Datasheet

MOTOROLA CMOS LOGIC DATA
1
MC14541B
The MC14541B programmable timer consists of a 16–stage binary
counter, an integrated oscillator for use with an external capacitor and two
resistors, an automatic power–on reset circuit, and output control logic.
Timing is initialized by turning on power, whereupon the power–on reset is
enabled and initializes the counter, within the specified V
DD
range. With the
power already on, an external reset pulse can be applied. Upon release of
the initial reset command, the oscillator will oscillate with a frequency
determined by the external RC network. The 16–stage counter divides the
oscillator frequency (f
osc
) with the n
th
stage frequency being f
osc
/2
n
.
• Available Outputs 2
8
, 2
10
, 2
13
or 2
16
• Increments on Positive Edge Clock Transitions
• Built–in Low Power RC Oscillator (± 2% accuracy over temperature
range and ± 20% supply and ± 3% over processing at < 10 kHz)
• Oscillator May Be Bypassed if External Clock Is Available (Apply
external clock to Pin 3)
• External Master Reset Totally Independent of Automatic Reset
Operation
• Operates as 2
n
Frequency Divider or Single Transition Timer
• Q/Q
Select Provides Output Logic Level Flexibility
• Reset (auto or master) Disables Oscillator During Resetting to Provide
No Active Power Dissipation
• Clock Conditioning Circuit Permits Operation with Very Slow Clock Rise
and Fall Times
• Automatic Reset Initializes All Counters On Power Up
• Supply Voltage Range = 3.0 Vdc to 18 Vdc with Auto Reset
Disabled (Pin 5 = V
DD
)
= 8.5 Vdc to 18 Vdc with Auto Reset
Enabled (Pin 5 = V
SS
)
MAXIMUM RATINGS* (Voltages Referenced to V
SS
)
Symbol Parameter Value Unit
V
DD
DC Supply Voltage – 0.5 to + 18.0 V
V
in
, V
out
Input or Output Voltage (DC or Transient) – 0.5 to V
DD
+ 0.5 V
I
in
Input Current (DC or Transient), per Pin ± 10 mA
I
out
Output Current (DC or Transient), per Pin ± 45 mA
P
D
Power Dissipation, per Package† 500 mW
T
stg
Storage Temperature – 65 to + 150
C
T
L
Lead Temperature (8–Second Soldering) 260
C
* Maximum Ratings are those values beyond which damage to the device may occur.
†Temperature Derating:
Plastic “P and D/DW” Packages: – 7.0 mW/ C From 65 C To 125 C
Ceramic “L” Packages: – 12 mW/ C From 100 C To 125 C
SEMICONDUCTOR TECHNICAL DATA
 Motorola, Inc. 1995
REV 3
1/94
L SUFFIX
CERAMIC
CASE 620
ORDERING INFORMATION
MC14XXXBCP Plastic
MC14XXXBCL Ceramic
MC14XXXBD SOIC
T
A
= – 55° to 125°C for all packages.
P SUFFIX
PLASTIC
CASE 648
D SUFFIX
SOIC
CASE 751B
PIN ASSIGNMENT
NC = NO CONNECTION
11
12
13
14
8
9
105
4
3
2
1
7
6
MODE
NC
A
B
V
DD
Q
Q/Q
SEL
NC
R
S
C
tc
R
tc
V
SS
MR
AR