1. General description
The HEF4543B is a BCD to 7-segment latch/decoder/driver for liquid crystal and LED displays.
It has four address inputs (D0 to D3), an active LOW latch enable input (LE), an active HIGH
blanking input (BL), an active HIGH phase input (PH) and seven buffered segment outputs (Qa to
Qg).
The circuit provides the function of a 4-bit storage latch and an 8-4-2-1 BCD to 7-segment
decoder/driver. It can invert the logic levels of the output combination. The phase (PH), blanking
(BL) and latch enable (LE) inputs are used to reverse the function table phase, blank the display
and store a BCD code, respectively.
For liquid crystal displays, a square-wave is applied to PH and the electrical common back-plane of
the display. The outputs of the device are directly connected to the segments of the liquid crystal.
It operates over a recommended VDD power supply range of 3 V to 15 V referenced to VSS (usually
ground). Unused inputs must be connected to VDD, VSS, or another input.
2. Features and benefits
• Wide supply voltage range from 3.0 V to 15.0 V
• CMOS low power dissipation
• High noise immunity
• Fully static operation
• 5 V, 10 V, and 15 V parametric ratings
• Standardized symmetrical output characteristics
• Complies with JEDEC standard JESD 13-B
• ESD protection:
• HBM JESD22-A114F exceeds 2000 V
• MM JESD22-A115-B exceeds 200 V
• Specified from -40 °C to +85 °C