PIC16C77T-20I/PQ - 14KB OTP 8-bit MCU, 20MHz | Microchip
MPN: PIC16C77T-20I/PQ ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $12.5 | $12.50 |
| 10 | $11.25 | $112.50 |
| 100 | $9.85 | $985.00 |
| 500 | $8.75 | $4,375.00 |
| 1,000 | $7.95 | $7,950.00 |
PIC16C77T-20I/PQ Overview
A microcontroller (MCU) is a single-chip computer containing a CPU, memory (program + data), and programmable I/O peripherals. The PIC16C7X family belongs to Microchip's mid-range PIC architecture, sitting between the baseline PIC16C5X and the enhanced PIC16C9X/PIC17C families. This 8-bit RISC core executes most instructions in a single cycle, providing deterministic timing that is critical for real-time control loops, while the 14-bit instruction word balances code density against register width for embedded control workloads.
Key features include Harvard architecture with separate program and data buses, 33 digital I/O pins, three timer/counter modules, two Capture/Compare/PWM (CCP) peripherals, a USART with addressable RS-485 mode, and the previously mentioned 8-bit ADC. The 'I' suffix denotes the industrial temperature grade, while '20' indicates the 20 MHz speed option and 'T' denotes tape-and-reel packaging; the /PQ package code corresponds to a 44-pin Metric Quad Flat Pack (MQFP) windowed body.
The OTP EPROM program memory supports prototyping and low-volume production, while 368 bytes of data RAM and 256 bytes of EEPROM (typical for this family) provide working storage for variables and non-volatile parameters. The integrated ADC and rich peripheral set allow the PIC16C77T-20I/PQ to replace multiple discrete components in a system.
Typical applications include industrial process control, motor control front-ends, instrumentation, automotive sensor interface modules, and embedded control boards where an integrated ADC reduces BOM cost. The wide operating voltage and industrial temperature grade also suit factory automation nodes.
Designers should plan for in-circuit serial programming (ICSP) and reserve a quartz crystal or resonator footprint for clock stability, since timing accuracy drives both UART baud-rate integrity and ADC conversion precision. Note that 'PQ' denotes MQFP windowed ceramic packaging, which is unusual for industrial runs; verify your assembly process supports this package before scaling production.
This page synthesizes distributor pricing, drop-in same-package alternatives, and design guidance that goes beyond the manufacturer datasheet to help engineers select and second-source the PIC16C77T-20I/PQ.
Drop-in alternatives for PIC16C77T-20I/PQ — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C77T-20I/L
✅ Drop-In✓ In Stock
$6.2 / Unit
View Datasheet →PIC16C77T-20/PQ
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C77T-10I/PQ
✅ Drop-In✓ In Stock
$8.9 / Unit
View Datasheet →PIC16C77T-04I/PQ
✅ Drop-In✓ In Stock
$12.1 / Unit
View Datasheet →PIC16C67T-20I/PQ
✅ Drop-In✓ In Stock
$4.41 / Unit
View Datasheet →PIC16F877-20I/PQ
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C77T-20I/PQ Maximum Ratings & Electrical Characteristics
| Core Architecture | 8-bit PIC16C mid-range RISC |
| Program Memory | 14 KB (8K x 14) OTP EPROM |
| Data RAM | 368 bytes |
| Maximum Clock Speed | 20 MHz |
| Supply Voltage | 4.0 V to 5.5 V |
| I/O Pins | 33 |
| ADC | 8-channel, 8-bit on-chip |
| Timers | 3 (Timer0, Timer1, Timer2) |
| CCP Modules | 2 (Capture/Compare/PWM) |
| Serial Interface | USART (addressable RS-485) |
| Operating Temperature | -40C to +85C (industrial grade, 'I') |
| Package | 44-MQFP (PQ), 10x10 mm, tape and reel ('T' suffix) |
| Package Type | Windowed ceramic, MQFP |
| Mounting Type | Surface Mount |
| Instruction Set | PIC16C mid-range, 14-bit instructions |
PIC16C77T-20I/PQ Pin Configuration
| Pin 1 | RA0/AN0 — PORTA bit 0 / analog input channel 0 |
| Pin 2 | RA1/AN1 — PORTA bit 1 / analog input channel 1 |
| Pin 3 | RA2/AN2 — PORTA bit 2 / analog input channel 2 |
| Pin 4 | RA3/AN3/VREF — PORTA bit 3 / analog input channel 3 / ADC voltage reference |
| Pin 5 | RA4/T0CKI — PORTA bit 4 / Timer0 clock input |
| Pin 6 | RA5/AN4/SS — PORTA bit 5 / analog input channel 4 / SPI slave select |
| Pin 7 | OSC1/CLKIN — Oscillator crystal input / external clock input |
| Pin 8 | OSC2/CLKOUT — Oscillator crystal output / clock output (FOSC/4) |
| Pin 9 | MCLR — Master clear reset (active low) / programming voltage input |
| Pin 10 | VSS — Ground reference |
| Pin 11 | VDD — Positive supply (4.0-5.5 V) |
| Pin 12 | RB0/INT — PORTB bit 0 / external interrupt input |
| Pin 13 | RB1 — PORTB bit 1 |
| Pin 14 | RB2 — PORTB bit 2 |
| Pin 15 | RB3/PGM — PORTB bit 3 / low-voltage programming input |
| Pin 16 | RB4 — PORTB bit 4 (interrupt-on-change) |
| Pin 17 | RB5 — PORTB bit 5 (interrupt-on-change) |
| Pin 18 | RB6/PGC — PORTB bit 6 / ICSP clock (interrupt-on-change) |
| Pin 19 | RB7/PGD — PORTB bit 7 / ICSP data (interrupt-on-change) |
| Pin 20 | VSS — Ground reference |
| Pin 21 | VDD — Positive supply (4.0-5.5 V) |
| Pin 22 | RC0/T1OSO/T1CKI — PORTC bit 0 / Timer1 oscillator output / Timer1 clock input |
| Pin 23 | RC1/T1OSI/CCP2 — PORTC bit 1 / Timer1 oscillator input / CCP2 I/O |
| Pin 24 | RC2/CCP1 — PORTC bit 2 / CCP1 I/O (PWM output) |
| Pin 25 | RC3/SCK/SCL — PORTC bit 3 / SPI clock / I2C clock |
| Pin 26 | RC4/SDI/SDA — PORTC bit 4 / SPI data in / I2C data |
| Pin 27 | RC5/SDO — PORTC bit 5 / SPI data out |
| Pin 28 | RC6/TX/CK — PORTC bit 6 / USART transmit / USART clock |
| Pin 29 | RC7/RX/DT — PORTC bit 7 / USART receive / USART data |
| Pin 30 | VSS — Ground reference |
| Pin 31 | VDD — Positive supply (4.0-5.5 V) |
| Pin 32 | RD0/PSP0 — PORTD bit 0 / parallel slave port bit 0 |
| Pin 33 | RD1/PSP1 — PORTD bit 1 / parallel slave port bit 1 |
| Pin 34 | RD2/PSP2 — PORTD bit 2 / parallel slave port bit 2 |
| Pin 35 | RD3/PSP3 — PORTD bit 3 / parallel slave port bit 3 |
| Pin 36 | RD4/PSP4 — PORTD bit 4 / parallel slave port bit 4 |
| Pin 37 | RD5/PSP5 — PORTD bit 5 / parallel slave port bit 5 |
| Pin 38 | RD6/PSP6 — PORTD bit 6 / parallel slave port bit 6 |
| Pin 39 | RD7/PSP7 — PORTD bit 7 / parallel slave port bit 7 |
| Pin 40 | VSS — Ground reference |
| Pin 41 | VDD — Positive supply (4.0-5.5 V) |
| Pin 42 | RE0/RD/AN5 — PORTE bit 0 / read control for PSP / analog input channel 5 |
| Pin 43 | RE1/WR/AN6 — PORTE bit 1 / write control for PSP / analog input channel 6 |
| Pin 44 | RE2/CS/AN7 — PORTE bit 2 / chip select for PSP / analog input channel 7 |
Typical Applications
PIC16C77T-20I/PQ is suitable for 6 applications: Industrial Process Control, Motor Control Front-End, Instrumentation and Data Acquisition, Automotive Sensor Interface Modules, Embedded Control Boards, HVAC and Building Automation.
