ata5279n ATMEL Corporation, ata5279n Datasheet - Page 9

• Manufacturer Part Number: ata5279n
• Description: Antenna Driver For Multiple Antennas
• Manufacturer: ATMEL Corporation

3.6.1
9125C–RKE–01/09
Functional Description of Diagnosis Mode
Beyond this, the diagnosis of all connected coil lines is a very useful tool for maintenance rea-
sons. The ATA5279N has implemented test structures that can be activated and read out via
SPI commands, so that the microcontroller can be programmed to detect most of the possible
faults, for example, shorts between different coil connection lines and multiple shorts in one pair
of lines.
In this diagnosis mode, the coil-line drivers themselves are switched to high impedance. Hence,
only the test structure at every coil connection (both at the positive outputs AxP of the drivers
and at the negative outputs AxN) is present and can directly test the status of the line.
illustrates this:
Figure 3-4.
The structure above can be found in each of the six channels of ATA5279N. As soon as the
diagnosis mode is engaged, all channels are operated in this way. On the channel that is actu-
ally selected, the setting of the switches can be changed with the Set Coil Current command and
the status of the two connection lines can be checked with the Get Driver Setup command.
The two switches in the P line driver are controlled with one bit. That means, either the high-side
(S_HxP) or the low-side (S_LxP) switch is closed. The same is true for the N line driver (S_HxN,
S_LxN). The controlling bits c
tion 3.9.2 “General Command Description” on page 20
Note that the setting of the switches is latched. That means, if the setting on the switches of the
selected driver is changed, the setting on the five other channels remains unchanged.
By a combination of test structures, many different faults, even between the coils, can be
detected.
c0 bit
Base Structure of the Diagnosis Module of One Output Channel
VDS
AGND
S_HxP
c0 = '1'
c0 = '0'
S_LxP
0
and c
1
are taken from the coil current selection register (see
AxP
c0, 1 bits
Latch
ATA5279N [Preliminary]
in this document).
AxN
Driver x select
S_HxN
c1 = '1'
c1 = '0'
S_LxN
AGND
VDS
c1 bit
Figure 3-4
Sec-
9