M74HC390B1R STMicroelectronics, M74HC390B1R Datasheet - Page 5

• Manufacturer Part Number: M74HC390B1R
• Description: IC DECADE COUNTER DUAL 16-DIP
• Manufacturer: STMicroelectronics
• Series: 74HCr

Specifications of M74HC390B1R

• Logic Type: Counter, Decade
• Direction: Up
• Number Of Elements: 2
• Number Of Bits Per Element: 4
• Reset: Asynchronous
• Timing: Synchronous
• Count Rate: 79MHz
• Trigger Type: Negative Edge
• Voltage - Supply: 2 V ~ 6 V
• Operating Temperature: -55°C ~ 125°C
• Mounting Type: Through Hole
• Package / Case: 16-DIP (0.300", 7.62mm)
• Counter Type: Decade
• Counting Sequence: Up
• Number Of Circuits: 2
• Logic Family: 74HC
• Propagation Delay Time: 280 ns, 56 ns, 48 ns
• Supply Voltage (max): 6 V
• Maximum Operating Temperature: + 125 C
• Minimum Operating Temperature: - 55 C
• Function: Dual Decade Counter
• Mounting Style: Through Hole
• Operating Supply Voltage: 2.5 V, 3.3 V, 5 V
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 497-7370-5; M74HC390B1R

M74HC390
3
Truth table
Table 2. Truth table
1. Output QA is connected to input CLOCK B for BCD count.
2. Output QD is connected to input CLOCK A for bi-quinary count.
Table 3. Truth table
CLOCK A
COUNT
X
X
0
1
2
3
4
5
6
7
8
9
QD
H
H
L
L
L
L
L
L
L
L
CLOCK B
Inputs
X
X
BCD COUNT
QC
H
H
H
H
L
L
L
L
L
L
QB
H
H
H
H
L
L
L
L
L
L
CLEAR
(1)
H
L
L
QA
H
H
H
H
H
L
L
L
L
L
Outputs
QA
QA
L
H
H
H
H
H
L
L
L
L
L
QUINARY COUNT UP
BINARY COUNT UP
BI-QUINARY
QB
QD
L
H
H
H
L
L
L
L
L
L
L
Outputs
QC
QC
L
H
H
H
H
L
L
L
L
L
L
(2)
Truth table
QD
QB
H
H
H
H
L
L
L
L
L
L
L
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