XINLUDA XD74LS48

The 74LS47 feature active-low outputs designed for driving commonanode LEDs or incandescent indicators directly. The 74LS48 feature activehigh outputs for driving lamp buffers lamp buffers or common-cathode LEDs. All of the circuits have full ripple-blanking input/output controls and a lamp test input. Segment identification and resultant displays are shown below. Display patterns for BCD input counts above 9 are unique symbols to authenticate input conditions. The 74LS47 and 74LS48 circuits incorporate automatic leading and/or trailing-edge zeroblanking control (RBI and RBO). Lamp test (LT) of these types may be performed at any time when the BI/RBO node is at a high level. All types contain an overriding blanking input (BI), which can be used to control the lamp intensity by pulsing or to inhibit the outputs. Inputs and outputs are entirely compatible for use with TTL logic outputs.

• 74LS47
  • Open-Collector Outputs Drive Indicators Directly
  • Lamp-Test Provision
  • Leading/Trailing Zero
• 74LS48
  • Internal Pull-Ups Eliminate Need for External Resistors
  • Lamp-Test Provision
  • Leading/Trailing Zero Suppression