PIC16C621T-20I/SO - 8-Bit 20MHz OTP MCU 1.75KB | Microchip
料号： PIC16C621T-20I/SO ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $3.2 | $3.20 |
| 10 | $2.95 | $29.50 |
| 100 | $2.6 | $260.00 |
| 500 | $2.3 | $1,150.00 |
| 1,000 | $2.05 | $2,050.00 |
| 1,100 | $1.95 | $2,145.00 |
PIC16C621T-20I/SO 概述
A microcontroller (MCU) is a single-chip computer that integrates a CPU, memory and programmable I/O peripherals. The PIC16C family belongs to Microchip's mid-range 8-bit MCU portfolio, sitting in the taxonomy: PIC16C -> PIC16 mid-range -> 8-bit PIC microcontroller -> embedded MCU -> semiconductor. Mid-range PIC MCUs use a 14-bit instruction word and Harvard architecture, balancing code density, deterministic interrupt response and low cost for legacy industrial and consumer designs.
Key features of the PIC16C621 include a built-in analog comparator, 13 digital I/O pins, a 16-bit timer/counter (Timer1) and an 8-bit timer/counter (Timer0), a Watchdog Timer with its own on-chip RC oscillator, Power-on Reset, Brown-out Reset, and an in-circuit serial programming (ICSP) interface for production-line code loading into the OTP memory. The 20 MHz oscillator provides a 200 ns instruction cycle, with most instructions completing in a single cycle.
Typical applications include appliance control, sensor signal conditioning, LED driving, simple motor control loops, and replacement of discrete logic in legacy 8-bit embedded products. Industrial operating temperature makes it suitable for factory automation modules and outdoor metering.
When designing with OTP memory, note that program code cannot be erased or rewritten - plan firmware revisions carefully or migrate to the flash-based PIC16F6xx family for design flexibility. The wide-body 18-SOIC (7.50 mm body width) provides better thermal and mechanical characteristics than the narrow 18-SOIC variant used on lower-pin-count PICs.
直接替换替代料： PIC16C621T-20I/SO ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
本系列中的变体
可与以下型号直接替换的同系列型号： PIC16C621T-20I/SO （相同外形与封装尺寸） ——差异在于 RAM Size, Operating Temperature, Package, Program Memory Size, Program Memory Type.
快速对比工具——选择替代料号进行并排对比：
PIC16C621T-20E/SO
✅ 直接替换✓ 有现货
$1.72 / 个
查看数据手册 →PIC16C621AT-20I/SO
✅ 直接替换✓ 有现货
$2.3 / 个
查看数据手册 →PIC16C621T-04I/SO
✅ 直接替换✓ 有现货
$2.85 / 个
查看数据手册 →PIC16C621T-04/SO
✅ 直接替换✓ 有现货
$1.65 / 个
查看数据手册 →PIC16F628A-I/SO
✅ 直接替换✓ 有现货
$2.32 / 个
查看数据手册 →PIC16C620T-20E/SS
✅ 直接替换✓ 有现货
$3.89 / 个
查看数据手册 →PIC16C621T-20I/SO 最大额定值与电气特性
| Core Architecture | 8-bit PIC mid-range (RISC, Harvard) |
| Instruction Set Width | 14-bit |
| 最大时钟频率 | 20 MHz |
| Instruction Cycle Time | 200 ns (at 20 MHz) |
| Program Memory Type | OTP (One-Time Programmable) |
| Program Memory Size | 1.75 KB (1K x 14) |
| Data RAM | 80 bytes |
| Data EEPROM | Not available on this device |
| I/O Pins | 13 |
| Timers | 1 x 8-bit (Timer0), 1 x 16-bit (Timer1) |
| Analog Comparator | Yes (on-chip) |
| Watchdog Timer | Yes (with dedicated on-chip RC oscillator) |
| Brown-out Reset | Yes |
| Power-on Reset | Yes |
| In-Circuit Serial Programming | Yes (ICSP) |
| Operating Voltage | 3.0 V to 6.0 V (5 V nominal) |
| 工作温度 | -40 C to +85 C (industrial) |
| 封装 | 18-SOIC (7.50 mm body width) |
| 安装类型 | Surface Mount |
PIC16C621T-20I/SO 引脚配置
| 引脚 1 | RA2/AN2/CVREF/VREF — Bidirectional I/O / analog input / comparator voltage reference |
| 引脚 2 | RA3/AN3/C1OUT — Bidirectional I/O / analog input / comparator 1 output |
| 引脚 3 | RA4/AN4/T0CKI — Bidirectional I/O / analog input / Timer0 clock input |
| 引脚 4 | RA5/MCLR/VPP — Bidirectional I/O / master clear reset (active low) / programming voltage |
| 引脚 5 | VSS — Ground reference |
| 引脚 6 | RB0/INT — Bidirectional I/O / external interrupt input |
| 引脚 7 | RB1 — Bidirectional I/O |
| 引脚 8 | RB2 — Bidirectional I/O |
| 引脚 9 | RB3 — Bidirectional I/O |
| 引脚 10 | RB4 — Bidirectional I/O |
| 引脚 11 | RB5 — Bidirectional I/O |
| 引脚 12 | RB6 — Bidirectional I/O / ICSP clock |
| 引脚 13 | RB7 — Bidirectional I/O / ICSP data |
| 引脚 14 | VDD — Positive supply voltage (3.0-6.0 V) |
| 引脚 15 | OSC2/CLKOUT — Oscillator output / clock output |
