NB-IoT Module Series
BC66&BC660K-GL Compatible Design
BC66&BC660K-GL
_
Compatible_Design 24 / 30
1. The level conversion circuit solution shown above is not suitable for applications with high baud rates
exceeding 460 kbps.
2.
“
” represents the test points of UART interfaces. It is recommended to reserve the test points of
VBAT_BB, VBAT_RF and PWRKEY for BC66, and the test points of VBAT, BOOT and RESET_N for
BC660K-GL, for convenient firmware upgrade and debugging when necessary.
3. While using BC66, mount R1 in
blue
and do not mount R2 in
green
.
4. While using BC660K-GL, do not pull up MAIN_RXD to
VDD_EXT directly, do not mount
R1 in
blue
,
and substitute D1 in
red
with a 1 k
Ω resistor.
5. While using BC660K-GL, do not mount R2 in
green
.
6. For BC660K-GL, pay attention to the following notes about VIO_SEL:
When VIO_SEL is grounded and VBAT
˂
3.3 V, VDD_EXT = VBAT;
When VIO_SEL is grounded and VBAT
≥ 3.3 V, VDD_EXT = 3.3 V;
When VIO_SEL is floating, VDD_EXT = 1.8 V.
4.9. ADC Interface
BC66 modules provide a 10-bit ADC input channel to read the voltage value of ADC0, while BC660K-GL
provides a 12-bit ADC input channel of the same use.
⚫
The maximum voltage value applicable to BC66
’s ADC0 is 1.4 V.
⚫
The maximum voltage value applicable to BC660K-GL
’s ADC0 is 1.2 V.
Table 9: ADC Interface Information
For BC660K-GL, a 320
kΩ pull-down resistor is integrated inside its BB chip, to which the ADC pin is
connected. This resistor needs to be considered when you apply the voltage division rule (voltage
divider) to relevant calculations.
Module
Pin Name
Pin No.
Description
BC66
ADC0
9
General-purpose ADC interface
BC660K-GL
ADC0
9
General-purpose ADC interface
NOTES
NOTE
