TLE6712G Infineon Technologies, TLE6712G Datasheet - Page 7

• Manufacturer Part Number: TLE6712G
• Manufacturer: Infineon Technologies

Specifications of TLE6712G

• Packages: P-DSO-24

The transfer of a 16 Bit command word starts with the falling CSN signal. At this time the
CLK signal must be high. The DI signal must be valid during rising edge of the CLK
signal. The transmission ends after the 16th rising edge of CLK and when the CSN signal
becomes high again. The left side of Figure 3 shows a correct transmission of a 16 Bit
command. On the right side you can see a incorrect transmission. CSN signal returns
high too late. A clock failure occurs and all latched data is be disregarded.
Figure 3
2.3
The Dual Firing Airbag IC includes two independent driver circuits. Every driver circuit
consists of a high- and a low-side DMOS switch. Between these switches a squib can
be connected in series.
The two driver circuits are designed as follows. The Drain of the high-side switch is
connected to the Firing Voltage pin FV12 and its source to the output pin squib high- side
x (SQHx (x=1, 2)). The drain of the low-side switch is connected to the input pin squib
low-side x (SQLx (x=1, 2) and the source is connected to the ground pin for the firing loop
(GNDLx (x=1, 2)). This is illustated in Block Diagram Squib Driver Circuit on page 8.
The squib will only be fired if all of the following signals are present correctly: SPI firing
command, RI, FEN, and SEN.
RI, FEN (Firing Enable) and SEN are external inputs which must be HIGH to enable
firing. When activating the low-side transistor the firing current will be sensed and latched
for all two squibs. If the current exceeds the firing current detection level, a bit will be set
and latched. This bit will then be read out at pin MO by the micro controller after the SPI
command firing current detection (see Chapter 3.5 DXXX
High Current Detection) is sent. If the programed channel has fired, the MO pin has low
output voltage. All the latches will be reset when the special SPI command (FFFF
DXXX
Company Confidential
RI
CSN
CLK
DI
H
see Chapter 3) is sent or when the device is reset via external pin RI = low.
Squib Drivers
Timing of the Serial Peripheral Interface (SPI)
MSB
1
2
3
4
14
7
15
LSB
16
H
MSB
: Channel Selection for
1
V 1.61 2001-07-13
16
17
TLE 6712
AET02609
Clock
Failure
H
or