TDF8599ATH データシートの表示（PDF） - NXP Semiconductors.

部品番号

コンポーネント説明

メーカー

TDF8599ATH

I2C-bus controlled dual channel 135 W/4Ω, single channel 250 W/2Ω class-D power amplifier with load diagnostics

NXP Semiconductors. 

NXP Semiconductors

TDF8599A

I2C-bus controlled dual channel class-D power amplifier

PWM

CONTROL

DRIVER

HIGH

DRIVER

LOW

PWM

CONTROL

DRIVER

HIGH

DRIVER

LOW

Fig 16. DC load detection circuit

VP

B

OUTN

PGND1

VP

OUTP

PGND2

RL

001aai787

out (V)

out−

out+

td(stb-mute)

tdet(DCload)

t (s)

001aai788

Fig 17. DC load detection procedure

The capacitor connected to pin SEL_MUTE (see Figure 3 on page 6) is used to create an

inaudible current test pulse, drawn from the positive amplifier output. The diagnostic

‘speaker load’ (or ‘open load’), based on the voltage difference between pins OUTxP and

OUTxN is shown in Figure 18.

SPEAKER LOAD

OPEN LOAD

0Ω

25 Ω 350 Ω

001aaj956

Fig 18. DC load detection limits

Remark: DC load detection identifies a short circuited speaker as a valid speaker load.

OCP detection, using byte DB1[D3] for channel 1 and byte DB2[D3] for channel 2,

performs diagnostics on shorted loads. However, the diagnostics are performed after the

DC load detection cycle has finished and once the amplifier is in Operating mode.

The result of the DC load detection is stored in bits DB1[D4] and DB2[D4].

TDF8599A_2

Product data sheet

Rev. 02 — 30 June 2009

© NXP B.V. 2009. All rights reserved.

19 of 54

Share Link: