MC54HC139A Motorola, MC54HC139A Datasheet - Page 4

• Manufacturer Part Number: MC54HC139A
• Description: Dual 1-of-4 Decoder/Demultiplexer
• Manufacturer: Motorola

MOTOROLA
ADDRESS INPUTS
A0 a , A1 a , A0 b , A1 b (Pins 2, 3, 14, 13)
decoder is enabled, determine which of its four active–low
outputs is selected.
CONTROL INPUTS
Select a , Select b (Pins 1, 15)
MC54/74HC139A
Address inputs. These inputs, when the respective 1–of–4
Active–low select inputs. For a low level on this input, the
SELECT
A0
A1
EXPANDED LOGIC DIAGRAM
PIN DESCRIPTIONS
(1/2 OF DEVICE)
4
outputs for that particular decoder follow the Address inputs.
A high level on this input forces all outputs to a high level.
OUTPUTS
Y0 a – Y3 a , Y0 b – Y3 b (Pins 4 – 7, 12, 11, 10, 9)
when addressed and the appropriate Select input is active.
These outputs remain high when not addressed or the ap-
propriate Select input is inactive.
Active–low outputs. These outputs assume a low level
High–Speed CMOS Logic Data
DL129 — Rev 6
Y0
Y1
Y2
Y3