My Inquiry
My Account
Analog Devices Inc./Maxim Integrated DS1315E-5+
- Part No.:
- DS1315E-5+
- Manufacturer:
- Analog Devices Inc./Maxim Integrated
- Category:
- Real Time Clocks
- Package:
- 20-TSSOP (0.173", 4.40mm Width)
- Datasheet:
-
DS1315E-5+.pdf
- Description:
- IC RTC PHANTOM CHIP PAR 20TSSOP
- Quantity:
- Payment:
- Shipping:
Inventory:1,242
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
DS1315E-5+ from Maxim Integrated is a real-time clock (RTC) and nonvolatile memory controller IC combining timekeeping (hundredths of seconds to years, with automatic leap-year correction through 2100) and battery-backed SRAM support in a single 20-pin TSSOP package operating at +5V. It interfaces with external CMOS RAM/ROM without memory gaps and provides dual-battery redundancy for high-reliability industrial systems.
For engineers reviewing the DS1315E-5+ datasheet, DS1315E-5+ pinout, DS1315E-5+ application, or DS1315E-5+ equivalent, this page delivers verified timing accuracy, battery switchover behavior, power-fail detection thresholds, and serial pattern-access protocol details essential for embedded system design and BOM validation.
Technical Context
The DS1315E-5+ implements a 64-bit serial pattern recognition protocol (C5h, 3Ah, A3h, 5Ch repeated) to gate access to its eight BCD-formatted time registers, isolating RTC operations from memory bus traffic via CEO pin control. Its internal oscillator drives from a 32.768kHz crystal connected to X1/X2 with 6pF load capacitance requirement.
As a nonvolatile controller, it supports RAM mode (ROM/RAM = GND) with VCC0 output supplying uninterrupted power to external SRAM at ≤0.3V drop, and ROM mode (ROM/RAM = VCC0) with CEO forced low during power fail. Power-fail detection triggers at VPF = 4.25–4.5V (5V operation), initiating automatic battery selection between BAT1 and BAT2 based on voltage ranking.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Supply Voltage | +5V nominal, ±10% operating range (4.5V–5.5V) - enables direct compatibility with legacy 5V logic systems without level shifting. |
| Timekeeping Range | Hundredths of seconds to year 2100 with automatic leap-year correction - eliminates firmware calendar logic for long-life deployments. |
| Operating Temperature | 0°C to +70°C - validated for commercial-grade embedded applications including point-of-sale and industrial HMI. |
| Package | 20-pin TSSOP (4.4mm width) - surface-mount footprint with 0.65mm pitch, optimized for space-constrained PCB layouts. |
| Power-Fail Threshold | VPF = 4.25–4.5V - precise bandgap-based detection ensures reliable SRAM write protection before VCC collapse. |
| Battery Switchover | Automatic selection between BAT1 and BAT2 based on higher voltage - sustains VCC0 output without external diode-or circuitry. |
| Crystal Load | 6pF - specifies exact CL requirement for stable 32.768kHz oscillation; deviation risks timing drift or startup failure. |
Pinout & Package
DS1315E-5+ uses a 20-pin TSSOP (4.4mm body width) package with exposed pad (not electrically connected). Pin 1 is marked by a dot or beveled corner; pins are numbered counter-clockwise from pin 1.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| X1, X2 | Crystal oscillator inputs | Direct connection point for 32.768kHz tuning fork crystal; requires 6pF load capacitance for ±20ppm accuracy. |
| WE | Write enable control | Active-low signal enabling data writes during pattern recognition or time register updates; must meet tWP ≥55ns minimum pulse width. |
| BAT1, BAT2 | Redundant battery inputs | Independent backup power sources; internal comparator selects higher-voltage source to drive VCC0 during main supply loss. |
| GND | Ground reference | Two dedicated ground pins (pins 6 and 10) reduce noise coupling into sensitive RTC and memory interface circuits. |
| D, Q | Serial data I/O | Single-wire bidirectional interface for 64-bit pattern entry and time register read/write; no address lines required. |
| ROM/RAM | Memory mode select | Logic low configures nonvolatile SRAM controller with VCC0 output; logic high configures ROM interface with CEO forced low on power fail. |
| CEO, CEI, OE | Memory bus control | CEO outputs chip-enable state to external memory; CEI and OE synchronize read/write cycles with external logic; all meet tCO/tOE ≤55ns (5V). |
| RST | Hardware reset input | Asynchronous active-low reset aborts ongoing transfers without altering time registers; requires tRST ≥65ns pulse width. |
| VCC1, VCC0 | Main supply / switched output | VCC1 powers internal circuitry; VCC0 delivers regulated backup power to SRAM with ≤0.3V dropout, enabling true nonvolatility. |
Key Features
| Feature | Design Value |
|---|---|
| No address bus required | Eliminates address decoding logic and reduces MCU GPIO count by using 64-bit serial pattern access instead of parallel addressing. |
