PT7C4302ZEE Equivalent & Substitute Parts

Part Overview

The PT7C4302ZEE is a Real Time Clock (RTC) IC with integrated Clock/Calendar functionality, manufactured by Diodes Incorporated. This device provides 31 bytes of NVSRAM, 3-Wire Serial interface, and operates across a wide supply voltage range of 1.2V to 5.5V. The product is currently classified as Obsolete, making identification of functionally equivalent alternatives essential for ongoing system support and new design implementations.

Substiute Parts

PT7C4302ZEE

Diodes IncorporatedIn Stock: 1044PT7C4302ZEE Datasheet

Current PartRFQ

DS1302SN+

Analog Devices Inc./Maxim IntegratedIn Stock: 1147DS1302SN+ Datasheet

MFR RecommendedRFQ

DS1305EN+T&R

Analog Devices Inc./Maxim IntegratedIn Stock: 11184DS1305EN+T&R Datasheet

MFR RecommendedRFQ

DS1393U-33+

Analog Devices Inc./Maxim IntegratedIn Stock: 1295DS1393U-33+ Datasheet

MFR RecommendedRFQ

S-35190A-I8T1U

ABLIC Inc.In Stock: 3016S-35190A-I8T1U Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the PT7C4302ZEE is determined by the following critical parameters:

Interface Compatibility: The 3-Wire Serial interface is the primary functional requirement. Substitute parts must support this communication protocol.

Functional Features: Leap Year support, NVSRAM, and Trickle-Charger functionality are core to the PT7C4302ZEE operation.

Electrical Specifications: Operating temperature range (-40°C ~ 85°C), supply voltage compatibility, and timekeeping current consumption must align with system requirements.

Package Considerations: While the original uses 8-WFDFN, substitute parts may use alternative 8-pin surface mount packages (8-SOIC, 8-SMD) provided pin configuration and electrical characteristics remain compatible.

Product Status: Active status substitutes are preferred for long-term availability and supply chain stability.

The four identified substitutes meet these criteria through equivalent 3-Wire Serial interface, matching time/date formats, overlapping voltage ranges, and comparable operating temperatures.

Parameter Comparison

Engineering Selection Recommendations

DS1302SN+ (Primary Substitute): This part offers the closest functional equivalence to the PT7C4302ZEE. Both devices provide 31 bytes of memory, 3-Wire Serial interface, and identical time/date formats. The DS1302SN+ is in Active product status with established supply availability. The primary trade-off is a narrower supply voltage range (2V minimum versus 1.2V minimum). Package transition from 8-WFDFN to 8-SOIC requires PCB layout modification but maintains 8-pin configuration.

DS1305EN+T&R (Extended Memory Alternative): This substitute provides expanded 96-byte memory capacity and includes an Alarm feature not present in the PT7C4302ZEE. However, it uses SPI interface instead of 3-Wire Serial, requiring firmware and hardware interface redesign. This option is suitable only when system architecture can accommodate SPI protocol implementation.

DS1393U-33+ (Compact Package Alternative): This device maintains 3-Wire Serial interface and includes Alarm and Square Wave Output features. The 10-pin package (10-TFSOP/10-MSOP) differs from the original 8-pin configuration. Higher timekeeping current consumption (175µA) may impact battery-backed operation. Suitable for applications where additional features justify package size increase.

S-35190A-I8T1U (Low-Power Alternative): This ABLIC part offers the lowest timekeeping current consumption (0.93µA ~ 1.1µA) and maintains 3-Wire Serial interface with matching time/date formats. The 8-SMD package provides similar footprint to the original. Battery supply voltage specification is not provided. Recommended for ultra-low-power applications where current consumption is critical.

All substitutes maintain ROHS3 compliance and -40°C ~ 85°C operating temperature range.

Frequently Asked Questions (FAQ)

Q: Can DS1305EN+T&R directly replace PT7C4302ZEE without firmware changes?

A: No. The DS1305EN+T&R uses SPI interface while PT7C4302ZEE uses 3-Wire Serial. This requires firmware modification and hardware interface redesign. The DS1302SN+ is the recommended direct substitute for minimal firmware impact.

Q: What is the primary difference between 3-Wire Serial and SPI interfaces in these RTC devices?

A: 3-Wire Serial uses dedicated Clock, Data, and Chip Select lines with a simpler protocol. SPI uses Clock, MOSI, MISO, and Chip Select lines with different timing requirements. Existing 3-Wire Serial firmware cannot operate SPI devices without protocol layer rewriting.

Q: Does the package change from 8-WFDFN to 8-SOIC affect electrical performance?

A: No. Both packages are 8-pin surface mount with equivalent electrical characteristics. The change is mechanical only, requiring PCB layout modification but not affecting circuit functionality or performance.

Q: Which substitute offers the best battery backup performance?

A: The S-35190A-I8T1U provides the lowest timekeeping current at 0.93µA ~ 1.1µA, extending battery life significantly compared to the PT7C4302ZEE at 25.3µA ~ 81µA. The DS1302SN+ also offers improved efficiency at 0.3µA ~ 1µA.

Q: Are all substitutes available in the same packaging options?

A: No. Each substitute uses different package types: DS1302SN+ uses 8-SOIC, DS1305EN+T&R uses 20-TSSOP, DS1393U-33+ uses 10-TFSOP/10-MSOP, and S-35190A-I8T1U uses 8-SMD. Package selection depends on PCB design constraints and available board space.

Q: What is the minimum supply voltage requirement for each substitute?

A: PT7C4302ZEE: 1.2V; DS1302SN+: 2V; DS1305EN+T&R: 2V; DS1393U-33+: 2.97V; S-35190A-I8T1U: 1.3V. Systems operating below 2V require either the original part or S-35190A-I8T1U.

Q: Do all substitutes support both 12-hour and 24-hour time formats?

A: Yes. All substitutes support HH:MM:SS format with selectable 12/24-hour operation. The DS1393U-33+ additionally includes hundredths of seconds (HH:MM:SS:hh) capability.