ZDC833ATA

Overview

The ZDC833A is a silicon dual variable capacitance diode in a SOT23 package, featuring common cathode monolithic construction. Designed for VHF to UHF operation, it provides a reverse breakdown voltage of 25V and a typical diode capacitance of 33pF at 2V reverse bias. The device exhibits a capacitance ratio of 6.5 between 2V and 20V, with a figure of merit Q of 200 at 50MHz. It supports a forward current of 200mA and operates within a temperature range of -55°C to +150°C.

Feature Summary

• Monolithic dual diode configuration with common cathode connection
• Optimized for VHF to UHF frequency ranges
• High capacitance ratio for precise tuning applications

Applications

• Mobile radios and pagers
• Cellular telephones
• Voltage controlled crystal oscillators

Procurement Notes

Verify the manufacturer origin as Diodes Incorporated acquired Zetex plc assets. Confirm the specific ordering suffix matches the required tape and reel quantity or packaging format. Ensure the component date code aligns with project requirements before finalizing procurement orders.

Selection Notes

Select this component when designing circuits requiring dual varactor functionality in a compact surface-mount footprint. Evaluate the 33pF baseline capacitance and 6.5 ratio against the required tuning range. Verify that the 25V breakdown rating exceeds the maximum circuit operating voltage.

Part Context

Originally manufactured by Zetex plc, this part was integrated into Diodes Incorporated's portfolio following their acquisition of Zetex. The datasheet retains original Zetex branding and publication details from January 1998 while being distributed under the Diodes Incorporated brand.

Replacement Considerations

Check for updated revisions from Diodes Incorporated. Verify pinout compatibility if substituting with other SOT23 dual varactors. Ensure equivalent capacitance ratios and breakdown voltages are maintained for oscillator stability.