TDA7266D ,5W+5W DUAL BRIDGE AMPLIFIERTDA7266D5W+5W DUAL BRIDGE AMPLIFIERPRELIMINARY DATA■ WIDE SUPPLY VOLTAGE RANGE (3.5 - 12V)TECHNOLOG ..
TDA7266D13TR ,7+7W DUAL BRIDGE AMPLIFIERELECTRICAL CHARACTERISTICS (V = 11V, R = 8Ω, f = 1kHz, T = 25°C unless otherwiseCC L ambspecified.) ..
TDA7266L ,5W MONO BRIDGE AMPLIFIERELECTRICAL CHARACTERISTICS (Continued)Symbol Parameter Test Condition Min. Typ. Max. UnitVT St-by T ..
TDA7266M ,7W MONO BRIDGE AMPLIFIERELECTRICAL CHARACTERISTICS (V = 11V, R = 8Ω, f = 1kHz, T = 25°C unless otherwiseCC L ambspecified.) ..
TDA7266P ,3+3W Dual Bridge AmplifierFEATURESFigure 1. Package■ TECHNOLOGY BI20II■ WIDE SUPPLY VOLTAGE RANGE (3.5 - 12V)■ OUTPUT POWER:– ..
TDA7266P13TR ,3 W + 3 W dual bridge amplifierFEATURESFigure 1. Package■ TECHNOLOGY BI20II■ WIDE SUPPLY VOLTAGE RANGE (3.5 - 12V)■ OUTPUT POWER:– ..
THC63LVD1024 , 135MHz 67Bits LVDS Receiver
THC63LVD104 , 90MHz 30Bits COLOR LVDS Receiver
THC63LVD823B , 160MHz 51Bits LVDS Transmitter
THC63LVDM83D , REDUCED SWING LVDS 24Bit COLOR HOST-LCD PANEL INTERFACE
THC63LVDM83D , REDUCED SWING LVDS 24Bit COLOR HOST-LCD PANEL INTERFACE
THC63LVDM87 , LOW POWER / SMALL PACKAGE / 24Bit COLOR LVDS TRANSMITTER
TDA7266D
5W+5W DUAL BRIDGE AMPLIFIER
1/13
TDA7266DMay 2003 WIDE SUPPLY VOLTAGE RANGE (3.5 - 12V) OUTPUT POWER
5+5W @THD = 10%, RL = 8Ω, VCC = 9.5V SINGLE SUPPLY MINIMUM EXTERNAL COMPONENTS NO SVR CAPACITOR NO BOOTSTRAP NO BOUCHEROT CELLS INTERNALLY FIXED GAIN STAND-BY & MUTE FUNCTIONS SHORT CIRCUIT PROTECTION THERMAL OVERLOAD PROTECTION
DESCRIPTIONThe TDA7266D is a dual bridge amplifier specially
designed for LCD TV/Monitor, PC Motherboard, TV
and Portable Audio applications.
PRELIMINARY DATA5W+5W DUAL BRIDGE AMPLIFIER
TEST AND APPLICATION CIRCUIT
TDA7266D 2/13
ABSOLUTE MAXIMUM RATINGS
THERMAL DATANotes:1. See Application note AN668, available on WEB FR4 with 15 via holes and ground layer.
PIN CONNECTION
3/13
TDA7266D
ELECTRICAL CHARACTERISTCS (Refer to test circuit) VCC = 9.5V, RL = 8Ω, f = 1KHz, Tamb = 25°C unlessotherwise specified)
TDA7266D 4/13
APPLICATIVE SUGGESTIONSSTAND-BY AND MUTE FUNCTIONS
(A) Microprocessor ApplicationIn order to avoid annoying "Pop-Noise" during Turn-On/Off transients, it is necessary to guarantee the right St-
by and mute signals sequence.It is quite simple to obtain this function using a microprocessor (Fig. 1 and 2).
At first St-by signal (from μP) goes high and the voltage across the St-by terminal (Pin 9) starts to increase ex-
ponentially. The external RC network is intended to turn-on slowly the biasing circuits of the amplifier, this to
avoid "POP" and "CLICK" on the outputs.
