PIC16C64AT-04I/L - 4MHz 8-bit OTP MCU 3.5KB | Microchip PLCC-44
MPN: PIC16C64AT-04I/L ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $9.5 | $9.50 |
| 10 | $8.55 | $85.50 |
| 100 | $7.6 | $760.00 |
| 500 | $6.84 | $3,420.00 |
| 1,000 | $6.08 | $6,080.00 |
PIC16C64AT-04I/L Overview
An 8-bit microcontroller (MCU) is a programmable integrated circuit that combines a CPU, RAM, program memory, and peripherals on a single die. MCUs are classified by bit-width, memory type, and architectural family; the PIC16CXX belongs to the classic PIC mid-range family, a Harvard RISC architecture that emphasizes deterministic instruction timing, low power, and a compact 35-instruction instruction set. The OTP memory flavor means the part is programmed once and is typically used in production runs where firmware is finalized and stable.
Key features include a high-performance RISC CPU with only 35 single-word instructions to learn, DC to 4MHz clock input, 33 I/O pins with individual direction control, programmable code protection, power-on reset, watchdog timer with on-chip RC oscillator, and an industrial temperature range of -40C to +85C. The device also integrates a 14-bit instruction word with 8-bit data path, hardware stack, and multiple timer/counter modules suitable for embedded control tasks.
The PIC16C64A architecture uses a modified Harvard design with separate program and data buses, allowing instruction fetch and operand read to occur in the same cycle. The OTP EPROM cell enables windowed programming for prototyping with UV erasure, while the industrial-grade ceramic windowed CDIP variant exists for development and engineering samples. The PLCC-44 footprint is well-suited for socketed programming and rework in legacy industrial designs.
Typical applications include industrial automation controllers, HVAC fan and pump controls, appliance control boards, security and access control panels, and automotive body electronics (non-safety). The 33 I/O count and 128-byte RAM make it suitable for keypad scanning, LED or relay driving, and UART-based communication in mid-complexity embedded designs.
When designing with this part, ensure the 4V-5.5V supply is well regulated, leave unused I/O pins configured as outputs and tied low to minimize current consumption, and use the watchdog timer for reliable recovery from software lockups. The OTP memory cannot be reprogrammed in-circuit; a Flash-based PIC16F equivalent is recommended for prototypes requiring iterative firmware updates.
This page synthesizes distributor pricing, drop-in alternatives in the same PLCC-44 footprint, and practical design notes that go beyond the manufacturer datasheet.
Drop-in alternatives for PIC16C64AT-04I/L — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with PIC16C64AT-04I/L (same form factor and footprint) — differing in Mounting Type, Core Architecture, Watchdog Timer, Instruction Set, Package.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C64A-04I/L
✅ Drop-In✓ In Stock
$4.5 / Unit
View Datasheet →PIC16C64AT-04I/PQ
✅ Drop-In✓ In Stock
$7.55 / Unit
View Datasheet →PIC16C64A-10I/L
✅ Drop-In✓ In Stock
$3.45 / Unit
View Datasheet →PIC16C64A-20I/L
✅ Drop-In✓ In Stock
$3.1 / Unit
View Datasheet →PIC16F877A-I/L
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C64AT-04I/L Maximum Ratings & Electrical Characteristics
| Product Family | PIC16C Microcontroller |
| Core Architecture | 8-bit RISC (Harvard) |
| Program Memory Size | 3.5 KB (2K x 14) OTP |
| RAM Size | 128 bytes |
| Maximum Clock Frequency | 4 MHz |
| Supply Voltage Range | 4 V to 5.5 V |
| Number of I/O Pins | 33 |
| Instruction Set Size | 35 instructions (single word) |
| Instruction Word Width | 14 bits |
| Data Path Width | 8 bits |
| Operating Temperature Range | -40 C to +85 C (Industrial) |
| Package Type | 44-pin PLCC |
| Package Dimensions | 16.59 x 16.59 mm |
| Mounting Type | Surface Mount (J-Lead) |
| Watchdog Timer | Yes (on-chip RC oscillator) |
| Power-On Reset | Yes |
PIC16C64AT-04I/L Pin Configuration
| Pin 1 | MCLR/VPP — Master Clear (Reset) input / Programming voltage |
| Pin 2 | RA0/AN0 — PORTA bit 0 / Analog input 0 |
| Pin 3 | RA1/AN1 — PORTA bit 1 / Analog input 1 |
| Pin 4 | RA2/AN2 — PORTA bit 2 / Analog input 2 |
| Pin 5 | RA3/AN3/VREF — PORTA bit 3 / Analog input 3 / Voltage reference |
| Pin 6 | RA4/T0CKI — PORTA bit 4 / Timer 0 clock input |
| Pin 7 | RA5/SS/AN4 — PORTA bit 5 / Slave Select / Analog input 4 |
| Pin 8 | RE0/RD/AN5 — PORTE bit 0 / Read control / Analog input 5 |
| Pin 9 | RE1/WR/AN6 — PORTE bit 1 / Write control / Analog input 6 |
| Pin 10 | RE2/CS/AN7 — PORTE bit 2 / Chip Select / Analog input 7 |
| Pin 11 | VDD — Positive supply voltage |
| Pin 12 | VSS — Ground reference |
| Pin 13 | OSC1/CLKIN — Oscillator input / External clock input |
| Pin 14 | OSC2/CLKOUT — Oscillator output / Clock output |
| Pin 15 | RC0/T1OSO/T1CKI — PORTC bit 0 / Timer1 oscillator output / Timer1 clock |
| Pin 16 | RC1/T1OSI/CCP2 — PORTC bit 1 / Timer1 oscillator input / CCP2 |
| Pin 17 | RC2/CCP1 — PORTC bit 2 / Capture/Compare/PWM 1 |
| Pin 18 | RC3/SCK/SCL — PORTC bit 3 / SPI clock / I2C clock |
| Pin 19 | RD0/PSP0 — PORTD bit 0 / Parallel Slave Port bit 0 |
| Pin 20 | RD1/PSP1 — PORTD bit 1 / Parallel Slave Port bit 1 |
| Pin 21 | RD2/PSP2 — PORTD bit 2 / Parallel Slave Port bit 2 |
| Pin 22 | RD3/PSP3 — PORTD bit 3 / Parallel Slave Port bit 3 |
| Pin 23 | RC4/SDI/SDA — PORTC bit 4 / SPI data in / I2C data |
| Pin 24 | RC5/SDO — PORTC bit 5 / SPI data out |
| Pin 25 | RC6/TX/CK — PORTC bit 6 / UART TX / Clock |
| Pin 26 | RC7/RX/DT — PORTC bit 7 / UART RX / Data |
| Pin 27 | RD4/PSP4 — PORTD bit 4 / Parallel Slave Port bit 4 |
| Pin 28 | RD5/PSP5 — PORTD bit 5 / Parallel Slave Port bit 5 |
| Pin 29 | RD6/PSP6 — PORTD bit 6 / Parallel Slave Port bit 6 |
| Pin 30 | RD7/PSP7 — PORTD bit 7 / Parallel Slave Port bit 7 |
| Pin 31 | VSS — Ground reference |
| Pin 32 | VDD — Positive supply voltage |
| Pin 33 | RB0/INT — PORTB bit 0 / External interrupt |
| Pin 34 | RB1 — PORTB bit 1 |
| Pin 35 | RB2 — PORTB bit 2 |
| Pin 36 | RB3 — PORTB bit 3 |
| Pin 37 | RB4 — PORTB bit 4 |
| Pin 38 | RB5 — PORTB bit 5 |
| Pin 39 | RB6/PGC — PORTB bit 6 / ICSP clock |
| Pin 40 | RB7/PGD — PORTB bit 7 / ICSP data |
| Pin 41 | NC — Not connected |
| Pin 42 | NC — Not connected |
| Pin 43 | NC — Not connected |
| Pin 44 | NC — Not connected |
Typical Applications
PIC16C64AT-04I/L is suitable for 6 applications: Industrial Automation Controllers, HVAC Fan and Pump Controls, Appliance Control Boards, Security and Access Control Panels, Automotive Body Electronics (Non-Safety), Test and Measurement Instruments.
Industrial Automation Controllers
The PIC16C64AT-04I/L fits industrial automation controllers with its 33 I/O pins capable of driving relays, sensors, and HMI keypads. The 128-byte RAM handles state machine variables, while the 4MHz clock supports UART communication at standard baud rates up to 38.4 kbps. Hardware watchdog timer recovers from software faults in motor and valve control applications, critical for unattended machinery. The -40C to +85C industrial temperature range tolerates factory floor environments, and the OTP memory suits mature firmware designs deployed in high-volume production lines.
Recommended
HVAC Fan and Pump Controls
The PIC16C64AT-04I/L is well suited for HVAC fan and pump control boards where 33 I/O pins can interface with temperature sensors, triac drivers, and LED status indicators. The 14-bit instruction set provides efficient PID loop implementation for closed-loop fan speed and pressure regulation. Operating from a regulated 5V supply, the device's low CMOS power consumption keeps standby current minimal for energy-efficient appliance designs. Industrial temperature grade ensures reliable operation in unconditioned plant rooms.
