BQ4847MT Real Time Clock IC Equivalent & Substitute Parts

Part Overview

The BQ4847MT is a Real Time Clock (RTC) IC with Clock/Calendar functionality in a 28-DIP Module package, manufactured by Texas Instruments. This component provides parallel interface timekeeping with alarm, daylight savings, leap year, supervisor, and watchdog timer capabilities. The product is classified as obsolete, making equivalent substitute parts necessary for new designs, maintenance, or production continuity. Substitute parts must maintain functional compatibility through equivalent interface types, time/date format support, and core RTC features while accommodating different packaging and voltage specifications.

Key Parameters

Parameter	BQ4847MT Value
Manufacturer	Texas Instruments
Category	Clock/Timing
Type	Clock/Calendar
Interface	Parallel
Package / Case	28-DIP Module (0.61", 15.49mm)
Time Format	HH:MM:SS (12/24 hr)
Date Format	YY-MM-DD-dd
Voltage - Supply	4.75V ~ 5.25V
Voltage - Supply, Battery	2.3V ~ 4V
Operating Temperature	0°C ~ 70°C
Mounting Type	Through Hole
Product Status	Obsolete
RoHS Status	ROHS3 Compliant

Substitute Part Grouping Explanation

Substitution logic for the BQ4847MT is based on the following critical parameters:

Interface Compatibility: All substitute parts maintain parallel interface operation, ensuring direct functional replacement at the signal level.

Time/Date Format: Substitute parts support HH:MM:SS (12/24 hr) and YY-MM-DD-dd formats, matching the original specification.

Core Features: Substitute parts include essential RTC features such as alarm functionality, leap year support, and calendar operation.

Voltage Specifications: Substitute parts operate within compatible supply voltage ranges. The BQ4847MT operates at 4.75V ~ 5.25V primary supply. Substitute parts are grouped by voltage compatibility: 4.5V ~ 5.5V (compatible with 5V systems) or 2.97V ~ 3.63V (3.3V systems).

Packaging Considerations: While the original uses 28-DIP Through Hole mounting, substitute parts are available in alternative packages (28-PLCC, 24-DIP, 32-DIP, 24-SOIC, 34-PowerCap) to accommodate different PCB designs and manufacturing processes.

Product Status: Active substitute parts ensure long-term availability and support compared to the obsolete original.

Parameter Comparison

Part Number	Manufacturer	Interface	Time Format	Date Format	Voltage - Supply	Voltage - Battery	Operating Temp	Package / Case	Mounting Type	Product Status
BQ4847MT	Texas Instruments	Parallel	HH:MM:SS (12/24 hr)	YY-MM-DD-dd	4.75V ~ 5.25V	2.3V ~ 4V	0°C ~ 70°C	28-DIP Module (0.61", 15.49mm)	Through Hole	Obsolete
DS12885QN+T&R	Analog Devices Inc./Maxim Integrated	Parallel	HH:MM:SS (12/24 hr)	YY-MM-DD-dd	4.5V ~ 5.5V	2.5V ~ 4V	-40°C ~ 85°C	28-LCC (J-Lead)	Surface Mount	Active
DS12887A+	Analog Devices Inc./Maxim Integrated	Parallel	HH:MM:SS (12/24 hr)	YY-MM-DD-dd	4.5V ~ 5.5V	2.5V ~ 4V	0°C ~ 70°C	24-DIP Module (0.600", 15.24mm)	Through Hole	Active
DS1554W-120IND+	Analog Devices Inc./Maxim Integrated	Parallel	HH:MM:SS (24 hr)	YY-MM-DD-dd	2.97V ~ 3.63V	—	-40°C ~ 85°C	32-DIP Module (0.600", 15.24mm)	Through Hole	Active
DS1558W+TRL	Analog Devices Inc./Maxim Integrated	Parallel	HH:MM:SS (24 hr)	YY-MM-DD-dd	2.97V ~ 3.63V	2.5V ~ 3.7V	-40°C ~ 85°C	48-LQFP	Surface Mount	Active
DS1685S-3+T&R	Analog Devices Inc./Maxim Integrated	Parallel	HH:MM:SS (12/24 hr)	YY-MM-DD-dd	2.7V ~ 3.7V	2.5V ~ 3.7V	0°C ~ 70°C	24-SOIC (0.295", 7.50mm Width)	Surface Mount	Active
DS1685SN-5+	Analog Devices Inc./Maxim Integrated	Parallel	HH:MM:SS (12/24 hr)	YY-MM-DD-dd	4.5V ~ 5.5V	2.5V ~ 3.7V	-40°C ~ 85°C	24-SOIC (0.295", 7.50mm Width)	Surface Mount	Active
DS1744P-70+	Analog Devices Inc./Maxim Integrated	Parallel	HH:MM:SS (24 hr)	YY-MM-DD-dd	4.5V ~ 5.5V	3V	0°C ~ 70°C	34-PowerCap™ Module	Surface Mount	Active
DS1744W-120+	Analog Devices Inc./Maxim Integrated	Parallel	HH:MM:SS (24 hr)	YY-MM-DD-dd	2.97V ~ 3.63V	—	0°C ~ 70°C	28-DIP Module (0.600", 15.24mm)	Through Hole	Active
DS1744WP-120IND+	Analog Devices Inc./Maxim Integrated	Parallel	HH:MM:SS (24 hr)	YY-MM-DD-dd	2.97V ~ 3.63V	3V	-40°C ~ 85°C	34-PowerCap™ Module	Surface Mount	Active
DS1746WP-120+	Analog Devices Inc./Maxim Integrated	Parallel	HH:MM:SS (24 hr)	YY-MM-DD-dd	2.97V ~ 3.63V	3V	0°C ~ 70°C	34-PowerCap™ Module	Surface Mount	Active

