L99PM72PXP datasheet(42/128 Pages) STMICROELECTRONICS

42 / 128 page

Protection and diagnosis

L99PM72PXP

42/128

Doc ID 023553 Rev 3

Protection and diagnosis

3.1

Power supply fail

Overvoltage and undervoltage detection on VS

3.1.1

VS overvoltage

If the supply voltage VS reaches the over voltage threshold (VSOV):

●

Outputs OUTx, RELx and LIN are switched to high impedance state (load protection).

CAN is not disabled. Recovery of outputs when the overvoltage condition disappears is

depending on the setting of VLOCK_OUT_EN bit in Control Register 4.

–

VLOCK_OUT_EN = 1: Outputs are off until read and clear SR3.

–

VLOCK_OUT_EN = 0: Outputs switch automatically on when overvoltage

condition disappears.

●

The over voltage bit is set and can be cleared with a ‘Read and Clear’ command. The

overvoltage bit is removed automatically if VLOCK_OUT_EN = 0 and the overvoltage

condition disappears.

●

Outputs REL1,2 can be excluded from a shutdown in case of overvoltage by SPI

(LS_OV/UV_shutdown_en in CR4)

3.1.2

VS undervoltage

If the supply voltage VS drops below the under voltage threshold voltage (VSUV)

●

Outputs OUTx, RELx and LIN are switched to high impedance state (load protection).

CAN is not disabled. Recovery of outputs when the undervoltage condition disappears

is depending on the setting of VLOCK_OUT_EN bit.

–

VLOCK_OUT_EN = 1: Outputs are off until read and clear SR3.

–

VLOCK_OUT_EN = 0: Outputs switch on automatically when undervoltage

condition disappears.

●

The undervoltage bit is set and can be cleared with a ‘Read and Clear’ command. The

undervoltage bit is removed automatically if VLOCK_OUT_EN = 0 and the

undervoltage condition disappears

●

Outputs REL1,2 can be excluded from a shutdown in case of undervoltage by SPI

(LS_OV/UV_shutdown_en in CR4)

L99PM72PXP Datasheet(PDF) 42 Page - STMicroelectronics

L99PM72PXP Datasheet(HTML) 42 Page - STMicroelectronics

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 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL