Request Quote
(Ships tomorrow)
AB1801-T3 Real Time Clock IC: Equivalent & Substitute Parts
Part Overview
The AB1801-T3 is a Real Time Clock (RTC) IC manufactured by Abracon LLC, designed for Clock/Calendar applications with I2C 2-Wire Serial interface in a 16-VFQFN Exposed Pad package. The device features alarm functionality, leap year support, and trickle-charger capability with ultra-low timekeeping current consumption of 0.17µA to 0.22µA at 1.8V to 3V. The AB1801-T3 is currently listed as obsolete, making equivalent and substitute parts necessary for ongoing design support and production continuity. The substitute parts listed maintain core RTC functionality while offering active product status and enhanced feature sets.
Substiute Parts
Key Parameters
| Parameter | AB1801-T3 Specification |
|---|---|
| Manufacturer | Abracon LLC |
| Product Status | Obsolete |
| Package / Case | 16-VFQFN Exposed Pad (3x3) |
| Type | Clock/Calendar |
| Interface | I2C, 2-Wire Serial |
| Voltage - Supply | 1.7V ~ 3.6V |
| Voltage - Supply, Battery | 1.5V ~ 3.6V |
| Current - Timekeeping (Max) | 0.17µA ~ 0.22µA @ 1.8V ~ 3V |
| Operating Temperature | -40°C ~ 85°C |
| Time Format | HH:MM:SS:hh |
| Date Format | YY-MM-DD-dd |
| Features | Alarm, Leap Year, Trickle-Charger |
| RoHS Status | ROHS3 Compliant |
| Moisture Sensitivity Level (MSL) | 1 (Unlimited) |
Substitute Part Grouping Explanation
Substitution of the AB1801-T3 is determined by the following critical parameters:
Primary Compatibility Criteria:
- I2C 2-Wire Serial interface (mandatory for software compatibility)
- Operating temperature range -40°C to 85°C (mandatory for environmental compatibility)
- RoHS3 compliance and REACH unaffected status (mandatory for regulatory compliance)
- Supply voltage overlap with 1.7V ~ 3.6V range (for low-power applications)
- Time and date format support (HH:MM:SS and YY-MM-DD minimum)
Secondary Compatibility Considerations:
- Package type (surface mount preferred for modern designs; through-hole alternatives available)
- Memory capacity (256B SRAM in AB1805-T3 provides enhanced functionality)
- Current consumption in timekeeping mode (lower is preferable for battery-backed applications)
- Feature set (alarm, leap year, trickle-charger support)
The substitute parts are grouped into two categories: direct Abracon equivalent (AB1805-T3) and manufacturer-recommended alternatives from Analog Devices Inc./Maxim Integrated and Renesas Electronics Corporation. All substitutes maintain I2C interface compatibility and operating temperature specifications. Package variations accommodate different PCB assembly requirements.
Parameter Comparison
| Parameter | AB1801-T3 | AB1805-T3 | 1337GDVGI8 | DS1307N+ | DS1308U-18+T | DS1337+ | DS1338U-33+T&R | DS1338Z-18+T&R | DS1339U-3+ | DS1339U-3+T&R | DS1388Z-5+ |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Manufacturer | Abracon LLC | Abracon LLC | Renesas Electronics | Analog Devices/Maxim | Analog Devices/Maxim | Analog Devices/Maxim | Analog Devices/Maxim | Analog Devices/Maxim | Analog Devices/Maxim | Analog Devices/Maxim | Analog Devices/Maxim |
| Product Status | Obsolete | Active | Active | Active | Active | Active | Active | Active | Active | Active | Active |
| Package / Case | 16-VFQFN (3x3) | 16-VFQFN (3x3) | 8-MSOP | 8-DIP (0.300") | 8-TSSOP/MSOP | 8-DIP (0.300") | 8-TSSOP/MSOP | 8-SOIC (0.154") | 8-TSSOP/MSOP | 8-TSSOP/MSOP | 8-SOIC (0.154") |
| Interface | I2C, 2-Wire Serial | I2C, 2-Wire Serial | I2C, 2-Wire Serial | I2C, 2-Wire Serial | I2C, 2-Wire Serial | I2C, 2-Wire Serial | I2C, 2-Wire Serial | I2C, 2-Wire Serial | I2C, 2-Wire Serial | I2C, 2-Wire Serial | I2C, 2-Wire Serial |
