MC14521BFELG

Counter Dividers Overview

The MC14521BFELG is a 24-stage frequency divider manufactured by onsemi, housed in an SOEIAJ-16 package. It features a chain of flip-flops with an input circuit supporting crystal oscillators, RC oscillators, or external oscillator buffers. The device counts up to 2^24 (16,777,216) on negative clock edges and provides outputs for the last seven stages. It operates within a supply voltage range of 3.0 Vdc to 18 Vdc and supports ambient temperatures from -55°C to +125°C.

Counter Dividers Feature Summary

• Supports three distinct input modes: crystal oscillator, RC oscillator, or external oscillator buffer.
• All internal stages are individually resettable, allowing the RC oscillator to be disabled for low standby power consumption.
• Includes a dedicated test mode that divides the counter into parallel sections to reduce testing time.
• Provides accessible VDD' and VSS' pins on the crystal oscillator inverter for connecting external resistors.

Counter Dividers Applications

• Frequency division circuits requiring high stage counts
• Clock generation systems utilizing internal RC or crystal oscillators
• Digital counters and timing applications

Counter Dividers Procurement Notes

Verify the specific ordering suffix ELG corresponds to the SOEIAJ-16 tape and reel configuration containing 2000 units per reel. Confirm RoHS compliance and lead-free status as indicated by the G suffix in the base part number. Ensure the procurement documentation matches the exact datasheet revision Rev. 8 specifications for electrical characteristics.

Counter Dividers Selection Notes

Select this component when a 24-stage CMOS divider is required with integrated oscillator capabilities. It is suitable for designs needing flexible input buffering or low-power operation via resettable stages. Verify that the load requirements align with its capability to drive two low-power TTL loads or one low-power Schottky TTL load across the rated temperature range.

Counter Dividers Part Context

This device belongs to the MC14521B family of 24-stage frequency dividers produced by onsemi. It is designed for general-purpose digital logic applications requiring precise frequency division. The product line includes various packaging options such as PDIP-16, SOIC-16, and SOEIAJ-16 to accommodate different board layout constraints.

Counter Dividers Replacement Considerations

Compatible substitutes include CD4521B, HEF4521B, HCF4521B, HD14521B, and TC4521BP. Verify pinout compatibility and electrical parameters against the target application requirements before substitution.

Counter Dividers FAQ

How does the test mode function?

The test mode divides the counter into three 8-stage sections in parallel. By loading 255 counts into each section, all flip-flops are set to logic '1'. A single pulse then causes the counter to ripple from all '1's to all '0's, verifying functionality quickly.

What is the purpose of the VDD' and VSS' pins?

These pins are brought out on the crystal oscillator inverter to allow the connection of external resistors. This feature enables users to adjust the circuit for low-power operation.