Data Sheet TLE 6240 GP

V3.1

Page

26.Aug 2002

7

Functional Description

The TLE 6240 GP is an 16-fold low-side power switch which provides a serial peripheral in-

terface (SPI) to control the 16 power DMOS switches, and diagnostic feedback. The power

voltage by active zener clamp.

The diagnostic logic recognizes a fault condition which can be read out via the serial diagnos-

tic output (SO).

Circuit Description

Power Transistor Protection Functions

7)

Each of the 16 output stages has its own zener clamp, which causes a voltage limitation at the

power transistor when solenoid loads are switched off. The outputs are provided with a current

limitation set to a minimum of 1 A for channels 1 to 8 and 3 A for channels 9 to16.

Each output is protected by embedded protection functions. In the event of an overload or

short to supply, the current is internally limited and the corresponding bit combination is set

(early warning). If this operation leads to an overtemperature condition, a second protection

level (about 170 °C) will change the output into a low duty cycle PWM (selective thermal shut-

down with restart) to prevent critical chip temperatures.

SPI Signal Description

CS

pin. Whenever the pin is in a logic low state, data can be transferred from the µC and vice

versa.

CS

High to Low transition: - Diagnostic status information is transferred from the power

outputs into the shift register.

- Serial input data can be clocked in from then on.

- SO changes from high impedance state to logic high or low

state corresponding to the SO bits.

CS

Low to High transition: - Transfer of SI bits from shift register into output buffers

.

To avoid any false clocking the serial clock input pin SCLK should be logic low state during

pins are ignored and SO is forced into a high impedance state.

SCLK - Serial Clock. The system clock pin clocks the internal shift register of the TLE

6240 GP. The serial input (SI) accepts data into the input shift register on the falling edge of

SCLK while the serial output (SO) shifts diagnostic information out of the shift register on the

7 )

The integrated protection functions prevent an IC destruction under fault conditions and may not be used in normal operation or perma-

nently