TLE8242-2 Datasheet, PDF (22/78 Pages) Infineon Technologies AG – 8 Channel Fixed Frequency Constant Current Control With Current Profile Detection

TLE8242-2
Divider Select
(SPI register)
Functional Description and Electrical Characteristics
read SPI fault
register
Masterclock
V_POS
V_OL
OL-FA
V_POS
V_SG
SG-FA
V_POS
V_SB
SB-FA
PWM mode enabled
PWM Start
Gate is ON
Predivider
1:128
1:192
1:256
fault filter timer
(1..10) (shared)
clear clear clear
digital filter
open load OFF
(only while OFF)
digital filter
short to ground
(only while OFF)
digital filter
short to battery
(only while ON)
Tested timer
1..10
(shared)
clear
LOGIC
OL-OFF-FD
SG-FD
SB-FD
OL-ON-F
SG-F (Short to Ground Fault)
OFF-T (Short to Ground and Open
Load Off Tested)
SB-F (Short to Battery Fault)
SB-T (Short to Battery Tested)
OL-OFF-F (Open Load Off Fault)
OL-ON-F (Open Load On Fault)
Gate On Counter
1..64
Figure 9 Diagnostic Block Diagram
5.3.1 On-State Diagnostics
When the OUTx pin transitions high, the fault timers are cleared to 0 and the tested timer starts. If the tested timer
expires, the Bit SB-T (in the SPI registers #4 and #5) is set to 1. If the OUTx pin transitions low, the tested timer
is cleared and then used for the off-state diagnostics.
If the analog SB fault signal (SB-FA) changes to 1, the fault filter timer starts. If the fault filter timer expires, the
digitally filtered SB fault signal (SB-FD) is set to one. If SB-FA changes to 0, SB-FD changes immediately to 0 and
the filter timer is cleared to 0.
A SB-FD=1 and SB-T=1 switches off the OUTx signal and the SB-F bit in the FAULT register will be set. The OUTx
pin remains in the off state until the fault retry PWM period counter expires.
If the SPI message #3 or #4 is read, then the SB-F bit and the SB-FT bit in this register are cleared. Also, the tested
timer is cleared to 0.
The Short to Battery (SB) detection functions in both direct PWM and constant current mode. The SG-FD and OL-
OFF-FD signals are held to 0 while the OUTx pin is high.
If the TLE8242 IC is in direct PWM mode, Open Load ON detection is disabled (OL-ON-F = 0).
If the TLE8242 IC is not in direct PWM mode and the OUTx pin is high for 64 PWM periods, then the open load
fault ON mode fault is detected, and the OL-ON-F bit in the diagnostic register is set. This bit will be cleared when
SPI message #3 or #4 is read. If the OUTx pin remains in a high state, then the open load - on fault condition is
detected again after another 64 PWM cycles.
Data Sheet
22
Rev. 1.0, 2010-02-09