| Voltage - Supply | 1.7V ~ 3.6V | 1.7V ~ 3.6V | 1.8V ~ 5.5V | 4.5V ~ 5.5V | 1.71V ~ 5.5V | 1.8V ~ 5.5V | 3V ~ 5.5V | 1.71V ~ 5.5V | 2.7V ~ 5.5V | 2.7V ~ 5.5V | 4.5V ~ 5.5V |
| Voltage - Supply, Battery | 1.5V ~ 3.6V | 1.5V ~ 3.6V | Not specified | 2V ~ 4.6V | 1.3V ~ 5.5V | Not specified | 1.3V ~ 3.7V | 1.3V ~ 3.7V | 1.3V ~ 3.7V | 1.3V ~ 3.7V | 1.3V ~ 5.5V |
| Current - Timekeeping (Max) | 0.17µA ~ 0.22µA @ 1.8V ~ 3V | 0.17µA ~ 0.22µA @ 1.8V ~ 3V | 0.6µA @ 1.3V ~ 1.8V | 200µA @ 5V | 100µA @ 1.89V | 0.6µA @ 1.3V ~ 1.8V | 125µA ~ 200µA @ 3.63V ~ 5.5V | 100µA @ 1.89V | 150µA @ 3.3V | 150µA @ 3.3V | 270µA @ 4.5V ~ 5.5V |
| Operating Temperature | -40°C ~ 85°C | -40°C ~ 85°C | -40°C ~ 85°C | -40°C ~ 85°C | -40°C ~ 85°C | -40°C ~ 85°C | -40°C ~ 85°C | -40°C ~ 85°C | -40°C ~ 85°C | -40°C ~ 85°C | -40°C ~ 85°C |
| Time Format | HH:MM:SS:hh | HH:MM:SS:hh | HH:MM:SS (12/24 hr) | HH:MM:SS (12/24 hr) | HH:MM:SS (12/24 hr) | HH:MM:SS (12/24 hr) | HH:MM:SS (12/24 hr) | HH:MM:SS (12/24 hr) | HH:MM:SS (12/24 hr) | HH:MM:SS (12/24 hr) | HH:MM:SS:hh (12/24 hr) |
| Date Format | YY-MM-DD-dd | YY-MM-DD-dd | YY-MM-DD-dd | YY-MM-DD-dd | YY-MM-DD-dd | YY-MM-DD-dd | YY-MM-DD-dd | YY-MM-DD-dd | YY-MM-DD-dd | YY-MM-DD-dd | YY-MM-DD-dd |
| Memory Size | Not specified | 256B | Not specified | 56B | 56B | Not specified | 56B | 56B | Not specified | Not specified | 512B |
| Features | Alarm, Leap Year, Trickle-Charger | Alarm, Leap Year, SRAM, Trickle-Charger, Watchdog Timer | Alarm, Leap Year, Square Wave Output | Leap Year, NVSRAM, Square Wave Output | Leap Year, NVSRAM, Square Wave Output | Alarm, Leap Year, Square Wave Output | Leap Year, NVSRAM, Square Wave Output | Leap Year, NVSRAM, Square Wave Output | Alarm, Leap Year, Square Wave Output, Trickle-Charger | Alarm, Leap Year, Square Wave Output, Trickle-Charger | EEPROM, Leap Year, Supervisor, Trickle-Charger, Watchdog Timer |
| RoHS Status | ROHS3 Compliant | ROHS3 Compliant | ROHS3 Compliant | ROHS3 Compliant | ROHS3 Compliant | ROHS3 Compliant | ROHS3 Compliant | ROHS3 Compliant | ROHS3 Compliant | ROHS3 Compliant | ROHS3 Compliant |
| Moisture Sensitivity Level (MSL) | 1 (Unlimited) | 1 (Unlimited) | 3 (168 Hours) | 1 (Unlimited) | 1 (Unlimited) | 1 (Unlimited) | 1 (Unlimited) | 1 (Unlimited) | 1 (Unlimited) | 1 (Unlimited) | 1 (Unlimited) |
Engineering Selection Recommendations
Direct Equivalent - AB1805-T3 (Abracon LLC)
The AB1805-T3 is the primary substitute for the obsolete AB1801-T3. Both devices share identical package geometry (16-VFQFN Exposed Pad 3x3), supply voltage range (1.7V ~ 3.6V), battery voltage range (1.5V ~ 3.6V), timekeeping current specifications (0.17µA ~ 0.22µA @ 1.8V ~ 3V), and operating temperature range (-40°C ~ 85°C). The AB1805-T3 maintains active product status with 5287 pieces in stock. Enhanced features include 256B SRAM, watchdog timer, and trickle-charger functionality. This part is recommended as the first choice for direct replacement in existing AB1801-T3 designs.
Alternative Substitutes - Analog Devices Inc./Maxim Integrated Series
The DS1337+, DS1338 series (DS1338U-33+T&R, DS1338Z-18+T&R), and DS1339 series (DS1339U-3+, DS1339U-3+T&R) provide I2C RTC functionality with active product status and ROHS3 compliance. These devices support the required YY-MM-DD-dd date format and -40°C to 85°C operating temperature. Selection among these alternatives depends on package requirements: 8-DIP for through-hole applications (DS1307N+, DS1337+), 8-TSSOP/MSOP for compact surface mount (DS1308U-18+T, DS1338U-33+T&R, DS1339U-3+, DS1339U-3+T&R), and 8-SOIC for standard surface mount (DS1338Z-18+T&R, DS1388Z-5+). The DS1388Z-5+ offers enhanced memory (512B) and supervisor functionality for applications requiring extended data storage.