| Dual-battery support | Enables field-replaceable battery maintenance without system downtime; automatic switchover prevents VCC0 interruption during battery swap. |
| Leap-year correction to 2100 | Removes need for periodic firmware updates to calendar algorithms, critical for unattended infrastructure monitoring systems. |
| Full ±10% VCC tolerance | Accepts brownout conditions down to 4.5V without RTC stoppage or register corruption, improving resilience in noisy power environments. |
| Industrial-grade temperature option | DS1315EN-5+ variant extends operation to –40°C to +85°C, supporting deployment in outdoor kiosks and factory automation controllers. |
Applications
| Point-of-Sale Terminals | Industrial Programmable Logic Controllers |
|---|---|
|
Use Scenario: Maintaining accurate transaction timestamps and audit logs across daily power cycles and battery replacements. IC Role / Device Role / Timing Role: Primary real-time clock and nonvolatile SRAM controller ensuring timestamp continuity and configuration retention. Use Value: Eliminates timestamp gaps during AC power loss; dual-battery support allows hot-swap maintenance without log corruption. |
Use Scenario: Preserving runtime parameters, event histories, and calibration data in PLCs subjected to frequent power interruptions. IC Role / Device Role / Timing Role: Timekeeping and battery-backed memory supervisor managing SRAM data integrity during brownouts. Use Value: Prevents loss of critical operational data during factory line shutdowns; VPF-triggered write protection avoids partial writes. |
| Medical Diagnostic Equipment | Smart Energy Meters |
|
Use Scenario: Recording patient session start/end times and device calibration cycles with traceable, tamper-resistant timestamps. IC Role / Device Role / Timing Role: Secure RTC with BCD time registers and pattern-locked access preventing unauthorized time manipulation. Use Value: Meets IEC 62304 timestamp requirements; automatic leap-year correction ensures long-term date validity without service visits. |
Use Scenario: Logging energy consumption intervals and tariff-switching events over 15+ year meter lifespans with utility-grade accuracy. IC Role / Device Role / Timing Role: High-stability timekeeper synchronized to grid frequency references and backed by redundant batteries. Use Value: Achieves ±20ppm timing accuracy over temperature; 2100 leap-year support guarantees billing integrity beyond 2050. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar real-time clock and nonvolatile memory controller applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| DS1307+T&R | Lacks nonvolatile memory controller; only RTC function with I²C interface and no pattern recognition or CEO pin. | Suitable for simple timekeeping where external battery-backed RAM is separately managed. | Select DS1315E-5+ when integrated SRAM power management and bus isolation are required; DS1307+T&R only when I²C simplicity suffices. |
| M41T81SM6TR | Serial SPI interface, no dual-battery support, fixed 3.3V operation, no pattern recognition protocol. | Designed for compact SPI-based microcontrollers; lacks VCC0 output and automatic battery switchover. | Choose DS1315E-5+ for 5V systems needing robust power-fail response and hardware-level memory isolation; M41T81SM6TR for SPI-constrained designs. |
Compared with DS1307+T&R and M41T81SM6TR, DS1315E-5+ uniquely integrates timekeeping, pattern-gated register access, and dual-battery-controlled VCC0 output in a single 5V-compatible device-enabling zero-software RTC initialization and eliminating external power-path diodes or supervisors.
Availability
DS1315E-5+ is available at Aetrix Electronics and suitable for point-of-sale terminals, industrial programmable logic controllers, and smart energy meters requiring stable component supply, long-lifecycle support, and RoHS-compliant packaging.
Supply support for DS1315E-5+ includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
Maxim Integrated (now part of Analog Devices) designs precision analog, mixed-signal, and digital ICs for industrial, medical, communications, and consumer applications.
The DS1315E-5+ belongs to Maxim's Phantom Time Chip family, engineered to unify real-time clock functionality with nonvolatile memory control-reducing system-level complexity in battery-critical embedded applications.
FAQ
What is the primary function of the DS1315E-5+?
The DS1315E-5+ is a combined real-time clock and nonvolatile memory controller IC. It maintains accurate time (hundredths of seconds to years with leap-year correction through 2100) while providing battery-backed power to external CMOS SRAM via its VCC0 output. Its unique 64-bit serial pattern recognition protocol isolates RTC access from memory bus operations, making DS1315E-5+ ideal for systems requiring guaranteed timestamp integrity and seamless SRAM retention during power loss.