Industrial Process Control
The PIC16C77T-20I/PQ is well suited to industrial process-control nodes because its 8-channel 8-bit ADC integrates transducer signal acquisition, while 33 I/O pins drive valves, relays, and indicator LEDs. Operating from 4.0-5.5 V at 20 MHz, it executes one instruction every 200 ns - enough to run PID loops at sub-millisecond intervals. The industrial -40C to +85C temperature grade handles unconditioned factory-floor environments, and the OTP memory holds firmware securely without external storage. Place 100 nF decoupling caps on every VDD/VSS pair, with a 10 uF bulk at the regulator output, and add a watchdog timer (WDT) reset in firmware for unattended deployments.
Recommended
Motor Control Front-End
For brushed DC and stepper motor front-ends, the PIC16C77T-20I/PQ delivers the timing precision needed for PWM generation through its two CCP modules and the high-speed 16-bit Timer1. The 20 MHz clock drives PWM frequencies above 40 kHz (above audible band) while leaving CPU headroom for commutation logic. The 8-bit ADC samples back-EMF or current-sense signals up to 8 channels, allowing single-chip BLDC trapezoidal commutation. Industrial-grade temperature rating supports under-hood and motor-housing placement. Add TVS diodes on H-bridge FET gates and a current-sense amplifier front-end to the ADC channel for closed-loop torque control.
Recommended
Instrumentation and Data Acquisition
The PIC16C77T-20I/PQ's integrated 8-bit ADC, 33 I/O, and USART make it a competent standalone data-acquisition front-end for laboratory and field instrumentation. Channelized analog inputs feed sensors (temperature bridges, strain gauges, pH probes), while the USART streams digitized samples to a host PC or display controller at standard baud rates. The 14 KB OTP holds calibration tables and linearization routines. Industrial temperature rating supports outdoor or refrigerated deployments. Use a precision 5 V reference (e.g., MCP1541) for ADC accuracy rather than VDD, and include a low-pass RC on each analog input to suppress RF pickup.
Recommended
Automotive Sensor Interface Modules
Although not AEC-Q100 qualified, the PIC16C77T-20I/PQ is frequently deployed in non-safety automotive modules such as body controllers, sensor clusters, and lighting drivers. The 8-channel 8-bit ADC reads multiple analog sensors simultaneously, and the USART interfaces to body-network transceivers. The industrial -40C to +85C grade covers cabin and most under-hood environments; for harsher locations, add a thermally conductive PCB pad. OTP memory protects firmware against unauthorized reflashing - a security benefit over flash. Always add reverse-battery protection (Schottky diode in series with VDD) and load-dump TVS for automotive robustness.
Recommended
Embedded Control Boards
For embedded control boards that integrate analog sensing, digital I/O, and serial communication on a single chip, the PIC16C77T-20I/PQ is a proven workhorse. Its 8-bit PIC mid-range core is widely supported by the MPLAB X IDE and the free XC8 compiler, lowering development cost. The 368 bytes of RAM and 14 KB OTP are adequate for state machines, menu handlers, and simple protocol stacks. The USART supports RS-232, RS-485, and LIN bus physical layers. Industrial temperature and the MQFP package suit compact SMD assemblies. Reserve the MCLR pin for ICSP programming during prototype bring-up.
