PCF8563T/5 - I2C Real-Time Clock/Calendar IC | NXP | SOIC-8
MPN: PCF8563T/5 ✓ Hoạt độngPCF8563T/5 Tóm tắt
What is a Real-Time Clock IC? An RTC is a dedicated timing integrated circuit that maintains accurate wall-clock time (seconds, minutes, hours, day, date, month, year) independent of the host system, typically backed by a small backup cell or supercapacitor. RTCs belong to the broader hierarchy of clock-and-timing ICs, which includes oscillators, PLL synthesizers and timers. Within the timekeeping sub-category, I2C RTCs such as the PCF8563 sit alongside SPI and parallel-interface RTCs, providing battery-backed timekeeping for embedded designs.
Key features of the PCF8563T/5 include an integrated 32.768 kHz oscillator (0.0320 MHz reference) that requires only an external quartz crystal, a BCD-coded register map for sub-second resolution free software access, a selectable 32.768 kHz or programmable frequency clock output on CLKOUT, and a low-battery detection flag. The integrated voltage-low detector automatically switches between main supply and backup source without external MOSFETs, simplifying battery-backed designs.
The PCF8563 uses a CMOS process with on-chip load capacitors matched to standard 32.768 kHz tuning-fork crystals, eliminating the need for external load caps in most applications. The address-and-data I2C protocol includes automatic register-increment for sequential reads (block read of all time/date registers in one transaction) and a slave address of 0x51 (write) / 0x53 (read) fixed by the part.
Typical applications include battery-backed timekeeping in metering equipment, point-of-sale terminals, data loggers, white goods and consumer electronics, industrial controllers requiring timestamps, and any embedded system needing a low-power always-on calendar function. A wide 1.8 V to 5.5 V operating range lets the same part span single-cell Li-ion designs and 5 V industrial buses.
When designing with this device, reserve the SDA and SCL pins with proper pull-ups to VCC (typically 4.7 kohm at 400 kHz), and place the 32.768 kHz crystal as close to OSCI/OSCO as possible to minimize stray capacitance. Backup-battery drain is dominated by the oscillator current; check the datasheet's Ibat figure to size your backup source.
This page synthesizes distributor pricing, drop-in alternatives and practical design notes not found in the manufacturer datasheet alone.
Bộ thay thế dễ dàng lắp đặt cho PCF8563T/5 — cùng gói, chân-to-chân tương thích. Các bộ phận yêu cầu hàn PCB bị loại trừ.
Các biến thể trong loạt này
Các mẫu cùng loạt có thể lắp đặt dễ dàng tương thích với PCF8563T/5 (cùng hình factor và footprint) — khác nhau ở Calendar Functions, Manufacturer, Package, Product Type.
PCF8563T/4
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
PCF8563T
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
PCF8563TD
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
YQ8563
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
DS1307Z+
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →MCP7940N
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
PCF8563T/5 Thông số kỹ thuật
| Device Type | Real-Time Clock / Calendar |
| Bus Interface | I2C (2-wire serial), 400 kbit/s max |
| Điện áp cung cấp | 1.8 V to 5.5 V |
| Timekeeping Reference | 32.768 kHz external crystal (0.0320 MHz nominal) |
| Hộp | SOIC-8 (SOT96-1 / MO-012), 3.90 mm body |
| Kiểu lắp đặt | Surface Mount |
| Nhiệt độ hoạt động | -40 C to +85 C |
| I2C Slave Address | 0x51 (write) / 0x53 (read) |
| Integrated Functions | Programmable CLKOUT, INT output, Voltage-low detector |
| Backup-Battery Switching | Internal, automatic (with external diode/cap) |
| Register Format | BCD-coded time/date, auto-increment on multi-byte read |
| Maximum Clock Frequency (Bus) | 400 kHz (Fast-Mode I2C) |
| Calendar Functions | Seconds, Minutes, Hours, Day, Date, Month, Year (with leap-year compensation to 2099) |
| Trạng thái RoHS | Compliant |
Cấu hình chân PCF8563T/5
| Chân 1 | OSCI — Oscillator input; connect to external 32.768 kHz crystal |
| Chân 2 | OSCO — Oscillator output; connect to external 32.768 kHz crystal |
| Chân 3 | INT — Interrupt output (open-drain, active low) |
| Chân 4 | CLKOUT — Programmable clock output (32.768 kHz default) |
| Chân 5 | GND — Ground reference |
| Chân 6 | VBACK — Backup supply input (e.g., coin cell) |
| Chân 7 | SDA — I2C serial data (open-drain, requires pull-up) |
| Chân 8 | SCL — I2C serial clock (open-drain, requires pull-up) |
Ứng dụng tiêu biểu
PCF8563T/5 phù hợp cho 6 Áp dụngs: Battery-Backed Timekeeping for Embedded MCUs, Industrial Data Loggers and Metering, Consumer Electronics and White Goods, Point-of-Sale Terminals and Vending, IoT Sensor Hubs and Edge Gateways, Automotive Dashboards and Aftermarket Modules.
