TDA8943SF - 6 W Mono Bridge Tied Load BTL Audio Amplifier

TDA8943SF
6 W mono Bridge Tied Load (BTL) audio amplifier
Rev. 02 — 7 April 2000 Product specification

1. General description
The TDA8943SF is a single-channel audio power amplifier with an output power of 6 W at an 8 ? load and a 12 V supply. The circuit contains a Bridge Tied Load (BTL) amplifier with an all-NPN output stage and standby/mute logic. The TDA8943SF comes in a 9-lead single in-line (SIL) medium power package. The TDA8943SF is printed-circuit board (PCB) compatible with all other types in the TDA894x family. One PCB footprint accommodates both the mono and the stereo products.

2. Features
s s s s s s s s s Few external components Fixed gain Standby and mute mode No on/off switching plops Low standby current High supply voltage ripple rejection Outputs short-circuit protected to ground, supply and across the load Thermally protected Printed-circuit board compatible.

c c

3. Applications
s Mains fed applications (e.g. TV sound) s PC audio s Portable audio.

4. Quick reference data
Table 1: VCC Iq Istb Quick reference data Conditions VCC = 12 V; RL = ? Min 6 Typ 12 15 Max 18 22 10 Unit V mA µA supply voltage quiescent supply current standby supply current Symbol Parameter

Philips Semiconductors

TDA8943SF
6 W mono Bridge Tied Load (BTL) audio amplifier
Quick reference data…continued Conditions THD = 10%; RL = 8 ?; VCC = 12 V Po = 1 W Min 5 31 50 Typ 6 0.03 32 65 Max 0.1 33 Unit W % dB dB output power total harmonic distortion voltage gain supply voltage ripple rejection

Table 1: Po THD Gv SVRR

Symbol Parameter

5. Ordering information
Table 2: Ordering information Package Name TDA8943SF SIL9MPF Description plastic single in-line medium power package with fin; 9 leads Version SOT110-1 Type number

6. Block diagram
idth

VCC 2

TDA8943SF
1 IN- IN+ 5 4 3 VCC MODE SVR 7 6 20 k? 8
MBK942

OUT-

OUT+

STANDBY/ MUTE LOGIC

20 k?

SHORT CIRCUIT AND TEMPERATURE PROTECTION

GND

Fig 1. Block diagram.

9397 750 06865

© Philips Electronics N.V. 2000. All rights reserved.

Product specification

Rev. 02 — 7 April 2000

2 of 20

Philips Semiconductors

TDA8943SF
6 W mono Bridge Tied Load (BTL) audio amplifier

7. Pinning information
7.1 Pinning
handbook, halfpage

OUT- VCC OUT+ IN+ IN- SVR MODE GND n.c.

1 2 3 4 5 TDA8943SF 6 7 8 9
MBK941

Fig 2. Pin configuration.

7.2 Pin description
Table 3: Symbol OUT- VCC OUT+ IN+ IN- SVR MODE GND n.c. Pin description Pin 1 2 3 4 5 6 7 8 9 Description negative loudspeaker terminal supply voltage positive loudspeaker terminal positive input negative input half supply voltage decoupling (ripple rejection) mode selection input (standby, mute, operating) ground not connected

8. Functional description
The TDA8943SF is a mono BTL audio power amplifier capable of delivering 6 W output power to an 8 ? load at THD = 10%, using a 12 V power supply and an external heatsink. The voltage gain is fixed at 32 dB. With the three-level MODE input the device can be switched from ‘standby’ to ‘mute’ and to ‘operating’ mode. The TDA8943SF outputs are protected by an internal thermal shutdown protection mechanism and a short-circuit protection.

9397 750 06865

© Philips Electronics N.V. 2000. All rights reserved.

Product specification

Rev. 02 — 7 April 2000

3 of 20

Philips Semiconductors

TDA8943SF
6 W mono Bridge Tied Load (BTL) audio amplifier

8.1 Input configuration
The TDA8943SF inputs can be driven symmetrical (floating) as well as asymmetrical. In the asymmetrical mode one input pin is connected via a capacitor to the signal ground which should be as close as possible to the SVR (electrolytic) capacitor ground. Note that the DC level of the input pins is half of the supply voltage VCC, so coupling capacitors for both pins are necessary. The input cut-off frequency is: 1 f i ( cut – off ) = ---------------------------2? ( R i × C i ) For Ri = 45 k? and Ci = 220 nF: 1 f i ( cut – off ) = ---------------------------------------------------------------- = 16 Hz 3 –9 2? ( 45 × 10 × 220 × 10 ) As shown in Equation 1 and 2, large capacitor values for the inputs are not necessary; so the switch-on delay during charging of the input capacitors, can be minimized. This results in a good low frequency response and good switch-on behaviour. Remark: To prevent HF oscillations do not leave the inputs open, connect a capacitor of at least 1.5 nF across the input pins close to the device. (2) (1)

8.2 Power amplifier
The power amplifier is a Bridge Tied Load (BTL) amplifier with an all-NPN output stage, capable of delivering a peak output current of 2 A. The BTL principle offers the following advantages:

• • • •
8.2.1

Lower peak value of the supply current The ripple frequency on the supply voltage is twice the signal frequency No expensive DC-blocking capacitor Good low frequency performance.

Output power measurement The output power as a function of the supply voltage is measured on the output pins at THD = 10%; see Figure 8. The maximum output power is limited by the maximum supply voltage of 12 V and the maximum available output current: 2 A repetitive peak current.