Recommended
Appliance Control Boards
The PIC16C64AT-04I/L integrates washing machine, dishwasher, and microwave oven control functions with its OTP memory locking in production firmware permanently. The Harvard RISC architecture provides deterministic interrupt response for time-critical sequencing of motor drivers, valves, and heating elements. Power-on reset and watchdog timer prevent lockups in white goods appliances, while the 33 I/O pins accommodate matrix keypads, seven-segment displays, and buzzer drivers. Surface-mount PLCC-44 packaging supports automated assembly.
Recommended
Security and Access Control Panels
The PIC16C64AT-04I/L addresses keypad readers, door controllers, and intrusion alarm panels requiring stable OTP firmware preventing field tampering. The 128-byte RAM stores user credential buffers and event logs in real time, while the 33 I/O pins scan 4x4 keypads, drive piezoelectric buzzers, and read magnetic reed switches. UART peripherals support communication with central alarm panels at standard baud rates. Industrial temperature operation tolerates outdoor cabinet environments.
Recommended
Automotive Body Electronics (Non-Safety)
The PIC16C64AT-04I/L serves non-safety automotive body control modules such as seat controllers, mirror adjusters, and ambient lighting systems. The 5V operation interfaces directly with automotive 12V bus via regulator, while the -40C to +85C industrial temperature range covers cabin environments. The watchdog timer and power-on reset handle automotive voltage transients and cranking conditions. OTP memory locks firmware at production, ensuring field reliability across vehicle service life.
Recommended
Test and Measurement Instruments
The PIC16C64AT-04I/L drives handheld multimeters, cable testers, and bench-top instrumentation requiring deterministic real-time control. The 35-instruction RISC set implements measurement state machines efficiently, while the 33 I/O pins drive LCD segments, button inputs, and range selection relays. The 4MHz clock generates precise timing references for frequency counters and capacitance meters. OTP memory locks calibrated firmware preventing unauthorized recalibration in field-deployed instruments.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C64AT-04I/L — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C64A-04I/L | PIC16C64AT-04I/PQ | PIC16C64A-10I/L | PIC16C64A-20I/L | PIC16F877A-I/L |
|---|---|---|---|---|---|---|
| Package | PLCC-44 | PLCC-44 (same) | MQFP-44 (same pin count) | PLCC-44 (same) | PLCC-44 (same) | PLCC-44 (same) |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Max Clock Frequency | 4 MHz | 4 MHz | 4 MHz | 10 MHz | 20 MHz | 20 MHz |
| Program Memory | 3.5 KB OTP | 3.5 KB OTP | 3.5 KB OTP | 3.5 KB OTP | 3.5 KB OTP | 14 KB Flash |
| RAM Size | 128 bytes | 128 bytes | 128 bytes | 128 bytes | 128 bytes | 368 bytes |
| Number of I/O Pins | 33 | 33 | 33 | 33 | 33 | 33 |
| Memory Type | OTP EPROM | OTP EPROM | OTP EPROM | OTP EPROM | OTP EPROM | Flash |
| Operating Temperature | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C |
Key Differentiators
- Tape and reel packaging for SMT automation (vs PIC16C64A-04I/L)
- Higher 10 MHz clock speed option available (vs PIC16C64A-10I/L)
- Flash reprogrammability for iterative development (vs PIC16F877A-I/L)
Design Notes
Power the PIC16C64AT-04I/L from a regulated 5V rail with both VDD pins (11 and 32) connected and both VSS pins (12 and 31) grounded. Place a 100 nF decoupling capacitor within 5 mm of each VDD pin and a 10 uF bulk capacitor near the IC. Power-on reset is internal but the MCLR pin (pin 1) should be pulled high through a 10 kohm resistor to VDD with optional 100 nF to ground for noise immunity. Supply voltage must remain within 4.0V to 5.5V; brownout below 4V can cause EPROM read errors.
OTP memory cannot be reprogrammed: any firmware bug in production becomes permanent. Always validate firmware thoroughly on a windowed PIC16C64A/JW prototype or Flash PIC16F877A-I/L equivalent before committing to OTP programming. Configure unused I/O pins as outputs and tie them low to minimize current consumption. The watchdog timer should be enabled in critical applications and periodically cleared via CLRWDT to reset the MCU on software faults.
Route the crystal traces (OSC1/OSC2, pins 13-14) as short as possible and keep them away from high-current switching traces to prevent clock corruption. For 4 MHz operation, use a 4 MHz crystal with 22 pF load capacitors to ground on each oscillator pin. Place the PLCC-44 socket footprint on the PCB so that pin 1 is identifiable via chamfered corner marking; include a decoupling capacitor land pattern under the socket if board area permits for improved EMI performance.
Compliance Information
RoHS and lead-free status not explicitly stated in the verified web data for PIC16C64AT-04I/L. Industrial temperature grade (-40C to +85C) is qualified but not AEC-Q100 automotive. Legacy OTP parts often predate RoHS transition; confirm compliance with distributor before environmental-sensitive designs.