Alternative Substitute - Renesas Electronics 1337GDVGI8
The 1337GDVGI8 provides I2C RTC functionality in an 8-MSOP package with active product status and ROHS3 compliance. This device supports alarm functionality, leap year, and square wave output. Supply voltage range extends to 5.5V, accommodating higher-voltage applications. Timekeeping current is 0.6µA at 1.3V ~ 1.8V. Moisture sensitivity level is MSL 3 (168 hours), requiring controlled storage conditions compared to MSL 1 alternatives.
All substitute parts maintain REACH unaffected status and EAR99 ECCN classification consistent with the AB1801-T3.
Frequently Asked Questions (FAQ)
Q: Can the AB1805-T3 directly replace the AB1801-T3 without PCB modifications?
A: Yes. The AB1805-T3 shares identical package geometry (16-VFQFN Exposed Pad 3x3), pinout compatibility, and electrical specifications with the AB1801-T3. No PCB layout changes are required. The AB1805-T3 is pin-compatible and functionally compatible for I2C-based RTC applications.
Q: What are the key differences between the Abracon AB1805-T3 and Analog Devices DS1337+ alternatives?
A: The AB1805-T3 maintains the 16-pin VFQFN package and ultra-low supply voltage range (1.7V ~ 3.6V) with 0.17µA ~ 0.22µA timekeeping current. The DS1337+ uses an 8-pin DIP package, requires minimum 1.8V supply, and consumes 0.6µA in timekeeping mode. Package selection determines suitability: AB1805-T3 for compact designs, DS1337+ for through-hole or legacy board compatibility.
Q: Are all substitute parts RoHS3 compliant?
A: Yes. All listed substitute parts (AB1805-T3, 1337GDVGI8, DS1307N+, DS1308U-18+T, DS1337+, DS1338U-33+T&R, DS1338Z-18+T&R, DS1339U-3+, DS1339U-3+T&R, DS1388Z-5+) are ROHS3 compliant and REACH unaffected, meeting current regulatory requirements.
Q: Which substitute part offers the lowest timekeeping current consumption?
A: The AB1805-T3 and AB1801-T3 both specify 0.17µA ~ 0.22µA timekeeping current at 1.8V ~ 3V, the lowest among all listed substitutes. The 1337GDVGI8 and DS1337+ follow with 0.6µA at 1.3V ~ 1.8V. For battery-backed applications requiring extended runtime, the Abracon devices are preferred.
Q: What is the difference between MSL 1 and MSL 3 moisture sensitivity?
A: MSL 1 (Unlimited) allows indefinite storage without moisture control. MSL 3 (168 Hours) requires storage in controlled humidity conditions and limits shelf life to 168 hours after bag opening. The 1337GDVGI8 is MSL 3; all other substitutes are MSL 1. MSL 1 parts are preferred for inventory management and supply chain flexibility.
Q: Can I use the DS1388Z-5+ as a direct replacement for the AB1801-T3?
A: The DS1388Z-5+ provides I2C RTC functionality with compatible date/time formats and operating temperature range. However, it uses an 8-SOIC package instead of the 16-VFQFN package, requiring PCB redesign. Supply voltage minimum is 4.5V (versus 1.7V for AB1801-T3), limiting low-power battery applications. The DS1388Z-5+ is suitable for 5V systems requiring enhanced memory (512B) and supervisor features, not as a direct pin-compatible replacement.
Q: Which substitute parts support trickle-charger functionality?
A: The AB1805-T3, DS1339U-3+, DS1339U-3+T&R, and DS1388Z-5+ include trickle-charger features. The AB1805-T3 maintains identical trickle-charger specifications to the AB1801-T3. The DS1339 series and DS1388Z-5+ provide trickle-charger support for supercapacitor or rechargeable battery backup applications.
Q: What packaging options are available for surface mount applications?
A: Surface mount alternatives include 16-VFQFN (AB1805-T3), 8-MSOP (1337GDVGI8), 8-TSSOP/MSOP (DS1308U-18+T, DS1338U-33+T&R, DS1339U-3+, DS1339U-3+T&R), and 8-SOIC (DS1338Z-18+T&R, DS1388Z-5+). The AB1805-T3 maintains the original 16-pin VFQFN footprint. Smaller 8-pin packages reduce PCB area but require firmware compatibility verification.
Alternative Parts
SJ6012L2TP
Littelfuse Inc.
6 Alternative Parts
JMK107BBJ476MA-RE
Taiyo Yuden
10 Alternative Parts
GMK107BBJ475MA-T
Taiyo Yuden
5 Alternative Parts
SJ6020N2ARP
Littelfuse Inc.
3 Alternative Parts
SJ6025R2ATP
Littelfuse Inc.
4 Alternative Parts
2474-05L
API Delevan Inc.
1 Alternative Parts
4590R-684K
API Delevan Inc.
1 Alternative Parts
CM6560R-334
API Delevan Inc.
1 Alternative Parts
CM6460-104
API Delevan Inc.
1 Alternative Parts
5526-12
API Delevan Inc.
1 Alternative Parts