Document
Standard ICs
BCD-to-decimal decoder
BU4028B
The BU4028B is a decoder which converts BCD signals to decimal signals. Of the ten outputs Q0 to Q9, those corresponding to the A to D input codes are set to “H”, and the others are all set to “L”. If inputs A to C are used and input D is used as disabled input, the BU4028B can also be used as a 1-of-8 decoder. Features • 1) Low power dissipation. 2) Wide range of operating power supply voltages. 3) High input impedance.
4) High fan-out. 5) Direct drive of 2 L-TTL inputs and 1LS-TTL input.
•Block diagram
Q4 1 16 VDD 15 Q3 Q4 Q2 Q0 3 Q0 Q7 4 Q7 Q9 Q5 Q5 Q6 6 Q6 Q8 7 10 A 9 Q8 Q1 B C D A 11 D 13 B Q3 14 Q1 Q2 2
•Logic circuit diagram
Q0 Q1 A B Q4 Q5 C Q6 Q7 IN D Q8 Q9 Q2 Q3
Q9
5
12 C
VSS
8
1
Standard ICs
BA4028B
•Truth table
INPUT D L L L L L L L L H H H H H H H H C L L L L H H H H L L L L H H H H B L L H H L L H H L L H H L L H H A L H L H L H L H L H L H L H L H Q9 L L L L L L L L L H L L L L L L Q8 L L L L L L L L H L L L L L L L Q7 L L L L L L L H L L L L L L L L Q6 L L L L L L H L L L L L L L L L OUTPUT Q5 L L L L L H L L L L L L L L L L Q4 L L L L H L L L L L L L L L L L Q3 L L L H L L L L L L L L L L L L Q2 L L H L L L L L L L L L L L L L Q1 L H L L L L L L L L L L L L L L Q0 H L L L L L L L L L L L L L L L
•Absolute maximum ratings (Ta = 25°C, V
Parameter Power supply voltage Power dissipation Operating temperature Storage temperature Input voltage Symbol VDD Pd Topr Tstg VIN
SS
= 0V)
Limits – 0.3 ~ + 18 1000 (DIP) – 40 ~ + 85 – 55 ~ + 150 – 0.3 ~ VDD + 0.3 Unit V mW °C °C V
2
Standard ICs
Electrical characteristics • DC characteristics (unless otherwise noted, Ta = 25°C, V
Parameter Symbol Min. 3.5 Input high level voltage VIH 7.0 11.0 — Input low level voltage VIL — — Input high level current Input low level current IIH IIL — — 4.95 Output high level voltage VOH 9.95 14.95 — Output low level voltage VOL — — – 0.16 Output high level current IOH – 0.4 – 1.2 0.44 Output low level current IOL 1.1 3.0 — Static current dissipation IDD — — Typ. — — — — — — — — — — — — — — — — — — — — — — —
BA4028B
SS
= 0V)
Unit Conditions Measurement circuit
Max. — — — 1.5 3.0 4.0 0.3 – 0.3 — — — 0.05 0.05 0.05 — — — — — — 1 2 4
VDD (V) 5
V
10 15 5
—
Fig.1
V µA µA
10 15 15 15 5
—
Fig.1
VIH = 15V VIL = 0V
Fig.1 Fig.1
V
10 15 5
IO = 0mA
Fig.1
V
10 15 5
IO = 0mA
Fig.1
VOH = 4.6V VOH = 9.5V VOH = 13.5V VOL = 0.4V VOL = 0.5V VOL = 1.5V FIg.1 Fig.1
mA
10 15 5
mA
10 15 5
µA
10 15
VI = VDD or GND
—
3
Standard ICs
Switching characteristics (Ta = 25°C, CL = 50pF, VSS = 0V)
Parameter Symbol Min. — Output rise time tTLH — — — Output fall time tTHL — — — “L” to “H” propagation delay time tPLH — — — “H” to “L” propagation delay time tPHL — — Input capacitance CIN — Typ. 180 90 65 100 50 40 300 130 90 300 130 90 5 Max. — — — — — — — — — — — — — pF ns ns ns ns Unit Conditions
BA4028B
VDD (V) 5 10 15 5 10 15 5 10 15 5 10 15 —
Measurement circuit
—
Fig.2, 3
—
Fig.2, 3
—
Fig.2,.