tle8242 Infineon Technologies Corporation, tle8242 Datasheet - Page 22

• Manufacturer Part Number: tle8242
• Description: 8 Channel Fixed Frequency Constant Current Control With Current Profile Detection
• Manufacturer: Infineon Technologies Corporation

Figure 9
5.3.1
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
V
V
V
V
V
V
POS
POS
POS
Masterclock
OL
SG
SB
PWM mode enabled
Gate is ON
PWM Start
Diagnostic Block Diagram
On-State Diagnostics
SG-FA
OL-FA
SB-FA
Gate On Counter
(only while OFF)
open load OFF
Divider Select
(SPI register)
digital filter
Predivider
1:128
1:192
1:256
1..64
short to ground
(only while OFF)
digital filter
(only while ON)
short to battery
clear
digital filter
(1..10) (shared)
fault filter timer
clear
clear
22
Functional Description and Electrical Characteristics
Tested timer
(shared)
1..10
clear
OL-OFF-FD
OL-ON-F
SG-FD
SB-FD
read SPI fault
LOGIC
register
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)
Rev. 1.0, 2009-02-25
TLE8242