| 引脚 16 | OSC1/CLKIN — Oscillator input / external clock input |
| 引脚 17 | RA0/AN0 — Bidirectional I/O / analog input 0 |
| 引脚 18 | RA1/AN1 — Bidirectional I/O / analog input 1 |
典型应用
PIC16C621T-20I/SO 适用于 6 应用s: Appliance Control Boards, Sensor Signal Conditioning Front Ends, LED Display and Signage Drivers, Industrial Timer and Counter Modules, Simple Motor Control (DC and Stepper), Legacy Replacement of Discrete Logic.
Appliance Control Boards
The PIC16C621T-20I/SO suits appliance control boards such as washing machines, dishwashers and microwave ovens where a deterministic 8-bit controller manages user inputs, sensor feedback and actuator timing. Its 13 I/O pins cover keypads, LED indicators, relay drivers and triac interfaces, while the on-chip analog comparator handles zero-crossing detection for triac-driven heater elements. The 20 MHz clock and 200 ns instruction cycle ensure fast response to interrupts from rotary encoders and over-current sensors. Compared with newer flash MCUs, OTP memory locks firmware to prevent unauthorized code changes, a security benefit valued in white-goods production. The wide-body 18-SOIC also provides the mechanical robustness needed for through-hole-to-SMT retrofit boards in legacy appliance lines.
推荐
Sensor Signal Conditioning Front Ends
The PIC16C621T-20I/SO functions well in sensor signal conditioning front ends where its on-chip analog comparator and 13 I/O pins handle threshold detection, debouncing, and digital filtering without external op-amps. The comparator can directly compare thermocouple or thermistor voltages against an internal bandgap reference, freeing board space and BOM cost in industrial monitoring loops. Industrial -40 C to +85 C temperature operation supports outdoor and factory-floor deployments. The 1.75 KB OTP holds deterministic firmware for sensor calibration curves and digital low-pass filters. Combined with the 16-bit Timer1 for precise period measurement, this MCU delivers reliable low-frequency signal conditioning at very low unit cost.
推荐
LED Display and Signage Drivers
The PIC16C621T-20I/SO drives LED display matrices, seven-segment clusters and chase-light signage using its 13 I/O pins, hardware timer interrupts and 20 MHz clock. Software-driven Charlieplexing or multiplexed scanning is supported with deterministic timing, while the analog comparator monitors LED current via a shunt resistor for open/short detection. OTP memory locks the lighting pattern firmware so end customers cannot alter copyrighted animation sequences - valuable for commercial signage. Industrial temperature operation allows indoor and sheltered outdoor installation. The wide 18-SOIC footprint also provides robust mechanical attachment for vibration-prone LED panel assemblies.
推荐
Industrial Timer and Counter Modules
The PIC16C621T-20I/SO is widely used in industrial timer, counter and event-logging modules where its 16-bit Timer1 captures long intervals (up to several seconds at 20 MHz with prescaler) and its 8-bit Timer0 handles short-period control loops. The watchdog timer with dedicated RC oscillator protects against code lockup in unattended equipment, while brown-out reset ensures clean restarts on noisy 24 V industrial supply rails stepped down to 5 V. Industrial -40/+85 C operation and ICSP support simplify factory programming and field diagnostics. OTP memory makes the firmware immune to accidental erasure during ESD events common in industrial environments.
推荐
Simple Motor Control (DC and Stepper)
For small DC and bipolar stepper motor control loops, the PIC16C621T-20I/SO delivers enough compute to generate PWM drive signals, monitor back-EMF via the analog comparator, and sequence stepper windings without external logic. Its 13 I/O pins easily accommodate H-bridge enable inputs and quadrature encoder feedback. The 200 ns instruction cycle supports 10 kHz+ PWM rates with adequate resolution for hobby servo and small BLDC applications. OTP firmware locks proprietary acceleration profiles, a feature appreciated by OEM motor manufacturers. Industrial temperature range suits robotics and small-format automation cells.
