_Up_
Mode_1
shows the situation when the programming terminates faster then the XTO is ready.
MSB
T
T
Hold
SCK_High
32-bit Configuration
T
XTO
Start_Up_
T
Mode_2
SCK_Cycle
X
T
SCK_Low
MSB-1
XTO
X
Mode1
T
TX_
PLL
X
X
TX_Mode1 and
Figure
TX_Mode2
TX_Mode2
TX-Data
FSK;
ASK:
T
Atmel ATA5749
SDIN_TXDIN_setup
6-1. Note that the maximum
X
OFF_Mode
13