■ Function Description

1. Working voltage: 1.35V – 5.00VDC

2. Sound: Down Bi Bi Sudden sound

3. BZ1, BZ2: inverted click output : a. BZ1 -- duty = 1/3 : b. BZ2 -- duty = 1/6

4. KEY : LEVEL HOLD mode, connected to VDD

5. Rosc : External resistance adjustment speed

6. LAMP: positive output - connected to NPN 8050 transistor, lit with Bi Bi

7. LED: Negative output - Connect to NPN 8050 transistor, light off with Bi Bi