|
|
PDF TFA9841J Data sheet ( Hoja de datos )
| Número de pieza | TFA9841J | |
| Descripción | 1-channel audio amplifier | |
| Fabricantes | NXP Semiconductors | |
| Logotipo |  |
|
Hay una vista previa y un enlace de descarga de TFA9841J (archivo pdf) en la parte inferior de esta página. Total 17 Páginas | ||
|
No Preview Available !
TFA9841J
1-channel audio amplifier (SE: 1 W to 7.5 W)
Rev. 01 — 06 February 2004
Preliminary data
1. General description
The TFA9841J contains one audio power amplifier. The TFA9841J can be used as
one Single-Ended (SE) channel with a fixed gain of 26 dB.
The TFA9841J comes in a 9-pin DIL-bent-SIL (DBS9P) power package. The
TFA9841J is pin compatible with the TFA9842J and TFA9843J.
The TFA9841J contains a unique protection circuit that is solely based on multiple
temperature measurements inside the chip. This gives maximum output power for all
supply voltages and load conditions with no unnecessary audio holes. Almost any
supply voltage and load impedance combination can be made as long as thermal
boundary conditions (external heatsink and ambient temperature) allow it.
2. Features
s SE: 1 W to 7.5 W (into 4 Ω), up to 9 W into (into 8 Ω)
s Soft clipping
s Standby and mute mode
s No on/off switching plops
s Low standby current
s High supply voltage ripple rejection
s Outputs short-circuit protected to ground, supply and across the load
s Thermally protected
s Pin compatible with the TFA9842J and TFA9843J.
3. Applications
s Television
s PC speakers
s Boom box
s Mini and micro audio receivers.
1 page  
Philips Semiconductors
TFA9841J
1-channel audio amplifier (1 x SE)
Standby — The current consumption is very low and the output is floating. The
device is in standby mode when VMODE < 0.8 V, or when pin MODE is grounded.
Mute — The amplifier is DC-biased but not operational (no audio output). This allows
the input coupling capacitors to be charged to avoid pop-noise. The device is in mute
mode when 4.5 V < VMODE < (VCC − 3.5 V).
On — The amplifier is operating normally. The operating mode is activated at
VMODE > (VCC − 2.0 V).
standby
mute
on
0.8 4.5
Fig 3. Mode selection.
VCC−3.5 VCC−2.0 VCC
VMODE (V)
MDB797
8.4 Supply voltage ripple rejection
The supply voltage ripple rejection (SVRR) is measured with an electrolytic capacitor
of 150 µF on pin SVR using a bandwidth of 20 Hz to 22 kHz. Figure 10 illustrates the
SVRR as function of the frequency. A larger capacitor value on pin SVR improves the
ripple rejection behavior at the lower frequencies.
8.5 Built-in protection circuits
The TFA9841J contains two types of temperature sensors; one measures local
temperatures of the power stage and one measures the global chip temperature. At a
local temperature of the power stage of approximately 185 oC or a global temperature
of approximately 150 oC, this detection circuit switches off the power stage for 2 ms.
High impedance of the output is the result. After this time period, the power stage
switches on automatically and the detection will take place again; still a too high
temperature switches off the power stage immediately. This protects the TFA9841J
against shorts to ground, to the supply voltage, across the load and too high chip
temperatures.
The protection will only be activated when necessary, so even during a short-circuit
condition, a certain amount of (pulsed) current will still be flowing through the short,
just as much as the power stage can handle without exceeding the critical
temperature level.
9397 750 12014
Preliminary data
Rev. 01 — 06 February 2004
© Koninklijke Philips Electronics N.V. 2004. All rights reserved.
5 of 17
5 Page 
Philips Semiconductors
TFA9841J
1-channel audio amplifier (1 x SE)
AUDIO POWER CS NIJMEGEN
PF / 3002 .naJ 72
TVA
TFA9843J
100 nF
220
nF
CIV
22
µF SGND
CIV
IN2+
220
nF
IN1+
1000 µF
150 µF
+VP
MODE
10
kΩ
10 kΩ
SB ON
MUTE
MCE506
Fig 12. Printed-circuit board layout (single-sided); components view.
13.1.2 Power supply decoupling
Proper supply bypassing is critical for low-noise performance and high supply voltage
ripple rejection. The respective capacitor location should be as close as possible to
the device and grounded to the power ground. Proper power supply decoupling also
prevents oscillations.
For suppressing higher frequency transients (spikes) on the supply line a capacitor
with low ESR, typical 100 nF, has to be placed as close as possible to the device. For
suppressing lower frequency noise and ripple signals, a large electrolytic capacitor,
e.g. 1000 µF or greater, must be placed close to the device.
The bypass capacitor on pin SVR reduces the noise and ripple on the mid rail
voltage. For good THD and noise performance a low ESR capacitor is recommended.
9397 750 12014
Preliminary data
13.2 Thermal behavior and heatsink calculation
The measured maximum thermal resistance of the IC package, Rth(j-mb), is 4.0 K/W.
A calculation for the heatsink can be made, with the following parameters:
Tamb(max) = 60 °C (example)
VCC = 18 V and RL = 4 Ω
Tj(max) = 150 °C (specification)
Rth(tot) is the total thermal resistance between the junction and the ambient including
the heatsink. This can be calculated using the maximum temperature increase
divided by the power dissipation:
Rth(tot) = (Tj(max) − Tamb(max))/PD
Rev. 01 — 06 February 2004
© Koninklijke Philips Electronics N.V. 2004. All rights reserved.
11 of 17
11 Page | ||
| Páginas | Total 17 Páginas | |
| PDF Descargar | [ Datasheet TFA9841J.PDF ] | |
Hoja de datos destacado
| Número de pieza | Descripción | Fabricantes |
| TFA9841J | 1-channel audio amplifier | NXP Semiconductors |
| Número de pieza | Descripción | Fabricantes |
| SLA6805M | High Voltage 3 phase Motor Driver IC. |
 Sanken |
| SDC1742 | 12- and 14-Bit Hybrid Synchro / Resolver-to-Digital Converters. |
 Analog Devices |
|
DataSheet.es es una pagina web que funciona como un repositorio de manuales o hoja de datos de muchos de los productos más populares, |
| DataSheet.es | 2020 | Privacy Policy | Contacto | Buscar |