Tripath Technology, Inc. - Technical Information
E X T E R N A L C O M P O N E N T S D E S C R I P T I O N (Refer to the Application/Test Circuit)
Components Description
RI
Inverting Input Resistance to provide AC gain in conjunction with RF. This input is
biased at the BIASCAP voltage (approximately 2.4VDC).
RF
Feedback resistor to set AC gain in conjunction with RI;
. Please refer
AV = 12(RF / RI)
to the Amplifier Gain paragraph in the Application Information section.
CI
AC input coupling capacitor which, in conjunction with RI, forms a highpass filter at
fC = 1 (2πRICI)
RREF
CA
Bias resistor. Locate close to pin 6 (REF) and ground at pin 8 (AGND2).
BIASCAP decoupling capacitor. Should be located close to pin 16.
Charge pump input capacitor. This capacitor should be connected directly between
pins 2 (DCAP2) and 3 (DCAP1) and located physically close to the TA2024B.
Charge pump output capacitor that enables efficient high side gate drive for the
internal H-bridges. To maximize performance, this capacitor should be connected
directly between pin 36 (CPUMP) and pin 33 (VDDA). Please observe the polarity
shown in the Application/ Test Circuit.
CD
CP
CS
Supply decoupling for the low current power supply pins. For optimum performance,
these components should be located close to the pin and returned to their
respective ground as shown in the Application/Test Circuit.
CSW
Supply decoupling for the high current, high frequency H-Bridge supply pins. These
components must be located as close to the device as possible to minimize supply
overshoot and maximize device reliability. Both the high frequency bypassing
(0.1uF) and bulk capacitor (180uF) should have good high frequency performance
including low ESR and low ESL. Panasonic HFQ or FC capacitors are ideal for the
bulk capacitor.
CZ
RZ
Zobel Capacitor.
Zobel resistor, which in conjunction with CZ, terminates the output filter at high
frequencies. The combination of RZ and CZ minimizes peaking of the output filter
under both no load conditions or with real world loads, including loudspeakers which
usually exhibit a rising impedance with frequency.
DO
LO
Schottky diodes that minimize undershoots of the outputs with respect to power
ground during switching transitions. For maximum effectiveness, these diodes must
be located close to the output pins and returned to their respective PGND. Please
see Application/Test Circuit for ground return pin.
Output inductor, which in conjunction with CO and CDO, demodulates (filters) the
switching waveform into an audio signal. Forms a second order filter with a cutoff
frequency of
and a quality factor of
)
fC = 1 (2π L O CTOT
where CTOT = CO || 2 * CDO.
Q = RL CTOT 2 L O CTOT
CO
Output capacitor.
CDO
Differential Output Capacitor. Differential noise decoupling for reduction of
conducted emissions. Must be located near chassis exit point for maximum
effectiveness.
6
TA2024B –KL/1.2/01.06
TRIPATH [ TRIPATH TECHNOLOGY INC. ]
