Make this my favourite USB-RTC Module (Real-Time Clock)

Raspberry Pi >> Add-ons
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Fixed Price Multiple Items
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Seller location:
Oswestry, Shropshire, United Kingdom
Ending in:
14 days, 04h:34m:30s
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Latest buyer:
b***c (4)
Fixed price:
£30.00 Buy now!
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From only £2.70
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Item Number : 60371

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Happy to combine orders - please request an invoice if ordering more than one different item.  EU customers - we now collect local VAT on your orders (with only £4+VAT handling fee) to make it easier.

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Fixed price: £30.00
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This is a Real-Time Clock (RTC) module which connects via a USB port.  Designed using the DS3231 chip, this is designed to keep time with accuracy even if a device is not connected to the internet, and even allows you to adjust time keeping by reference to the onboard temperature of the chip.

Ideal for the Raspberry Pi / Odroid C1 / Windows PCs which do not have an internet connection in order to maintain the current date and time following a reset.

We have written our own software for use with this module:

- Linux Set time and date

- Linux Read the time and date from the USB-RTC on startup

- Windows Set time and date

- Windows Read the time and date from the USB-RTC on startup.

Ideal for use with the Raspberry Pi where other RTC modules need access to GPIO header pins and they are in use by other hardware such as the Retro-Printer Module.

Includes a CR1220 3V battery (we may need to remove this for shipping to certain countries) and a plastic case.


USB Real Time Clock For Raspberry Pi

The DS3231, a true I2C is your highly effective IC that runs on the USB RTC using excessively large efficiency at low price. Our team acquired the USB-RTC to execute a precise I2C real-time clock (RTC) using an integrated temperature-compensated crystal oscillator (TCXO) and crystal-clear. Even the USB RTC comprises a crystal resonator which tends to make an increment in the efficacy of this apparatus to get its very long run using the decline of piece-part count in a manufacturing line. We build USB RTC with advanced level chip DS3231 for the commercial in addition to industrial temperature ranges also it has a 16-pin, 300-mil S O package. Acutely accurate I2C Real time clock (RTC)· 16-pin, 300-mil S O bundle·

  • Extremely accurate I2C real-time clock (RTC)
  • Integrated temperature-compensated crystal oscillator (TCXO)
  • Incorporates a battery input
  • 16-pin, 300-mil SO package
  • Automated Backup Power Supply
  • Fast (400kHz) I2C Interface

USB Real Time Clock For Raspberry Pi  can be really a highly effective device that an individual can merely plugin together with their platform to maintain the accurate timekeeping of this system. The USB-RTC maintains moments, minutes, hours, date, day, month, year, and fever information which aids the users to create higher level services and products and gadgets. The DS3231, a true I2C is your highly effective IC that runs on the USB RTC using excessively large efficiency at low price. Our team made the USB RTC execute a real real-time clock (RTC) using an integrated temperature-compensated crystal oscillator (TCXO) and crystal.

USB Real Time Clock For Raspberry Pi

MCP2221 is the key Part of the USB RTC module which functions like a USB 2.0 into I2C / / UART Protocol Converter together with GPIO. It supports full speed USB (1-2 Mb/s) which produces the communication between the Host and USB RTC with higher efficacy. It includes the Human Interface Device (HID) for the processor controller and I2CTM which allows better control of their user to the computer system. MCP2221 has assembled using Four GPIO lines which can be accessible for GPIO Operations which empowers the users to produce smarter technically complex products.

Features of MCP2221

  • I2C/SMBus supported clock and data lines
  • User-selectable via jumper cable for 3.3V or 5V level output (up to 500 mA)
  • Four GPIO lines that are configurable for GPIO Operations
  • Pins for Serial(UART) Communication
  • Supports full-speed USB (12 Mb/s)
  • 64-byte Transmit
  • 64-byte Receive
  • USB 2.0 Compliant

MCP2221 is actually a break out module which works like a USB interface processor to its conversion of this information transfer protocol between your computer USB and UART (Serial) and I2C. MCP2221 was made to execute the duty for being a development and test stage which is made up of a single double in-line form variable board.

