TAS5100A

SLES030 − FEBRUARY 2002

7

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H-bridge output mapping (continued)

The B-side H-bridge output is designed to the following truth table:

INPUTS

OUTPUTS

DESCRIPTION

RESET

PWDN

PWM_BP

PWM_BM

SHUTDOWN

OUTPUTB

DESCRIPTION

X

X

X

X

0

0 or Hi-Z†

Shutdown

X

0

X

X

1

Hi-Z

Powerdown

0

1

X

X

1

0

Reset

1

1

0

0

0

0

Shutdown

1

1

0

1

1

0

Normal

1

1

1

0

1

1

Normal

1

1

1

1

0

0

Shutdown

† Output is 0 for low voltage, over temperature, or illegal input. Hi-Z is for over current.

control/sense circuitry

The control/sense circuitry consists of the following 3.3-V logic level pins: PWDN, RESET, ERR0, ERR1, and

SHUTDOWN. The active-low PWDN input pin powers down all internal circuitry and forces the H-bridge outputs

to the Hi-Z state. When the PWDN pin is low, the open drain ERR0, ERR1, and SHUTDOWN pins are also

disabled so that their outputs can be pulled high. The active-low RESET input pin forces the H-bridge outputs

to the low-low state and resets the over-current shutdown latch. The PWDN pin overrides the RESET pin. The

ERR0, ERR1, and SHUTDOWN outputs indicate the following conditions in the TAS5100A as shown in the table

below. These three outputs are open-drain connections with internal pullup resistors so that wire-ORed

connections can be made by the user with other external control devices. The short circuit protect error condition

latches the TAS5100A in this shutdown state and force the H-bridge outputs to the Hi-Z state until the device

is reset by means of the RESET pin. The illegal PWM input state, over-temperature, and low regulator voltage

error conditions do not latch the device in the shutdown condition. Instead the H-bridge outputs are forced to

the low-low state and the TAS5100A returns to normal operation as soon as the error condition ends. Loss of

clocking PWM signal is also considered an illegal PWM input state.

SHUTDOWN

ERR1

ERR0

FUNCTION

OUTPUTA

OUTPUTB

0

0

0

Illegal PWM input state

Low

Low

0

0

1

Short circuit protect (latch)

Hi-Z

Hi-Z

0

1

0

Over temperature protect

Low

Low

0

1

1

Low regulator voltage protect

Low

Low

1

0

0

Reserved

—

—

1

0

1

Reserved

—

—

1

1

0

High temperature − warning

Normal

Normal

1

1

1

Normal operation

Normal

Normal