推荐
Legacy Replacement of Discrete Logic
The PIC16C621T-20I/SO is often used to consolidate discrete 74HC logic gates, flip-flops and counter ICs into a single 18-SOIC chip, simplifying PCB layout and reducing BOM count in legacy products. Counters, shift registers, state machines and pulse generators can be implemented in software using the 13 I/O pins and 16-bit Timer1. Compared to discrete logic, the OTP MCU provides design secrecy - the firmware cannot be read back after programming, protecting intellectual property. Industrial -40/+85 C operation and ICSP programming support fast prototyping of legacy replacement boards that must remain form, fit and function compatible with existing hardware.
推荐
推荐产品汇总
工程参考数据： PIC16C621T-20I/SO ——对比、设计指导和合规信息。
选型指南
与替代料对比
| 参数 | 本产品 | PIC16C621T-20E/SO | PIC16C621AT-20I/SO | PIC16C621T-04I/SO | PIC16F628A-I/SO |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 18-SOIC (7.50 mm wide) | 18-SOIC (same) | 18-SOIC (same) | 18-SOIC (same) | 18-SOIC (same) |
| Max Clock Frequency | 20 MHz | 20 MHz | 20 MHz | 4 MHz | 20 MHz |
| Program Memory Type | OTP (1.75 KB) | OTP (1.75 KB) | OTP (1.75 KB) | OTP (1.75 KB) | Flash (3.5 KB) |
| Data RAM | 80 bytes | 80 bytes | 80 bytes | 80 bytes | 224 bytes |
| Operating Temperature | -40 C to +85 C (Industrial) | -40 C to +125 C (Extended) | -40 C to +85 C (Industrial) | -40 C to +85 C (Industrial) | -40 C to +85 C (Industrial) |
| Analog Comparator | Yes (1) | Yes (1) | Yes (1) | Yes (1) | Yes (2) |
| EEPROM | No | No | No | No | 128 bytes |
| USART | No | No | No | No | Yes |
| Pin Count | 18 | 18 | 18 | 18 | 18 |
关键差异点
- Higher speed grade than the 04 MHz variant （对比 PIC16C621T-04I/SO)
- Field-upgradeable flash memory with EEPROM and USART （对比 PIC16F628A-I/SO)
- Wider industrial temperature range than commercial grade （对比 PIC16C621T-04/SO)
- On-chip analog comparator for signal conditioning （对比 PIC16C620A-20I/SS)
设计说明
Decouple VDD (pin 14) with a 100 nF ceramic capacitor placed within 5 mm of the supply pin and a 10 uF bulk tantalum or aluminum capacitor near the package. The PIC16C621T-20I/SO can source/sink up to 25 mA per I/O pin (100 mA total), so relay coils and LED strings driven directly from the MCU need flyback diodes or current-limit resistors. Operating voltage must stay within 3.0-6.0 V; below 3.0 V the brown-out reset and bandgap reference are not guaranteed.
OTP memory cannot be erased - any firmware bug discovered after programming requires scrapping the part. Plan firmware revisions carefully or migrate to the flash-based PIC16F628A-I/SO pin-compatible alternative. During ICSP programming, ensure MCLR/VPP voltage rises to 13-14 V cleanly and RB6/RB7 are not loaded with heavy capacitance (keep below 50 pF) so the programmer can shift data reliably.
Route the oscillator traces (OSC1/OSC2, pins 16-15) as short as possible and keep them away from switching nodes such as relay drivers or PWM outputs to avoid injected clock noise. For crystals, place a grounded guard ring around the oscillator and load capacitors (typically 15-33 pF) within 5 mm of the pins. The 18-SOIC wide body (7.50 mm) provides better creepage than the narrow SOIC, beneficial for 5 V industrial designs.
The PIC16C621T-20I/SO dissipates approximately 50 mW at 20 MHz with 5 V supply and 13 active I/O pins - well within the 18-SOIC thermal envelope. However, if all 13 I/O pins drive 20 mA continuous loads (total 260 mA), package self-heating can raise junction temperature by 15-20 C. For high-current sink applications, use external driver ICs (e.g., ULN2003) instead of direct pin loading to keep junction rise below 10 C.
合规信息
RoHS compliance not stated in verified web data; PIC16C series is generally lead-free per Microchip product family. AEC-Q100 not applicable - this is an 8-bit OTP MCU for industrial/consumer use. For automotive applications, refer to Microchip's PIC16F6xx AEC-Q100 qualified variants.