SN74LS48N BCD to 7-Segment Decoder/Driver
The 74LS48 IC features active low outputs designed for driving common – anode LEDs or incandescent indicators directly. It accepts a binary coded decimal as input and converts it into a pattern to drive a seven-segment for displaying digits 0 to 9. The 74LS48 IC has a wide range of working voltage, a wide range of working conditions, and directly interfaces with CMOS, NMOS, and TTL. The output of the IC always comes in TTL which makes it easy to work with other TTL devices and microcontrollers. The IC 74LS20 is smaller in size and it has a much faster speed which makes it reliable in every kind of device.
The SN54 /74LS48 is a BCD to 7-Segment Decoder consisting of NAND gates, input buffers and seven AND-OR-INVERT gates. Seven NAND gates and one driver are connected in pairs to make BCD data and its complement available to the seven decoding AND-OR-INVERT gates. The remaining NAND gate and three input buffers provide lamp test, blanking input/rippleblanking input for the LS48.
The circuit accepts 4-bit binary-coded-decimal (BCD) and, depending on the state of the auxiliary inputs, decodes this data to drive other components. The relative positive logic output levels, as well as conditions are required at the auxiliary inputs. The LS48 circuit incorporates automatic leading and/or trailing edge zero-blanking control (RBI and RBO). Lamp Test (LT) may be activated any time when the BI/RBO node is HIGH. Both devices contain an overriding blanking input (BI) which can be used to control the lamp intensity by varying the frequency and duty cycle of the BI input signal or to inhibit the outputs.
• Lamp Intensity Modulation Capability (BI/RBO)
• Internal Pull-Ups Eliminate Need for External Resistors
• Input Clamp Diodes Eliminate High-Speed Termination Effects
Features
Standard 74LS48 DIP IC
Accepts Four Line of BCD Input and Converts this to Seven Open Collector Outputs
Pull-Up Resistors Included
Lamp Test Input
Resources:
2. 74LS48 BCD to 7-Segment decoder Pinout and Examples