Programmable timer
February 1988
CD4541BM CD4541BC Programmable Timer
General Description
The CD4541B Programmable Timer is designed with a 16-stage binary counter an integrated oscillator for use with an external capacitor and two resistors output control logic and a special power-on reset circuit The special features of the power-on reset circuit are first noadditional static power consumption and second the part functions across the full voltage range (3V–15V) whether power-on reset is enabled or disabled Timing and the counter are initialized by turning on power if the power-on reset is enabled When the power is already on an external reset pulse will also initialize the timing and counter After either reset is accomplished the oscillator frequency isdetermined by the external RC network The 16-stage counter divides the oscillator frequency by any of 4 digitally controlled division ratios
Y Y
Y
Y
Y
Y Y
Y
Y Y Y
Features
Y Y Y
Y Y
Available division ratios 28 210 213 or 216 Increments on positive edge clock transitions Built-in low power RC oscillator ( g 2% accuracy over temperature range and g 10% supply and g 3% over k10 kHz) processing
Y
Oscillator frequency range DC to 100 kHz Oscillator may be bypassed if external clock is available (apply external clock to pin 3) Automatic reset initializes all counters when power turns on External master reset totally independent of automatic reset operation Operates at 2n frequency divider or single transition timer Q Q select provides output logic level flexibilityReset (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 Wide supply voltage range 3 0V to 15V High noise immunity 0 45 VDD (typ ) 5V – 10V – 15V parameter ratings Symmetrical output characteristics Maximum input leakage 1 mA at 15V over full temperature range Highoutput drive (pin 8) min one TTL load
Logic Diagram
VDD e Pin 14 VSS e Pin 7
TL F 6001 – 1
Connection Diagram
Dual-In-Line Package Order Number CD4541B
NC
Not connected
Top View
C1995 National Semiconductor Corporation TL F 6001
TL F 6001 – 2
RRD-B30M105 Printed in U S A
Absolute Maximum Ratings (Notes 1
2)
If Military Aerospace specified devices are required pleasecontact the National Semiconductor Sales Office Distributors for availability and specifications
b 0 5V to a 18V Supply Voltage (VDD) b 0 5V to VDD a 0 5V Input Voltage (VIN) b 65 C to a 150 C Storage Temperature Range (TS) Power Dissipation (PD) Dual-In-Line 700 mW Small Outline 500 mW Lead Temperature (TL) (soldering 10 sec ) 260 C
Recommended Operating Conditions (Note 2)
Supply Voltage(VDD) Input Voltage (VIN) Operating Temperature Range CD4541BM CD4541BC 3V to 15V 0 to VDD
b 55 C to a 125 C b 40 C to a 85 C
DC Electrical Characteristics (Note 2)
Symbol IDD Parameter Conditions
CD4541BM
b 55 C a 25 C a 125 C
Units mA mA mA V V V V V V
Min Quiescent Device Current VDD e 5V VIN e VDD or VSS VDD e 10V VIN e VDD or VSS VDD e 15V VIN e VDD or VSS Low Level OutputVoltage VDD e 5V VDD e 10V VDD e 15V High Level Output Voltage VDD e 5V VDD e 10V VDD e 15V Low Level Input Voltage
Max 5 10 20 0 05 0 05 0 05
Min
Typ 0 005 0 010 0 015 0 0 0
Max 5 10 20 0 05 0 05 0 05
Min
Max 150 300 600 0 05 0 05 0 05
VOL
lIOl k 1 mA lIOl k 1 mA
4 95 9 95 14 95
VOH
4 95 9 95 14 95 15 30 40
5 10 15 2 4 6 15 30 40
4 95 9 95 14 95 15 30 40 35 70 11 016 28 10 9 4 49 2 37 9 24
b1 0
VIL
VDD e 5V VO e 0 5V or 4 5V VDD e 10V VO e 1 0V or 9 0V VDD e 15V VO e 1 5V or 13 5V VDD e 5V VO e 0 5V or 4 5V VDD e 10V VO e 1 0V or 9 0V VDD e 15V VO e 1 5V or 13 5V VDD e 5V VO e 0 4V VDD e 10V VO e 0 5V VDD e 15V VO e 1 5V 35 70 11 0 2 85 4 96 19 3 7 96 4 19 16 3
V V V V V V mA mA mA mA mA mA
VIH
High Level Input Voltage
35 70 11 0 2 27...
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