Operating Manual

Hardware Design Guidance
Power supply、ground wire
1、 Ground wire
The bluetooth ground wire are divided into AGND、PGND、and GND：
a）
AGND and GND must be strictly distinguished, connected at the battery entrance or in the front of IC
ground side; in the case of limited PCB board space, priority should be given to ensuring the connectivity of
GND and the battery ground circuit, and the route must be thick .
b） PGND and GND must be strictly distinguished,PGND go back to chip side behind of base pin and connect
GND nearby.
2、DCDC Picture 1. DC-DC switching power circuit
Like picture 1，
DC-DC switching power circuit is composed of SW 、 PGND 、BT_ AVDD、 L2、C3、C4、C9 （marked
red color）；L2/C3/C4/C9 should be as close as possible to the base pin in layout;C3/C4/C9 ground circuit must return
to the PGND pin at the shortest distance (no holes and as thick as possible), L2 + 1.5V routing must first pass the C4
(106) capacitort then go into IC (refer to picture 2)；L2 should be as far away from the easily disturbed parts (such as
RF and DAC) as possible;. Do not install any signal line under the inductor or L2 should choose winding inductor or
power laminated inductor with minimum impedance
Picture 2. Ground Circuit of DC-DC Switching Power Supply