Block Diagram

U7
GPS Single chip
MTK MT3337
U6
Bluetooth MPU chip
nRF52820
ANT2
BT Antenna
GT-120B Block Diagram
X2
Crystal
32MHz
X1
Crystal
32.768K
System Clock
RTC Clock
U4
BMA253
G-Sensor
CN1
Micro USB
System Power
3.3V
UART
LED1 / LED2
DISPLAY
J1
Li-polymer
Battery
U1
EUP8054
Battery Charge
U2
RT9078-3.3V
LDO 3.3V
U3
FM25Q16
Flash Memory
ANT1
GPS Antenna
X3
OSC
26MHz
X4
Crystal
32.768K
DC5V
S1
Push Buttom
USB2.0 Full Speed
U1 / Q2
Battery
Protection