The MC14521B consists of a chain of 24 flip–flops with an input
circuit that allows three modes of operation. The input will function as
a crystal oscillator, an RC oscillator, or as an input buffer for an
external oscillator. Each flip–flop divides the frequency of the
24
previous flip–flop by two, consequently this part will count up to 2
=
http://onsemi.com
16,777,216. The count advances on the negative going edge of the
clock. The outputs of the last seven–stages are available for added
flexibility.
MARKING
DIAGRAMS
16
• All Stages are Resettable
• Reset Disables the RC Oscillator for Low Standby Power Drain
PDIP–16
P SUFFIX
CASE 648
MC14521BCP
AWLYYWW
• RC and Crystal Oscillator Outputs Are Capable of Driving External
Loads
1
• Test Mode to Reduce Test Time
16
• V ′ and V ′ Pins Brought Out on Crystal Oscillator Inverter to
DD
SS
SOIC–16
D SUFFIX
CASE 751B
Allow the Connection of External Resistors for Low–Power
Operation
14521B
AWLYWW
• Supply Voltage Range = 3.0 Vdc to 18 Vdc
1
• Capable of Driving Two Low–power TTL Loads or One Low–power
16
Schottky TTL Load over the Rated Temperature Range.
SOEIAJ–16
F SUFFIX
CASE 966
MC14521B
AWLYWW
1
MAXIMUM RATINGS (Voltages Referenced to V ) (Note 2.)
SS
A
= Assembly Location
Symbol
Parameter
Value
Unit
V
WL or L = Wafer Lot
YY or Y = Year
V
DD
DC Supply Voltage Range
–0.5 to +18.0
WW or W = Work Week
V , V
in out
Input or Output Voltage Range
(DC or Transient)
–0.5 to V + 0.5
V
DD
I , I
in out
Input or Output Current
(DC or Transient) per Pin
±10
mA
ORDERING INFORMATION
Device
Package
PDIP–16
SOIC–16
Shipping
P
Power Dissipation,
per Package (Note 3.)
500
mW
D
MC14521BCP
MC14521BD
2000/Box
48/Rail
T
A
Ambient Temperature Range
Storage Temperature Range
–55 to +125
–65 to +150
260
°C
°C
°C
T
stg
MC14521BDR2
SOIC–16 2500/Tape & Reel
T
Lead Temperature
L
MC14521BF
SOEIAJ–16
SOEIAJ–16
SOEIAJ–16
See Note 1.
See Note 1.
See Note 1.
(8–Second Soldering)
2. Maximum Ratings are those values beyond which damage to the device
may occur.
3. Temperature Derating:
MC14521BFEL
MC14521BFR2
Plastic “P and D/DW” Packages: – 7.0 mW/ C From 65 C To 125 C
1. For ordering information on the EIAJ version of
the SOIC packages, please contact your local
ON Semiconductor representative.
This device contains protection circuitry to guard against damage due to high
static voltages or electric fields. However, precautions must be taken to avoid
applications of any voltage higher than maximum rated voltages to this
high–impedancecircuit. For proper operation, V and V should be constrained
in
out
to the range V
(V or V
)
V
DD
.
SS
in
out
Unused inputs must always be tied to an appropriate logic voltage level (e.g.,
either V or V ). Unused outputs must be left open.
SS
DD
Semiconductor Components Industries, LLC, 2000
1
Publication Order Number:
March, 2000 – Rev. 3
MC14521B/D