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© Koninklijke Philips Electronics N.V. 2004. All rights reserved.

Objective data sheet

Rev. 01 — 22 April 2004

7 of 21

Philips Semiconductors

TDA8939

Zero dead time Class-D 7.5 A power comparator

8.3.2 Outputs

8.3.3 Reference voltages

8.4

Start-up timing

Power comparator mode selection:

mode, independent of the signal on the enable input

controlled by pin ENABLE; if pin ENABLE is LOW, the status of the power stage is

reset and the outputs are floating

To ensure correct start-up of the power stage, the enable input should never be HIGH

when the power-up input is LOW. Before switching to operating mode, the amplifier should

first be switched to reset mode.

Remark: It is possible to directly connect the power-up input to the positive supply line

mode).

Table 5:

Outputs

Pin name

Pin number

Description

DIAGN

7

Digital open-drain output; referenced to CGND; output indicates

the following fault conditions: OTP, OCP, OVP and UVP. In the

event of a fault condition the output is pulled to the CGND voltage

(active LOW). If the diagnostic output functionality is used in the

application, an external pull-up resistor is required.

Table 6:

Reference voltages

Pin name

Pin number

Description

CGND

8

common ground; reference ground for diagnostic

output, enable input and power-up input

24

negative digital supply; reference ground digital circuits.

protection diode.

Table 7:

Mode selection

Pin

Mode

POWERUP

ENABLE

LOW

X

standby

HIGH

LOW

reset

HIGH

HIGH

operating