10XSC425 datasheet(37/56 Pages) FREESCALE

37 / 56 page

Analog Integrated Circuit Device Data



Freescale Semiconductor

10XSC425

6.3.1.3

Severe Short-circuit Fault

The 10XSC425 provides output shutdown to protect each output, in case of a severe short-circuit during the output switching.

If the short-circuit impedance is below RSHORT, the device will latch the output OFF, FSB will go to a logic [0] and the fault register

SC[0:3] bit will be set to [1]. To delatch the fault and be able to turn the outputs ON again, the failure condition must disappear,

and the corresponding output must be commanded OFF and then ON (toggling fault_control signal of corresponding output), or

VSUPPLY(POR) condition if VDD = 0.

The SPI fault report (SC[0:3] bits) is removed after a read operation.

6.3.1.4

Overvoltage Fault (Enabled by default)

By default, the overvoltage protection is enabled. The 10XSC425 shuts down all outputs and FSB will go to a logic [0] during an

overvoltage fault condition on the VPWR pin (VPWR > VPWR(OV)). The outputs remain in the OFF state until the overvoltage

condition is removed (VPWR < VPWR(OV) - VPWR(OVHYS)). When experiencing this fault, the OVF fault bit is set to logic [1] and

cleared after either a valid SPI read.

The overvoltage protection can be disabled through the SPI (OV_dis bit is disabled set to logic [1]). The fault register reflects any

overvoltage condition (VPWR > VPWR(OV)). This overvoltage diagnosis, as a warning, is removed after a read operation, if the fault

condition disappears. The HS[0:3] outputs are not commanded in RDS(ON) above the OV threshold.

6.3.1.5

Undervoltage Fault

The output(s) will latch off at some battery voltage below VPWR(UV). As long as the VDD level stays within the normal specified

range, the internal logic states within the device will remain (configuration and reporting).

In the case where battery voltage drops below the undervoltage threshold (VPWR < VPWR(UV)), the outputs will turn off, FSB will

go to logic [0], and the fault register UV bit will be set to [1].

Two cases need to be considered when the battery level recovers (VPWR > VPWR(UV)_UP):

• If the output command is low, FSB will go to a logic [1], but the UV bit will remain set to 1 until the next read operation

(warning report).

• If the output command is ON, FSB will remain at logic [0]. To delatch the fault and be able to turn the outputs ON again, the

failure condition must disappear and the autoretry circuitry must be active, or the corresponding output must be commanded

OFF and then ON (toggling fault_control signal of corresponding output), or a VSUPPLY(POR) condition, if VDD = 0.

In extended mode, the output is protected by overtemperature shutdown circuitry. All previous latched faults, occurred when

VPWR is within the normal voltage range, are guaranteed if VDD is within the operational voltage range, or until VSUPPLY(POR), if

VDD = 0. Any new OT fault is detected (VDD failure included) and reported through SPI above VPWR(UV). The output state is

not changed, as long as the VPWR voltage does not drop any lower than 3.5 V (typical).

All latched faults (overtemperature, overcurrent, severe short-circuit, over and undervoltage) are reset if:

•VDD < VDD(FAIL) with VPWR in nominal voltage range,

•VDD and VPWR supplies is below the VSUPPLY(POR) voltage value.

Over-current thresholds

toff

depending to toff

Cooling

PWM

hson signal

fault_control

hson

Depending on toff

10XSC425 Datasheet(PDF) 37 Page - Freescale Semiconductor, Inc

10XSC425 Datasheet(HTML) 37 Page - Freescale Semiconductor, Inc

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56

Datasheet Download

Link URL