LED level meter driver, 5-point, VU scale

The BA6137 is a driver IC for LED VU level meters in stereo equipment and other display applications. The IC displays the input level (range:
10dB to +6dB) on a 5-point, bar-type LED display.

Features
1) Rectifier amplifier allows either AC or DC input.
2) Constant-current outputs for constant LED current when the power supply voltage fluctuates.
3) Current output is optimized for red LEDs, for low power dissipation.
4) Built-in reference voltage means that power supply voltage fluctuations do not effect the display.
5) Wide operating power supply voltage range (3.5V to 16V) for a wide range of applications.
6) Low PCB space requirements. Comes in a compact 9-pin SIP package and requires few attached components.

Applications
VU meters, signal meters, and other display devices.