Battery-Backed Timekeeping for Embedded MCUs
The PCF8563T/5 is the workhorse companion for low-power microcontrollers that must keep wall-clock time across power cycles. Its 1.8 V to 5.5 V supply range spans 3.3 V MCUs and single-cell Li-ion designs, while the integrated voltage-low detector switches automatically to a coin cell on VCC loss. Typical MCU companions such as the NXP S9S08QG4 draw microampere sleep currents, so the 0.25 uA RTC budget dominates total standby drain. Block-read of seconds-through-year registers in one I2C transaction minimizes wake time, and the 32.768 kHz CLKOUT can drive an MCU timer input for software RTC fallback. Choose this topology when an application layer needs absolute timestamps and the system can tolerate +/-20 ppm crystal drift.
Được đề xuất
Industrial Data Loggers and Metering
Industrial data loggers, electricity meters and gas meters depend on deterministic timestamps to correlate measurements with billing periods. The PCF8563T/5 provides seconds-through-century resolution in BCD format, simplifying firmware arithmetic and leap-year handling to 2099. Its wide 1.8 V to 5.5 V operating range lets the same PCB accept 24 V industrial bus rails stepped down to 3.3 V. The integrated voltage-low detector protects against brownouts that would otherwise corrupt the oscillator or time registers. Pair with a temperature-compensated MEMS oscillator or a tightened-spec 32.768 kHz crystal when metering accuracy is critical. The device's 400 kHz I2C throughput is sufficient for sub-millisecond synchronization across a meter's data acquisition front end.
Được đề xuất
Consumer Electronics and White Goods
Washing machines, microwave ovens, programmable thermostats and audio equipment all benefit from battery-backed timekeeping without the cost of an always-on host CPU. The PCF8563T/5 in SOIC-8 is small enough to fit alongside the main controller and runs reliably at the 3.3 V regulator rail of these appliances. The INT pin can wake the host MCU on a programmable alarm or timer event, enabling deep-sleep modes between scheduled operations such as defrost cycles or wash programs. The CLKOUT pin drives a status LED or 32.768 kHz timing reference without burdening the host MCU. Backup-cell switching is automatic, and the part's 8 kV HBM ESD rating (per datasheet) helps survive the harsh inrush transients of motor-driven appliances.
Được đề xuất
Point-of-Sale Terminals and Vending
Point-of-sale (POS) terminals, vending machines and ticketing systems need a tamper-resistant timestamp every transaction, even during power outages. The PCF8563T/5 maintains accurate time across main-power interruptions via its automatic VCC to VBACK switchover, and the integrated oscillator needs only an external 32.768 kHz crystal. The internal register map segregates time, date, alarm and control functions, supporting 100-year calendar arithmetic from 2000 to 2099 without host intervention. The I2C bus can be shared with EEPROM, security ICs and the printer controller, simplifying the wiring harness. Designers of unattended terminals especially value the part's low backup current, which keeps a CR2032 alive for over a decade of shelf time between battery changes.
Được đề xuất
IoT Sensor Hubs and Edge Gateways
Battery-powered IoT sensor hubs and edge gateways commonly sleep at nanoampere currents and wake periodically to forward telemetry. The PCF8563T/5 can stay alive during deep sleep on a coin cell, then interrupt the host MCU on programmable timer expiry so it does not need to track wall-clock time itself. The wide 1.8 V to 5.5 V supply range accommodates energy-harvesting boost outputs as well as standard 3.6 V Li-SOCl2 cells used in outdoor deployments. Its small SOIC-8 footprint leaves room for an NXP KW41Z or similar BLE module on the same PCB. The internal voltage-low detector allows the gateway to log the exact time of battery swap events, supporting fleet health monitoring across thousands of nodes.
Được đề xuất
Automotive Dashboards and Aftermarket Modules
Automotive dashboards, GPS trackers and aftermarket telematics units require reliable timestamps to coordinate CAN bus events and synchronize log files. While PCF8563T/5 itself is not AEC-Q100 qualified, its automotive-typical -40 C to +85 C temperature range and robust I2C interface make it well suited to in-cabin telematics black boxes and infotainment accessories operating from a regulated 5 V or 3.3 V rail. Designers pair it with a temperature-compensated oscillator when sub-second accuracy is required. The interrupt output can wake a connected MCU on alarm match, and the CLKOUT pin provides a stable 32.768 kHz source for the telematics RTC counter. The SOIC-8 package reflows cleanly on standard lead-free automotive PCB assembly lines.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho PCF8563T/5 — so sánh, hướng dẫn thiết kế và thông tin tuân thủ.
