- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄382821 > 74C925 (Fairchild Semiconductor Corporation) 4-Digit Counters with Multiplexed PDF資料下載
參數(shù)資料
| 型號： | 74C925 |
| 廠商： | Fairchild Semiconductor Corporation |
| 元件分類： | 通用總線功能 |
| 英文描述： | 4-Digit Counters with Multiplexed |
| 中文描述： | 4位計數(shù)器的復(fù)用 |
| 文件頁數(shù)： | 1/9頁 |
| 文件大小： | 97K |
| 代理商： | 74C925 |
October 1987
Revised January 1999
M
1999 Fairchild Semiconductor Corporation
DS005919.prf
www.fairchildsemi.com
MM74C925 MM74C926 MM74C927 MM74C928
4-Digit Counters with Multiplexed
7-Segment Output Drivers
General Description
The MM74C925, MM74C926, MM74C927 and MM74C928
CMOS counters consist of a 4-digit counter, an internal out-
put latch, NPN output sourcing drivers for a 7-segment dis-
play, and an internal multiplexing circuitry with four
multiplexing outputs. The multiplexing circuit has its own
free-running oscillator, and requires no external clock. The
counters advance on negative edge of clock. A HIGH sig-
nal on the Reset input will reset the counter to zero, and
reset the carry-out LOW. A LOW signal on the Latch
Enable input will latch the number in the counters into the
internal output latches. A HIGH signal on Display Select
input will select the number in the counter to be displayed;
a LOW level signal on the Display Select will select the
number in the output latch to be displayed.
The MM74C925 is a 4-decade counter and has Latch
Enable, Clock and Reset inputs.
The MM74C926 is like the MM74C925 except that it has a
display select and a carry-out used for cascading counters.
The carry-out signal goes HIGH at 6000, goes back LOW
at 0000.
The MM74C927 is like the MM74C926 except the second
most significant digit divides by 6 rather than 10. Thus, if
the clock input frequency is 10 Hz, the display would read
tenths of seconds and minutes (i.e., 9:59.9).
The MM74C928 is like the MM74C926 except the most sig-
nificant digit divides by 2 rather than 10 and the carry-out is
an overflow indicator which is HIGH at 2000, and it goes
back LOW only when the counter is reset. Thus, this is a
3-digit counter.
Features
I
Wide supply voltage range:
I
Guaranteed noise margin:
I
High noise immunity:
3V to 6V
1V
0.45 V
CC
(typ.)
I
High segment sourcing current:
@ V
CC
1.6V, V
CC
=
5V
I
Internal multiplexing circuitry
40 mA
Design Considerations
Segment resistors are desirable to minimize power dissipa-
tion and chip heating. The DS75492 serves as a good digit
driver when it is desired to drive bright displays. When
using this driver with a 5V supply at room temperature, the
display can be driven without segment resistors to full illu-
mination. The user must use caution in this mode however,
to prevent overheating of the device by using too high a
supply voltage or by operating at high ambient tempera-
tures.
The input protection circuitry consists of a series resistor,
and a diode to ground. Thus input signals exceeding V
CC
will not be clamped. This input signal should not be allowed
to exceed 15V.
Ordering Code:
Order Number
MM74C925N
MM74C926N
MM74C927N
MM74C928N
Package Number
N16E
N18A
N18A
N18A
Package Description
16-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300” Wide
18-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300” Wide
18-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300” Wide
18-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300” Wide
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| 74C926 | 4-Digit Counters with Multiplexed |
| 74F1056 | 8-Bit Schottky Barrier Diode Array |
| 74F1056SC | 8-Bit Schottky Barrier Diode Array |
| 74F1056SCX | COMMON ANODE DIODE ARRAY|SO |
| 74F1071 | 18-Bit Undershoot/Overshoot Clamp |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| 74C925 WAF | 制造商:Fairchild Semiconductor Corporation 功能描述: |
| 74C926 | 制造商:FAIRCHILD 制造商全稱:Fairchild Semiconductor 功能描述:4-Digit Counters with Multiplexed |
| 74C927 WAF | 制造商:Fairchild Semiconductor Corporation 功能描述: |
| 74C928 WAF | 制造商:Fairchild Semiconductor Corporation 功能描述: |
| 74C93 WAF | 制造商:Fairchild Semiconductor Corporation 功能描述: |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。