74HCT390DB: Dual decade ripple counter
The 74HC390; 74HCT390 is a dual 4-bit decade ripple counter divided into four separately
clocked sections. The counters have two divide-by-2 sections and two divide-by-5
sections. These sections share an asynchronous master reset input (nMR) and can be used
in a BCD decade or bi-quinary configuration. If master reset inputs 1MR and 2MR are used
to clear all 8 bits of the counter simultaneously, numerous counting configurations are
possible within one package. Section clocks nCP0 and nCP1, allow ripple counter or frequency division
applications of divide-by-2, 4, 5, 10, 20, 25, 50 or 100.
The HIGH-to-LOW transition of the clock inputs nCP0 and nCP1 trigger each section. For BCD decade operation, the
nQ0 output is connected to the nCP1 input of the divide-by-5 section. For bi-quinary
decade operation, the nQ3 output is connected to the nCP0
input and nQ0 becomes the decade output. A HIGH on the nMR input overrides the clocks
and sets the four outputs LOW. Inputs include clamp diodes. It enables the use of
current limiting resistors to interface inputs to voltages in excess of
VCC.
74HCT390DB: Product Block Diagram
Outline 3d SOT338-1
Data Sheets (1)
Application Notes (2)
Users Guides (1)
| Name/Description | Modified Date |
|---|
| HC/T User Guide (REV 1.0) PDF (508.0 kB) HCT_USER_GUIDE [English] | 01 Nov 1997 |
Selector Guides (2)
Package Information (1)
Supporting Information (2)
Ordering Information
| Product | Status | Family | VCC (V) | Function | Output drive capability (mA) | Description | Package version | Logic switching levels | tpd (ns) | fmax (MHz) | Power dissipation considerations | Tamb (Cel) | Rth(j-a) (K/W) | Ψth(j-top) (K/W) | Rth(j-c) (K/W) | Package name | No of pins |
|---|
| 74HCT390DB | Active | HC(T) | 4.5 - 5.5 | BCD/decade counters | +/- 4.0 | TTL enabled | SOT338-1 | TTL | 18 | 55 | low | -40~125 | 148 | 42.0 | | SSOP16 | 16 |
Package Information
| Product ID | Package Description | Outline Version | Reflow/Wave Soldering | Packing | Product Status | Part NumberOrdering code(12NC) | Marking | Chemical Content | RoHS / Pb Free / RHF | LeadFree Conversion Date | EFR | IFR(FIT) | MTBF(hour) | MSL | MSL LF |
|---|
| 74HCT390DB | | SOT338-1 | SSOP-TSSOP-VSO-REFLOW
SSOP-TSSOP-VSO-WAVE
SSOP-TSSOP-VSO-REFLOW
SSOP-TSSOP-VSO-WAVE | Reel 13" Q1/T1 | Active | 74HCT390DB,118
(9351 899 30118) | HCT390 | 74HCT390DB |    | week 12, 2005 | 84.9 | 6.62 | 1.51E8 | 1 | 1 |
| Bulk Pack | Active | 74HCT390DB,112
(9351 899 30112) | HCT390 | 74HCT390DB | | week 12, 2005 | 84.9 | 6.62 | 1.51E8 | 1 | 1 |
