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HCF4541 Programmable Timer

HCF4541 Programmable Timer
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September 2002 1/10 n 16 STAGE BINARY COUNTER n LOW SYMMETR. OUTPUT RESISTANCE, TYPICALLY 100W at VDD = 15V n OSCILLATOR FREQUENCY RANGE : DC to 100KHz n AUTO OR MASTER RESET DISABLES OSCILLATOR DURING RESET TO REDUCE POWER DISSIPATION n OPERATES WITH VERY SLOW CLOCK RISE AND FALL TIMES n BUILT-IN LOW-POWER RC OSCILLATOR n EXTERNAL CLOCK (applied to pin 3) CAN BE USED INSTEAD OF OSCILLATOR n OPERATES AS 2n FREQUENCY DIVIDER OR AS A SINGLE-TRANSITION TIMER n Q/Q SELECT PROVIDES OUTPUT LOGIC LEVEL FLEXIBILITY n CAPABLE OF DRIVING SIX LOW POWER TTL LOADS, THREE LOW POWER SCHOTTKY LOADS, OR SIX HTL LOADS OVER THE RATED TEMP. RANGE n 5V, 10V AND 15V PARAMETRIC RATINGS n 100% TESTED FOR QUIESCENT CURRENT AT 20V n MEETS ALL REQUIREMENTS OF JEDEC JESD13B " STANDARD SPECIFICATIONS FOR DESCRIPTION OF B SERIES CMOS DEVICES" DESCRIPTION The HCF4541B is a monolithic integrated circuit fabricated in Metal Oxide Semiconductor technology available in DIP and SOP packages. This device is composed of a 16-stages binary counter, an oscillator controlled by 2 external resistors and a capacitor, an output control logic and an automatic power-on reset circuit. The counter varies on positive-edge clock transition and it can be cleared by the MASTER RESET input. The output from this timer is the Q or Q output from the 8th, 13th, or 16th counter stage. The choice of the stage depends on the time HCF4541B PROGRAMMABLE TIMER PIN CONNECTION ORDER CODES PACKAGE TUBE T & R DIP HCF4541BEY SOP HCF4541BM1 HCF4541M013TR DIP SOP

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HCF4541B 2/10 select inputs A or B (see frequency selection table). The output is available in one of the two modes that can be selected via the MODE input pin 10 (see truth table). The output turns out as a continuos square wave, with a frequency equal to the oscillator frequency divided by 2N when this MODE input is a logic "1". When it is a logic "0" and after a MASTER RESET is started, and Q output has been selected, the output goes up to a high state after 2 N-1 counts. It remains in that state till another MASTER RESET pulse is apply or the mode input is a logic "1". The process...

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HCF4541B 3/10 FUNCTIONAL DIAGRAM FREQUENCY SELECTION TABLE TRUTH TABLE LOGIC DIAGRAM A B N. of Stages N Count 2N L L 13 8192 L H 10 1024 H L 8 256 H H 16 65536 PIN STATE L H 5 Auto Reset On Auto Reset Disable 6 Master Reset Off Master Reset On 9 Output Initially Low After Reset (Q) Output Initially High After Reset (Q) 10 Single Transition Mode Recycle Mode

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HCF4541B 4/10 ABSOLUTE MAXIMUM RATINGS Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these conditions is not implied. All voltage values are referred to VSS pin voltage. RECOMMENDED OPERATING CONDITIONS Symbol Parameter Value Unit VDD Supply Voltage -0.5 to +22 V VI DC Input Voltage -0.5 to VDD + 0.5 V II DC Input Current ± 10 mA PD Power Dissipation per Package 200 mW Power Dissipation per Output Transistor 100 mW Top Operating Temperature -55 to +125 °C Tstg Storage Temperature -65 to +150 °C Symbol Parameter Value Unit...

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HCF4541B 6/10 DYNAMIC ELECTRICAL CHARACTERISTICS (Tamb = 25°C, CL = 50pF, RL = 200KW, tr = tf = 20 ns) (*) Typical temperature coefficient for all VDD value is 0.3 %/°C. DIGITAL TIMER APPLICATION A positive MASTER RESET pulse clears the counter and latch. The Output goes high and keeps up till the number of pulses, selected by A and B , are counted. This circuit is retriggerable and is as accurate as the input frequency. If a more accurate circuit is desired, an external clock can be used on pin 3. A set-up time equal to the width of the one shot output is required immediately following...

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HCF4541B 7/10 TEST CIRCUIT CL = 50pF or equivalent (includes jig and probe capacitance) RL = 200KW RT = ZOUT of pulse generator (typically 50W)

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HCF4541B 10/10 Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specifications mentioned in this publication are subject to change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products are not authorized...

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