DEMOTS4956J STMicroelectronics, DEMOTS4956J Datasheet - Page 39

• Manufacturer Part Number: DEMOTS4956J
• Description: BOARD DEMO TS4956EIJT/EIKJT
• Manufacturer: STMicroelectronics

Specifications of DEMOTS4956J

• Amplifier Type: Class AB
• Output Type: 1-Channel (Mono) with Mono and Stereo Headphones
• Max Output Power X Channels @ Load: 1W x 1 @ 8 Ohm; 43mW x 2 @ 32 Ohm
• Voltage - Supply: 2.7 V ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Board Type: Fully Populated
• Utilized Ic / Part: TS4956
• Description/function: Audio Amplifiers
• Operating Supply Voltage: 2.7 V to 5.5 V
• Product: Audio Modules
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With/related Products: TS4956
• Other names: 497-6381; DEMOTS4956J

TS4956
4.1.4
4.2
BTL output configuration (modes 1, 2, 7)
In a BTL (bridge tied load) output configuration (modes 1, 2 and 4), active outputs are
biased to the V
except for the MLO output, which is biased to V
BTL means that each end of the load is connected to two single-ended output amplifiers.
Therefore we have:
and
For the same power supply voltage, the output voltage amplitude is twice as high as the
output voltage in the single-ended or phantom ground configurations and the output power
is four times higher than the output power in the single-ended or phantom ground
configurations.
Power limitation in the phantom ground configuration
A power limitation is imposed on the headphones in mode 3 and 4. Limitation of output
power is achieved by limiting the output voltage and output current on each amplifier.
The maximum value of the output voltage, V
reach a maximum output power of the sinusoidal signal of around 40 mW per channel with a
32
The maximum value of output current I
maximum output power of the sinusoidal signal of around 40 mW per channel with a 16
load resistance and THD+N<1%.
limitation with different load resistances.
The maximum output power with these voltage and current limitations is reached with load
values above 16
Figure 123. Voltage and current limitation on headphones
Ω
single-ended output 1 = V
single-ended output 2 = V
V
load resistance and THD+N<1%.
out1
- V
out2
CC
Ω
= 2V
/2 voltage. All other inactive outputs are in the high impedance state
and below 32
Vpeak
out
MAX
(V)
=1.65V
Vout
out1
out2
Ω
Figure 48 on page 25
= V
= -V
as explained by
out
out
out max
(V)
(V)
out max
RL=32 Ohms
is set to value 70 mA in order to reach a
CC
/2 voltage.
, is set to a value of 1.65 V in order to
Figure
Ipeak
shows the functionality of the power
RL=24 Ohms
MAX
123.
=70mA
RL=16 Ohms
Application information
Iout
39/55
Ω