Recommended
HVAC and Building Automation
The PIC16C77T-20I/PQ's ADC-rich, multi-timer architecture suits HVAC zone controllers, damper actuators, and building-automation nodes that read temperature, humidity, and pressure sensors while driving relays and triacs. The 33 I/O pins accommodate multiple zone outputs and keypad/display interfaces, while the USART links to a central building-management system. Industrial temperature rating supports unconditioned mechanical rooms. The OTP memory prevents accidental firmware tampering by field technicians - a regulatory plus for commercial HVAC. Add a zero-crossing detector on an external interrupt pin for synchronous triac firing and EMI reduction.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C77T-20I/PQ — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C77T-20I/L | PIC16C77T-20/PQ | PIC16C77T-10I/PQ | PIC16C67T-20I/PQ | PIC16F877-20I/PQ |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 44-MQFP (PQ) | 44-MQFP (PQ) - same | 44-MQFP (PQ) - same | 44-MQFP (PQ) - same | 44-MQFP (PQ) - same | 44-MQFP (PQ) - same |
| Program Memory | 14 KB OTP | 14 KB OTP | 14 KB OTP | 14 KB OTP | 8 KB OTP | 14 KB Flash |
| Maximum Clock Speed | 20 MHz | 20 MHz | 20 MHz | 10 MHz | 20 MHz | 20 MHz |
| Temperature Grade | Industrial -40C to +85C | Industrial -40C to +85C | Commercial 0C to +70C | Industrial -40C to +85C | Industrial -40C to +85C | Industrial -40C to +85C |
| Memory Type | OTP EPROM | OTP EPROM | OTP EPROM | OTP EPROM | OTP EPROM | Flash |
| ADC | 8-ch 8-bit | 8-ch 8-bit | 8-ch 8-bit | 8-ch 8-bit | 8-ch 8-bit | 8-ch 10-bit |
| I/O Pins | 33 | 33 | 33 | 33 | 33 | 33 |
| Supply Voltage | 4.0 V to 5.5 V | 4.0 V to 5.5 V | 4.0 V to 5.5 V | 4.0 V to 5.5 V | 4.0 V to 5.5 V | 4.0 V to 5.5 V |
Key Differentiators
- Industrial temperature grade in windowed MQFP package (vs PIC16C77T-20/PQ)
- Maximum 20 MHz clock for tight real-time control loops (vs PIC16C77T-10I/PQ)
- 14 KB OTP program memory for larger firmware (vs PIC16C67T-20I/PQ)
- OTP EPROM security prevents unauthorized reflashing (vs PIC16F877-20I/PQ)
Design Notes
Estimated: at VDD=5.0 V, 20 MHz clock and typical 8 mA active supply current (per PIC16C7X family datasheet), the PIC16C77T-20I/PQ consumes ~40 mW active and ~50 uW in sleep. Place a 100 nF ceramic decoupling cap within 5 mm of every VDD/VSS pair (the MQFP exposes pins 11/20, 21/30, 31/40, 41 with their respective VSS returns) and a single 10 uF bulk tantalum or ceramic at the regulator output. The windowed ceramic package handles inrush current better than plastic but is more thermally massive - allow extra cool-down time before rework.
Route the quartz crystal or resonator traces (OSC1/OSC2, pins 7/8) as short as possible (under 10 mm) and guard them with a ground pour on both sides of the trace. Keep ADC analog traces (PORTA, PORTE) away from digital switching lines (PORTD parallel slave port) to avoid digital-to-analog crosstalk. The MQFP-44 lead pitch is 0.8 mm - use 0.4 mm-wide traces and 0.2 mm clearance per IPC-7351. Place a ground ring around the entire IC for thermal spreading and EMI shielding.
Do not confuse the 'PQ' suffix (MQFP windowed ceramic tape-and-reel) with 'PT' (TQFP plastic) or 'P' (PDIP plastic) - they share the 44-pin count but have different footprints. The windowed ceramic body is NOT RoHS compliant by default; verify lead-free status on Microchip's product page if RoHS is required. Also note that OTP EPROM cannot be erased by software - only the quartz window allows UV erasure, so plan for windowed units during development and non-windowed (-04/PQ non-I variant) for production.
Compliance Information
The 'PQ' suffix denotes MQFP windowed ceramic package, which historically contains lead in the ceramic-glass frit and pin plating - typically NOT RoHS compliant. Not AEC-Q100 qualified. For RoHS-compliant designs in the same family, migrate to PIC16F877A-I/PT (TQFP-44, plastic, lead-free).