Engineering Selection Recommendations

For 5V System Designs with Through-Hole Mounting: DS12887A+ provides direct functional replacement with matching 0°C ~ 70°C operating temperature and 4.5V ~ 5.5V supply voltage compatibility. The 24-DIP package accommodates through-hole PCB layouts. Product status is active with ROHS3 compliance.

For 5V System Designs with Surface-Mount Packaging: DS12885QN+T&R operates at 4.5V ~ 5.5V with 28-LCC (J-Lead) surface-mount package. Extended operating temperature range (-40°C ~ 85°C) provides broader environmental tolerance. ROHS3 compliant with active product status.

For 3.3V System Designs with Through-Hole Mounting: DS1744W-120+ operates at 2.97V ~ 3.63V in 28-DIP Module package, maintaining through-hole compatibility. Operating temperature range 0°C ~ 70°C matches the original specification. Active product status ensures availability.

For 3.3V System Designs with Surface-Mount Packaging: DS1685S-3+T&R operates at 2.7V ~ 3.7V in 24-SOIC package with 0°C ~ 70°C operating temperature. Alternatively, DS1685SN-5+ supports 4.5V ~ 5.5V operation in the same 24-SOIC package for 5V systems requiring surface-mount form factor.

For Extended Temperature Range Applications: DS1685SN-5+ (4.5V ~ 5.5V, -40°C ~ 85°C) or DS1744WP-120IND+ (2.97V ~ 3.63V, -40°C ~ 85°C) provide expanded operating temperature specifications. Both are active products with ROHS3 compliance.

All substitute parts maintain ROHS3 compliance and REACH unaffected status, matching the original part's regulatory requirements.

Frequently Asked Questions (FAQ)

Q: Can DS12887A+ directly replace BQ4847MT in existing designs? A: DS12887A+ maintains parallel interface, HH:MM:SS (12/24 hr) time format, and YY-MM-DD-dd date format compatibility. Supply voltage range 4.5V ~ 5.5V encompasses the original 4.75V ~ 5.25V specification. The 24-DIP through-hole package differs from the original 28-DIP, requiring PCB layout modification.

Q: What is the primary difference between DS1744W-120+ and DS1744WP-120IND+? A: Both parts use the DS1744 base platform with 32KB memory and 2.97V ~ 3.63V supply voltage. DS1744W-120+ operates 0°C ~ 70°C in 28-DIP through-hole package. DS1744WP-120IND+ operates -40°C ~ 85°C in 34-PowerCap™ surface-mount package, providing extended temperature range and different form factor.

Q: Are all substitute parts ROHS3 compliant? A: Yes. All listed substitute parts are ROHS3 compliant and REACH unaffected, matching the original BQ4847MT regulatory status.

Q: Which substitute part supports 12/24 hour time format like the original? A: DS12885QN+T&R, DS12887A+, DS1685S-3+T&R, and DS1685SN-5+ all support HH:MM:SS (12/24 hr) format. Other substitutes support 24-hour format only.

Q: What packaging options are available for 5V operation? A: DS12887A+ (24-DIP through-hole), DS12885QN+T&R (28-LCC surface-mount), DS1685SN-5+ (24-SOIC surface-mount), and DS1744P-70+ (34-PowerCap™ surface-mount) all operate at 4.5V ~ 5.5V.

Q: Which substitute provides the closest pin-count match to the 28-DIP original? A: DS1744W-120+ uses 28-DIP through-hole package, matching the original pin count and mounting type while operating at 2.97V ~ 3.63V. DS12885QN+T&R uses 28-LCC (J-Lead) surface-mount with equivalent pin count.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message