AD9765AST Equivalent & Substitute Parts

Part Overview

The AD9765AST is a 12-bit digital-to-analog converter (DAC) manufactured by Analog Devices Inc., housed in a 48-LQFP (7x7) surface mount package. This component is classified as obsolete, making identification of functionally equivalent alternatives essential for ongoing system support and new design implementations. The AD9765AST operates as a current-output DAC with dual converters, supporting both external and internal reference configurations across a 3V to 5.5V supply range.

Substiute Parts

AD9765AST

Analog Devices Inc.In Stock: 1320AD9765AST Datasheet

Current PartRFQ

AD9765ASTZ

Analog Devices Inc.In Stock: 4428AD9765ASTZ Datasheet

DirectRFQ

DAC2902Y/1K

Texas InstrumentsIn Stock: 2158DAC2902Y/1K Datasheet

DirectRFQ

DAC5662IPFB

Texas InstrumentsIn Stock: 1957DAC5662IPFB Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the AD9765AST is determined by the following core parameters:

• Resolution: 12-bit conversion capability
• Converter Count: Dual D/A converters (2 channels)
• Output Architecture: Current-output, unbuffered configuration
• Differential Output: Dual differential output capability
• Data Interface: Parallel digital input
• Reference Configuration: Support for both external and internal references
• Supply Voltage Compatibility: Analog and digital supply ranges
• Package Compatibility: 48-pin LQFP or TQFP surface mount packages
• Operating Temperature Range: -40°C to 85°C
• Compliance: RoHS3 compliance for new designs

The substitute parts identified—AD9765ASTZ, DAC2902Y/1K, and DAC5662IPFB—meet these core functional requirements with variations in settling time, linearity specifications, and supply voltage ranges.

Parameter Comparison

Engineering Selection Recommendations

AD9765ASTZ (Direct Analog Devices Substitute): This is the active-production equivalent within the Analog Devices TxDAC+ series. It maintains identical package geometry (48-LQFP 7x7), supply voltage ranges (3V–5.5V analog, 2.7V–5.5V digital), and functional architecture. The AD9765ASTZ offers improved linearity specifications (INL/DNL: ±0.4/±0.3 LSB) and faster settling time (35ns typical). RoHS3 compliance and lower MSL rating (3, 168 hours) support modern manufacturing environments. This option is preferred for direct replacement in existing designs.

DAC2902Y/1K (Texas Instruments Alternative): This Texas Instruments 12-bit dual DAC operates in the same functional class with comparable supply voltage ranges (3V–5.5V analog, 3V–5.5V digital) and identical operating temperature range. The 48-TQFP package provides mechanical compatibility with minor PCB layout considerations. Settling time of 30ns and linearity of ±1/±1 LSB represent acceptable performance for applications not requiring the precision of the AD9765ASTZ. MSL rating of 2 (1 year) provides superior moisture handling. RoHS3 compliance is confirmed.

DAC5662IPFB (Texas Instruments High-Performance Alternative): This component delivers the fastest settling time (20ns typical) and superior linearity (INL/DNL: 0.3/0.2 LSB) among the substitutes. However, the restricted supply voltage range (3V–3.6V analog and digital) limits applicability to 3.3V systems only. The 48-TQFP package and MSL rating of 2 (1 year) match the DAC2902Y/1K. RoHS3 compliance is confirmed. Selection of this part requires verification that system supply voltages remain within the 3V–3.6V window.

Frequently Asked Questions (FAQ)

Q: Can the AD9765ASTZ directly replace the AD9765AST without PCB modifications?

A: Yes. Both components use the 48-LQFP (7x7) package with identical pinout and functional specifications. No PCB layout changes are required for direct substitution.

Q: What are the package differences between LQFP and TQFP variants?

A: LQFP (Low-Profile Quad Flat Package) and TQFP (Thin Quad Flat Package) are both 48-pin surface mount packages with 7x7mm footprints. The primary difference is profile height. PCB footprints are mechanically compatible, though solder reflow profiles may require minor adjustment. Consult component datasheets for specific thermal and mechanical specifications.

Q: Which substitute offers the best linearity performance?

A: The DAC5662IPFB provides the superior linearity specification (INL/DNL: 0.3/0.2 LSB) and fastest settling time (20ns). However, this advantage is constrained to 3V–3.6V supply voltage operation. For systems operating at 5V or requiring the full 3V–5.5V range, the AD9765ASTZ (INL/DNL: ±0.4/±0.3 LSB) is the optimal choice.

Q: Are all substitute parts RoHS3 compliant?

A: Yes. The AD9765ASTZ, DAC2902Y/1K, and DAC5662IPFB are all confirmed RoHS3 compliant, supporting modern manufacturing and environmental requirements.

Q: What is the significance of the MSL (Moisture Sensitivity Level) rating difference?

A: The AD9765AST and AD9765ASTZ carry MSL 3 (168-hour floor life), while the Texas Instruments alternatives carry MSL 2 (1-year floor life). MSL 2 provides extended shelf life and reduced risk of moisture-induced failures during storage and handling. For high-volume or long-lead-time procurement, MSL 2 components offer operational advantages.

Q: Can the DAC5662IPFB be used in a 5V system?

A: No. The DAC5662IPFB is specified for 3V–3.6V operation only. Use in 5V systems will result in component damage or malfunction. Verify system supply voltages before selection.

Q: What is the difference between "Direct" and "Similar" substitute classifications?

A: Direct substitutes (AD9765ASTZ, DAC2902Y/1K) maintain full functional and electrical equivalence within specified operating ranges. Similar substitutes (DAC5662IPFB) meet core functional requirements but with restricted operating parameters (supply voltage range). Selection depends on system design constraints.