Document
DM5490 DM7490A DM7493A Decade and Binary Counters
July 1992
DM5490 DM7490A DM7493A Decade and Binary Counters
General Description
Each of these monolithic counters contains four masterslave flip-flops and additional gating to provide a divide-bytwo counter and a three-stage binary counter for which the count cycle length is divide-by-five for the 90A and divideby-eight for the 93A All of these counters have a gated zero reset and the 90A also has gated set-to-nine inputs for use in BCD nine’s complement applications To use their maximum count length (decade or four-bit binary) the B input is connected to the QA output The input count pulses are applied to input A and the outputs are as described in the appropriate truth table A symmetrical divide-by-ten count can be obtained from the 90A counters by connecting the QD output to the A input and applying the input count to the B input which gives a divide-by-ten square wave at output QA
Features
Y
Y
Typical power dissipation 90A 145 mW 93A 130 mW Count frequency 42 MHz
Connection Diagrams
Dual-In-Line Package
TL F 6533 – 1
Order Number DM5490J DM5490W or DM7490AN See NS Package Number J14A N14A or W14B Dual-In-Line Package
TL F 6533 – 2
Order Number DM7493AN See NS Package Number N14A
C1995 National Semiconductor Corporation
TL F 6533
RRD-B30M105 Printed in U S A
Absolute Maximum Ratings (Note)
If Military Aerospace specified devices are required please contact the National Semiconductor Sales Office Distributors for availability and specifications Supply Voltage 7V Input Voltage 5 5V Operating Free Air Temperature Range b 55 C to a 125 C DM54 DM74 0 C to a 70 C Storage Temperature Range
b 65 C to a 150 C
Note The ‘‘Absolute Maximum Ratings’’ are those values beyond which the safety of the device cannot be guaranteed The device should not be operated at these limits The parametric values defined in the ‘‘Electrical Characteristics’’ table are not guaranteed at the absolute maximum ratings The ‘‘Recommended Operating Conditions’’ table will define the conditions for actual device operation
Recommended Operating Conditions
Symbol VCC VIH VIL IOH IOL fCLK tW Supply Voltage High Level Input Voltage Low Level Input Voltage High Level Output Current Low Level Output Current Clock Frequency (Note 5) Pulse Width (Note 5) A B A B Reset tREL TA Reset Release Time (Note 5) Free Air Operating Temperature 0 0 15 30 15 25
b 55
Parameter Min 45 2
DM5490 Nom 5 Max 55 08
b0 8
DM7490A Min 4 75 2 08
b0 8
Units Max 5 25 V V V mA mA MHz
Nom 5
16 32 16 0 0 15 30 15 25 125 0
16 32 16
ns ns 70 C
’90A Electrical Characteristics
over recommended operating free air temperature range (unless otherwise noted) Symbol VI VOH VOL II IIH Parameter Input Clamp Voltage High Level Output Voltage Low Level Output Voltage Input Current Input Voltage Max Conditions VCC e Min II e b12 mA VCC e Min IOH e Max VIL e Max VIH e Min VCC e Min IOL e Max VIH e Min VIL e Max (Note 4) VCC e Max VI e 5 5V VCC e Max VI e 2 7V A Reset B IIL Low Level Input Current VCC e Max VI e 0 4V A Reset B IOS ICC Short Circuit Output Current Supply Current VCC e Max (Note 2) VCC e Max (Note 3) DM54 DM74
b 20 b 18
Min
Typ (Note 1)
Max
b1 5
Units V V
24
34 02 04 1 80 40 120
b3 2 b1 6 b4 8 b 57 b 57
V mA
High Level Input Current
mA
mA
mA mA
29
42
Note 1 All typicals are at VCC e 5V TA e 25 C Note 2 Not more than one output should be shorted at a time Note 3 ICC is measured with all outputs open both RO inputs grounded following momentary connection to 4 5V and all other inputs grounded Note 4 QA outputs are tested at IOL e Max plus the limit value of IIL for the B input This permits driving the B input while maintaining full fan-out capability Note 5 TA e 25 C and VCC e 5V
2
’90A Switching Characteristics
at VCC e 5V and TA e 25 C (See Section 1 for Test Waveforms and Output Load) Symbol Parameter From (Input) To (Output) Min fMAX tPLH tPHL tPLH tPHL tPLH tPHL tPLH tPHL tPLH tPHL tPLH tPHL tPHL Maximum Clock Frequency Propagation Delay Time Low to High Level Output Propagation Delay Time High to Low Level Output Propagation Delay Time Low to High Level Output Propagation Delay Time High to Low Level Output Propagation Delay Time Low to High Level Output Propagation Delay Time High to Low Level Output Propagation Delay Time Low to High Level Output Propagation Delay Time High to Low Level Output Propagation Delay Time Low to High Level Output Propagation Delay Time High to Low Level Output Propagation Delay Time Low to High Level Output Propagation Delay Time High to Low Level Output Propagation Delay Time High to Low Level Output A to QA B to QB A to QA A to QA A to QD A to QD B to QB B to QB B to QC B to QC B to QD B to QD SET-9 to QA QD SET-9 to QB QC SET-0 Any Q 32 16 16 18 48 50 16 21 32 35 32 35 30 40 40 ns ns ns ns ns ns ns ns ns ns ns ns ns RL e 400X CL e 15 pF Max MHz Units
3
Recommended Operating Conditions
Symbol VCC VIH VIL IOH IOL fCLK tW Supply Voltage High Level Input Vo.