USB Real Time Clock For Raspberry Pi

When we proceed into the facts afterward TCXO has come in the effort that's a vital portion of this USB RTC. TCXO or even Temperature-compensated crystal oscillator can be really a crystal oscillator having a temperature-sensitive reactance circuit in its own oscillation loop into remunerate to the features of frequency-temperature inherent into the crystal. An individual may operate the clock USB RTC in the 24hour or 12hourformat using an AM/PM indicator. There are just two cushioned Time of day alarms and a padded Square wave output signal is provided in order that an individual may utilize USB RTC in a far better method in their own endeavours. The Address and data are transferred serially through an I2C bi directional bus.

One of things which behave as the main reason behind the aggravation of a programmer or tech-enthusiast could be that the ability failures of this system. We took this issue into the consideration whilst developing the USB RTC to present the very ideal experience to the clients. There's really a precision temperature-compensated voltage reference and comparator circuit which tracks the status of VCC to find power failures of this USB RTC. It will permit the apparatus, USB RTC, by providing a reset output signal and then it automatically switches to the backup source to conduct the device using exactly the exact same. There's additionally the RST pin which works like a push button input signal for generating a µP re set.


  • Accuracy ±2ppm from 0°C to +40°C
  • Accuracy ±3.5ppm from -40°C to +85°C
  • Battery Backup Input for Continuous Timekeeping
  • Operating Temperature Ranges Commercial: 0°C to +70°C Industrial: -40°C to +85°C ♦ Low-Power Consumption
  • Real-Time Clock Counts Seconds, Minutes, Hours, Day, Date, Month, and Year with Leap Year Compensation Valid Up to 2100
  • Two Time-of-Day Alarms
  • Programmable Square-Wave Output
  • Fast (400kHz) I2C Interface
  • 3.3V Operation
  • Digital Temp Sensor Output: ±3°C Accuracy
  • Register for Aging Trim
  • RST Output/Push Button Reset Debounce Input
  • Underwriters Laboratories (UL®) Recognized


Picture gallery

  • USB-RTC Module (Real-Time Clock)
  • USB-RTC Module (Real-Time Clock)
  • USB-RTC Module (Real-Time Clock)
  • USB-RTC Module (Real-Time Clock)
  • USB-RTC Module (Real-Time Clock)

Questions and Answers

Shipping and Payment

Item Location:
Oswestry, Shropshire, United Kingdom
Shipping conditions:
Buyer pays shipping expenses
Shipping Costs:
  • To United Kingdom :
  • First Class Post : £2.70
  • Airmail Post : £5.81
  • To EU :
  • Airmail Post : £4.08 For initial item, £0.12 Per additional item
  • To Europe (Non EU) :
  • Airmail Post : £4.08 For initial item, £0.12 Per additional item
  • To Americas (Non USA) :
  • Airmail Post : £5.28 For initial item, £0.24 Per additional item
  • To Rest of World :
  • Airmail Post : £5.28 For initial item, £0.24 Per additional item
  • To USA :
  • Airmail Post : £5.28 For initial item, £0.24 Per additional item
Shipment terms:
Items normally posted within 1 working day after payment received.

We are happy to combine items in order to reduce overall shipping costs where practical.
If you want item tracking, please either use a tracked service, or ask us for information before making payment.

Return your item within 14 days (in original packaging) for a full refund (excluding the post and packing charge).
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Seller: Rich Mellor t/as RWAP Software 4 Firs Close, St. Martins, Oswestry, Shropshire, SY11 3LT, United Kingdom
All prices and shipping include VAT at 20.00% where applicable
VAT Number: GB326034531

The seller accepts all responsibility for this listing

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