When this voltage reaches the St-by threshold level, the amplifier is switched-on and the external capacitors in
series to the input terminals (C1, C3) start to charge.
It's necessary to mantain the mute signal low until the capacitors are fully charged, this to avoid that the device
goes in play mode causing a loud "Pop Noise" on the speakers.
A delay of 100-200ms between St-by and mute signals is suitable for a proper operation.
Figure 1. Microprocessor Application
5/13
TDA7266D
Figure 2. Microprocessor Driving Signals
B) Low Cost ApplicationIn low cost applications where the mP is not present, the suggested circuit is shown in fig.3.
The St-by and mute terminals are tied together and they are connected to the supply line via an external voltage
divider.
The device is switched-on/off from the supply line and the external capacitor C4 is intended to delay the St-by
and mute threshold exceeding, avoiding "Popping" problems.
So to avoid any popping or clicking sond, it is important to clock:
Correct Sequence: At turn-ON, the Stand-by must be removed at first, then the Mute must be re-leased after a delay of about 100-200ms. On the contrary at turn-OFF the Mute must be activated
as first and then the Stand-by.
With the values suggested in the Application circuit the right operation is guaranteed.
Correct Threshold Voltages: In order to avoid that due to the spread in the internal thresholds (seethe above limits) a wrong external voltage causes uncertain commutations for the two functions we
suggest to use the following values:
Mute for Vcc>6.4V : VT = 2.3V
Mute for Vcc<6.4V : VT = Vcc/2 - 1
Stand-by : VT = 0.8V
TDA7266D 6/13
Figure 3. Stand-alone low-cost Application
PCB Layout and External Components: Regarding the PCB layout care must be taken for three main subjects:
c) Signal and Power Gnd separation
d) Dissipating Copper Area
e) Filter Capacitors positioning
)Signal and Power Gnd separation: To the Signal GND must be referred the Audio Input Signals, the Mute and Stand-by Voltages and
the device PIN.13. This Gnd path must be as clean as possible in order to improve the device
THD+Noise and to avoid spurious oscillations across the speakers.
The Power GND is directly connected to the Output power Stage transistors (Emitters) and is crossed
by large amount of current, this path is also used in this device to dissipate the heating generated (no
needs of external heatsinker).
Referring to the typical application circuit, the separation between the two GND paths must be ob-
tained connecting them separately (star routing) to the bulk
Electrolithic capacitor C1 (470μF).
Regarding the Power Gnd dimensioning we have to consider the Dissipated Power the Thermal Pro-
tection Threshold and the Package thermal Characteristics.
7/13
TDA7266D Dissipating Copper Area:
Dissipated Power:
The max dissipated power happens for a THD near 1% and is given by the formula:
This gives for: Vcc = 9.5V, Rl = 8Ω ,Iq = 50mA a dissipated power of Pd = 5W.
Thermal Protection:
The thermal protection threshold is placed at a junction temperature of 150°C.
Package Thermal Characteristics:
The thermal resistance Junction to Ambient obtainable with a GND copper Area of 3x3 cm and with 16 via
holes (see picture) is about 15°C/W. This means that with the above mentioned max dissipated Power (Pd=5W)
we can expect a 75°C, this gives a safety margin before the thermal protection intervention in the consumer
environments where a 50°C ambient is specified as maximum
The Thermal constraints determine the max supply voltage that can be used for the different Load Impedances,
this in order to avoid the thermal Protection Intervention.
The max. dissipated power must be not in excess of 5W , this at turns gives the following operating supply volt-
ages: Filter Capacitors Positioning:
The two Ceramic capacitors C2/C7 (100nF) must be placed as close as possible
respectively to the two Vcc pins ( 6 - 15) in order to avoid the possibiltiy of oscillations arising on the
output Audio signals.
Package Informations:You can find a complete description for the PowerSO package into the APPLICATION NOTE AN668 available
on web.
Here we want to focalize the attention only on the the Dissipating elements and ground layer.
PdmaxW() 2VCC2Rl------
-------------- IqVCC+⋅=