Hướng dẫn chọn lựa
So sánh với các sản phẩm thay thế
| Tham số | Sản phẩm này | PCF8563T/4 | PCF8563T | PCF8563TD | DS1307Z+ | MCP7940N |
|---|---|---|---|---|---|---|
| Package | SOIC-8 (SOT96-1) | SOIC-8 (SOT96-1) - same | SOIC-8 (SOT96-1) - same | SOIC-8 (SOT96-1) - same | SOIC-8 - same | SOIC-8 - same |
| Brand | NXP Semiconductors | NXP Semiconductors - same | NXP Semiconductors - same | NXP Semiconductors - same | Analog Devices | Microchip Technology |
| I2C Slave Address | 0x51 (write 0xA2) | 0x51 - identical | 0x51 - identical | 0x51 - identical | 0x68 | 0x57 |
| Supply Voltage | 1.8 V to 5.5 V | 1.8 V to 5.5 V | 1.8 V to 5.5 V | 1.8 V to 5.5 V | 4.5 V to 5.5 V | 1.8 V to 5.5 V |
| Backup Current (typical) | 0.25 uA | 0.25 uA | 0.25 uA | 0.25 uA | 0.5 uA | 1.2 uA |
| Integrated Crystal | No (external 32.768 kHz) | No (external) | No (external) | No (external) | No (external) | No (external) |
| Time Accuracy | Crystal-dependent (~+/-20 ppm) | Crystal-dependent | Crystal-dependent | Crystal-dependent | Crystal-dependent | Crystal-dependent w/ digital trim |
| Battery-Backed NV-RAM | No | No | No | No | 56 bytes | 64 bytes SRAM |
| I2C Max Bus Speed | 400 kHz | 400 kHz | 400 kHz | 400 kHz | 100 kHz | 400 kHz |
| Operating Temperature | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | 0 C to +70 C (commercial) | -40 C to +85 C (industrial grade) |
Bảo phân biệt quan trọng
- Lowest backup current in the SOIC-8 RTC class (vsDS1307Z+)
- Single-part 1.8 V to 5.5 V supply support (vsDS1307Z+)
- Automatic backup-battery switchover built in (vsMCP7940N)
- Identical register map across NXP PCF8563 family (vsDS1307Z+)
Ghi chú thiết kế
Place the 32.768 kHz crystal as close as possible to pins 1 (OSCI) and 2 (OSCO) with short symmetric traces to minimize stray capacitance. Keep the crystal ground return directly to the RTC GND pin (pin 5) rather than sharing a long path with high-current digital returns. Isolate the oscillator loop from switching regulators and noisy I2C traces to prevent injection of phase noise, which would otherwise degrade timekeeping accuracy beyond the crystal's specified tolerance.
Wire VBACK (pin 6) through a series Schottky diode (e.g., BAT54C) from a coin cell or supercap so the cell is reverse-blocked from being charged by VCC. The internal voltage-low detector handles the seamless source switchover when VCC falls below VBACK - typically around 2.5 V threshold per NXP datasheet. Add a 100 nF decoupling capacitor on VCC as close to the SOIC-8 body as possible, plus a 1 uF bulk cap on VBACK to absorb inrush during cell connect.
Both SDA (pin 7) and SCL (pin 8) are open-drain and require pull-up resistors to VCC; typical values are 4.7 kohm at 3.3 V for Fast-Mode 400 kHz operation, or 10 kohm at lower speeds and longer buses. The INT pin is also open-drain and must be pulled up. Validate the I2C rise time against the Fast-Mode 300 ns maximum spec, as undersized pull-ups on a long bus will degrade to Standard-Mode at 100 kHz.
The I2C slave address is fixed at 0x51 (write 0xA2, read 0xA3); firmware must use 8-bit address notation including the R/W bit. Do not confuse this with 7-bit notation 0x51 on hosts that auto-include the R/W bit. When switching to DS1307Z+ as a cross-brand alternative, update the firmware address to 0x68 - this is the most common drop-in pitfall.
Thông tin tuân thủ
RoHS and REACH compliant per NXP product page; not AEC-Q100 qualified - select AEC-Q100 RTCs for automotive under-hood applications. Halogen-free status not stated in public NXP product information; verify with manufacturer declaration if required.
