JTDBT909DB

The BT909DB adopts an ASIC design, eliminating the system hang-up issues common in MCU-based solutions and preventing chip reset failures caused by under-voltage conditions. It integrates a microphone sensor detection module with built-in anti-interference processing for direct microphone input, preventing false triggering. The chip integrates an internal MOSFET discharge switch; the maximum current through the atomizer coil can exceed 6A during vaping, and with adequate PCB thermal dissipation, it supports heating wire impedances as low as 0.8Ω. The chip operates with high stability and features heating wire short-circuit protection, with output cutoff when load resistance falls below 0.4Ω (Typ.). In power-saving mode, the quiescent current is only 2.2μA (Typ.). The chip integrates an independent lithium battery charge management module, supporting various AC-DC and USB charging input sources with multi-mode charging (trickle, constant current, constant voltage) for superior charging performance. The BT909DB provides multiple protection functions: extended puffing protection, output short-circuit protection, over-temperature protection, under-voltage protection, and more. The chip also features visual LED status indication, with distinguishable LED indicators for different operating states. The BT909DB is a highly integrated, high-performance control IC for e-cigarette applications. Unlike MCU-based solutions, its ASIC design eliminates system hang-ups and chip reset failures due to under-voltage conditions. The IC integrates a microphone sensor detection module, discharge control module, and lithium battery charging module. Minimal external components are required — only 1 LED and 1 capacitor — resulting in low overall system cost.

Applications

• E-cigarette

Key features

• Simple peripheral circuit, no external MOS required
• Standby current as low as 2.2uA (Typ.) in power-saving mode
• Supports heating coil impedance as low as 0.8Ω
• 10-second long puff protection
• 3.60V (Typ.) average voltage output
• Load insertion/removal LED indication
• Independent standard three-stage (trickle - constant current - constant voltage) Li-ion battery charge management
• Preset 4.15V (Typ.) charge cutoff voltage
• Maximum charge current 520mA (Typ.); intelligent thermal control technology reduces charge current as temperature rises to deliver maximum charge current without triggering over-temperature protection; built-in short-circuit protection (SCP)
• Time-multiplexed simultaneous charge/discharge function (if puffing during charging, charging is suspended and switched to puffing mode; automatically resumes charging after puffing stops)
• Built-in under-voltage lockout (UVLO)
• Built-in over-temperature protection (OTP)
• Multiple LED display modes: simulates actual smoking process; indicates chip startup, voltage detection, various protections, and charging status
• Package: DFN2*3-8