Data Sheet

13

Rev. 1.0, 2008-10-30

TLE7239GS

Power Supply

5

Power Supply

The TLE7239GS is supplied by two supply voltages

V

feed and used by the power switches and by an integrated power supply for the register banks. The internal power

supply is designed to hold the state of the power switches including the configuration stored in the control register

bank during cranking down to 4V.There is an under voltage reset function implemented for the

V

After start-up of the power supply, all SPI registers are reset to their default values and the device is in sleep mode

(standby). The SPI command CMD.WAKE = 1 is switching the device to operation mode (ON), while a command

CMD.STB = 1 send the device to sleep mode (standby) again.

The

V

daisy chain function is available as soon as

V

between pins

V

5.1

Operation Modes

There is a limp home functionality implemented in the TLE7239GS, which is activated via pin LHI. Please refer to

Section 5.2 for details.

The device provides a sleep mode (stand by) to minimize current consumption, which also resets the register

banks. It is entered and left by dedicated SPI commands .The sleep mode current is minimized only when limp

home is inactive. After limp home, the device enters sleep mode automatically.

The internal power supply is designed for low voltage cranking condition down to

V

output channels keep their state as before configured via SPI independent of

V

SPI can not be used as the output and input levels refer to

V

the limp home mode is triggered or the

V

The following table shows the operation modes depending on

V

5.2

Limp Home Mode

The TLE7239GS offers the capability of driving dedicated channels during fail-safe operation of the system. This

limp home mode is activated by a high signal at pin LHI. In limp home mode, the SPI registers are reset and the

input pins are directly routed to the auto configuring channels (channel 4 and 5). As a result, the limp home

operation can be chosen for high-side and low-side driven loads.

Due to the integrated power supply, limp home operation is independent of digital power supply

V

stand-by, a high signal at pin LHI will wake up the device. After limp home operation, the device enters sleep mode

in any case.

Operation Modes

VBB

0V

0V

0V

4V

4V

4V

12 V

12V

12 V

12 V

VDD

0 V5 V

5 V0 V

0 V3 V

0 V0 V5 V

5 V

LHI

X

0V

5V

0V

4V

0V

0V

5V

0V

5V

Switches operating

-

-

-

✓✓

✓✓

✓

✓

✓

Limp Home

-

-

-

-

✓

--

✓

-

✓

SPI & daisy-chain

-

✓

✓

--

✓

--

✓

✓

Register Banks

reset

reset

reset

✓

reset

✓

✓

reset

✓

reset

Diagnostic functions

-

-

-

-

-

-

✓

-

✓

-