Product Info

VTech proprietary and confidential
VTech Communications LTD.
R&D Department
The document is VTech’s proprietary information, Please do not disclose to third party without VTech’s consent
Ref. No.: 20191009 Version: 01 Date: 09 Oct, 2019 Page 5 of 33
H37
I/O
PIO[18]
Programmable input/output line 18.
H38
O
LED[2]
Open-drain output
H39
I
MIC_AN
Line or microphone input negative, channel A
H40
I
MIC_AP
Line or microphone input positive, channel A
H41
I
MIC_BIAS
Microphone bias
• I: input pin
• O: Output pin
• I/O: Input/Output pin
• P: Power pin
FIGURE 1-3:External Programming Header Connections
Configuration and firmware programming modes are entered according to the system configuration I/O pins as shown in the
figure above.
2 Bluetooth modem
The Bluetooth modem includes the following components:
• RF ports
• RF receiver
• RF transmitter
• Bluetooth radio synthesizer
• Baseband
2.1 RF ports (BT-RF)
VTBM-A01 BT Module contains a balun that combines the balanced outputs of the PA on transmit and produces the
balanced input signals for the LNA required on receive.
2.2 RF receiver
The receiver features a near-zero IF architecture that enables the channel filters to be integrated onto the die. Sufficient out-
of-band blocking specification at the LNA input enables the receiver to operate close to GSM and WCDMA cellular phone
transmitters without being desensitized. A digital FSK discriminator means that no discriminator tank is needed and its