Overview
The DS1339U-33+T&R is a serial real-time clock (RTC) produced by Analog Devices Inc./Maxim Integrated. This low-power clock/date device is designed to manage all timekeeping functions, including seconds, minutes, hours, date of the month, month, day of the week, and year with leap-year compensation valid up to 2100. It features two programmable time-of-day alarms and a programmable square-wave output. The device interfaces with most microcontrollers via an I²C serial interface and includes automatic power-fail detect and switch circuitry, ensuring continuous operation even during power failures.
Key Specifications
| Parameter | Symbol | Conditions | Min | Typ | Max | Units |
|---|---|---|---|---|---|---|
| Supply Voltage | VCC | - | 2.97 | 3.3 | 5.5 | V |
| Backup Supply Voltage | VBACKUP | - | 1.3 | 3.0 | 3.7 | V |
| Power-Fail Voltage | VPF | - | 2.70 | 2.85 | 2.97 | V |
| Operating Temperature Range | - | -40°C to +85°C | - | - | - | °C |
| Storage Temperature Range | - | -55°C to +125°C | - | - | - | °C |
| Package Type | - | Micro-MAX, Thin Shrink Small-Outline | - | - | - | - |
Key Features
- Completely manages all timekeeping functions, including seconds, minutes, hours, date of the month, month, day of the week, and year with leap-year compensation valid up to 2100.
- Two programmable time-of-day alarms.
- Programmable square-wave output.
- Oscillator stop flag.
- Interfaces to most microcontrollers via an I²C serial interface.
- Low-power operation extends battery backup run time.
- Automatic power-fail detect and switch circuitry.
- Trickle-charge capability.
- Underwriters Laboratories (UL) recognized.
- Surface-mount package with an integrated crystal (for certain models).
Applications
- Handheld devices (GPS, POS terminals).
- Consumer electronics (set-top boxes, digital recorders, network appliances).
- Office equipment (fax/printers, copiers).
- Medical devices (glucometers, medicine dispensers).
- Telecommunications (routers, switches, servers).
- Utility meters.
- Vending machines.
- Thermostats.
- Modems.
Q & A
- What is the primary function of the DS1339U-33+T&R?
The primary function is to manage all timekeeping functions, including seconds, minutes, hours, date of the month, month, day of the week, and year with leap-year compensation.
- What type of interface does the DS1339U-33+T&R use?
The device uses an I²C serial interface to transfer address and data.
- What are the key features of the DS1339U-33+T&R?
Key features include two programmable time-of-day alarms, a programmable square-wave output, oscillator stop flag, and automatic power-fail detect and switch circuitry.
- What is the operating temperature range of the DS1339U-33+T&R?
The operating temperature range is -40°C to +85°C.
- What type of package does the DS1339U-33+T&R come in?
The device comes in a Micro-MAX, Thin Shrink Small-Outline package.
- Is the DS1339U-33+T&R RoHS compliant?
No, the DS1339U-33+T&R is not RoHS compliant.
- What are some common applications of the DS1339U-33+T&R?
Common applications include handheld devices, consumer electronics, office equipment, medical devices, and telecommunications equipment.
- Does the DS1339U-33+T&R have a built-in power-sense circuit?
Yes, the device has a built-in power-sense circuit that detects power failures and automatically switches to the backup supply.
- Can the DS1339U-33+T&R operate in both 24-hour and 12-hour formats?
Yes, the clock operates in either the 24-hour or 12-hour format with an AM/PM indicator.
- What is the purpose of the trickle-charge capability in the DS1339U-33+T&R?
The trickle-charge capability allows the device to maintain its timekeeping functions even when the primary power source is unavailable.
