LG GB110, Service Manual

Page: 23 / 142

23
3.5 Audio Amplifier (TPA6205A1)
Figure.3-5 TPA6205A1 FUNCTIONAL BLOCK DIAGRAM
FEATURES
· 1.25 W Into 8W From a 5-V Supply at THD = 1% (Typical)
· Compatible with Low Power (1.8V Logic) I/O
· Shutdown Pin has 1.8V Compatible Threshold
· Low Supply Current: 1.7mA Typical
· Shutdown Current < 10mA
· Only Five External Components
–
Improved PSRR (90 dB) and Wide Supply Voltage (2.5V to 5.5V) for Direct Battery Operation
– Fully Differential Design Reduces RF Rectification
–
Improved CMRR Eliminates Two Input Coupling Capacitors
–
C(
BYPASS
) Is Optional Due to Fully Differential Design and High PSRR
· Available in 3 mm x 3 mm QFN Package(DRB)
· Available in an 8-Pin PowerPAD™ MSOP(DGN)
· Avaliable in a 2 mm x 2 mm MicroStar Junior™ BGA Package (ZQV
)
APPLICATIONS
· Designed for Wireless Handsets, PDAs, and other mobile devices
· Compatible with Low Power (1.8V Logic) I/O Threshold control signals
DESCRIPTION
The TPA6205A1 is a 1.25-W mono fully differential amplifier designed to drive a speaker with at
least 8-W impedance while consuming less than 37 mm2 (ZQV package option) total printed-circuit
board (PCB) area in most applications. This device operates from 2.5 V to 5.5 V, drawing only 1.7
mA of quiescent supply current. The TPA6205A1 is available in the space-saving 2 mm x 2 mm
MicroStar Junior™ BGA package, and the space saving 3 mm x 3 mm QFN (DRB) package.
Features like 85-dB PSRR from 90 Hz to 5 kHz, improved RF-rectification immunity, and small
PCB area makes the TPA6205A1 ideal for wireless handsets. A fast start-up time of 4 ms with
minimal pop makes the TPA6205A1 ideal for PDA applications.