Does DS1315E-5+ require an external crystal?
Yes, DS1315E-5+ requires an external 32.768kHz quartz crystal connected to pins X1 and X2. The crystal must have a specified load capacitance (CL) of 6 pF to ensure stable oscillation and ±20ppm timing accuracy across temperature. No internal oscillator is provided; DS1315E-5+ relies entirely on this external crystal for timebase generation.
How does the dual-battery feature work on DS1315E-5+?
DS1315E-5+ monitors BAT1 and BAT2 inputs continuously and automatically selects the higher-voltage source to drive VCC0 during main supply (VCC1) failure. This switchover occurs without interruption to external SRAM, enabling hot-swap battery replacement. If only one battery is used, the unused input must be grounded per datasheet guidance to prevent undefined behavior in DS1315E-5+ operation.
What is the purpose of the 64-bit pattern recognition sequence in DS1315E-5+?
The 64-bit pattern (C5h, 3Ah, A3h, 5Ch repeated) serves as a hardware-level access key to the DS1315E-5+ time registers. Until this exact sequence is written consecutively via the D pin, all bus activity is routed to external memory through CEO. This prevents accidental or malicious modification of time data and eliminates the need for software-managed address decoding-making DS1315E-5+ inherently secure against unintended RTC register writes.
Can DS1315E-5+ operate with 3.3V logic levels?
No, DS1315E-5+ is specifically rated for +5V operation (4.5V–5.5V). For 3.3V systems, the pin-compatible DS1315E-33+ variant must be used. Attempting to power DS1315E-5+ from 3.3V violates its recommended operating conditions and will result in unreliable timekeeping, failed pattern recognition, and improper VCC0 regulation-compromising the core functionality of DS1315E-5+.
DS1315E-5+ Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc./Maxim Integrated
- Series:
- -
- Package/Case:
- 20-TSSOP (0.173", 4.40mm Width)
- Packaging:
- Tube
- Product Status:
- Active
- Programmable:
- Not Verified
- Type:
- Phantom Time Chip
- Features:
- Leap Year
- Memory Size:
- -
- Time Format:
- HH:MM:SS:hh (12/24 hr)
- Date Format:
- YY-MM-DD-dd
- Interface:
- Parallel
- Voltage - Supply:
- 4.5V ~ 5.5V
- Voltage - Supply, Battery:
- 2.5V ~ 3.7V
- Current - Timekeeping (Max):
- 1.3mA @ 5V
- Operating Temperature:
- 0°C ~ 70°C
- Mounting Type:
- Surface Mount
- Grade:
- -
- Qualification:
- -
- Supplier Device Package:
- 20-TSSOP
DS1315E-5+ FAQ
1.How can I place an order for DS1315E-5+ through Aetrix?
Please submit a Request for Quotation (RFQ) for DS1315E-5+ on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for DS1315E-5+ reliable?
The price and inventory of DS1315E-5+ are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for DS1315E-5+ is usually 5 days.
3.What payment methods are accepted for DS1315E-5+?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for DS1315E-5+ transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for DS1315E-5+?
DS1315E-5+ orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your DS1315E-5+ order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for DS1315E-5+?
For technical support, including DS1315E-5+ datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your DS1315E-5+ requirements.
6.How does Aetrix verify that DS1315E-5+ is sourced from the original manufacturer or authorized distributors?
All DS1315E-5+ products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that DS1315E-5+ meets industry standards.
7.What is the process for return or replacement of DS1315E-5+?
All DS1315E-5+ units undergo pre-shipment inspection (PSI). If there is an issue with DS1315E-5+, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The DS1315E-5+ part is unused and in its original packaging.
Return procedure for DS1315E-5+:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
DS1315E-5+ Tags
-
MCP7940N-I/SN
Microchip Technology
-
MCP7940MT-I/MNY
Microchip Technology
-
PCF85063ATL/1,118
NXP USA Inc.
-
MCP7940NT-I/SN
Microchip Technology
-
MCP7940NT-I/MS
Microchip Technology
-
MCP7940N-I/MS
Microchip Technology
-
PCF85063AT/AY
NXP USA Inc.
-
PCF85063TP/1Z
NXP Semiconductors
-
PCF85063ATT/AJ
NXP USA Inc.
-
MCP7940NT-E/SN
Microchip Technology
-
MCP7940NT-I/MNY
Microchip Technology
-
MCP79400T-I/SN
Microchip Technology
Tech Hub
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
