ZC835ATA

Overview

The ZC835ATA is a single silicon hyperabrupt varactor diode manufactured by Diodes Incorporated, housed in an SOT-23-3 surface-mount package. It features a maximum peak reverse voltage of 25 V and operates within a junction temperature range of -55°C to 150°C. Key electrical specifications include a capacitance of 16.5 pF at 2 V and 1 MHz, with a Q factor of 300 at 3 V and 50 MHz. The device provides a capacitance ratio of 6.0 (measured as C2/C20), supporting precise frequency control applications.

Feature Summary

• Hyperabrupt capacitance-voltage characteristics for high tuning ratios
• Low reverse current to ensure minimal phase noise
• High quality factor (Q) for efficient resonance
• Compact SOT-23-3 surface-mount packaging

Applications

• Voltage-Controlled Crystal Oscillators (VCXO)
• Temperature-Compensated Crystal Oscillators (TCXO)
• Wireless communication systems
• Mobile radio frequency circuits

Procurement Notes

Verify component authenticity through authorized Diodes Incorporated distributors or certified suppliers. Confirm the specific suffix 'A' corresponds to the required tolerance and binning. Check for RoHS compliance status, as historical data indicates potential non-compliance for older batches. Ensure storage conditions maintain moisture sensitivity level 1 integrity prior to soldering.

Selection Notes

Select the ZC835ATA when a high capacitance ratio and low phase noise are critical for oscillator stability. Compare the 25 V reverse voltage rating against the maximum expected bias voltage in the circuit. Evaluate the 16.5 pF baseline capacitance to ensure it fits the target frequency range. Consider the SOT-23-3 footprint constraints during PCB layout design.

Part Context

The ZC835ATA belongs to the ZC83x series of silicon hyperabrupt varactor diodes originally developed by Zetex Semiconductors, now part of Diodes Incorporated. This family is designed for frequency control applications requiring tight capacitance tolerances. The 'A' suffix typically denotes specific manufacturing lot or tolerance variations within the standard product line.

Replacement Considerations

Direct substitutes include the ZC830ATA and ZC829ATA from the same manufacturer family. Verify pinout compatibility and exact capacitance values before substitution. Cross-reference datasheets for matching Q factors and reverse voltage ratings to ensure circuit performance parity.