PIC16C64AT-04/L - 8-Bit OTP MCU, 4MHz, 3.5KB EPROM, 44-PLCC | Microchip
MPN: PIC16C64AT-04/L ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $12.5 | $12.50 |
| 10 | $11.2 | $112.00 |
| 100 | $9.85 | $985.00 |
| 500 | $8.95 | $4,475.00 |
| 1,000 | $8.1 | $8,100.00 |
PIC16C64AT-04/L Overview
A microcontroller (MCU) is a single-chip computer that integrates a CPU, memory (program + data), and programmable I/O peripherals on one die. The PIC16C family uses a Harvard RISC architecture with a 14-bit instruction word and an 8-bit data path, belonging to the broader hierarchy of microcontroller -> embedded processor -> semiconductor device. PIC MCUs are widely used for low-power, deterministic control tasks where simple peripherals and predictable interrupt response are more important than raw compute throughput.
Key features of the PIC16C64AT-04/L include its OTP EPROM program memory (3.5KB), 33 digital I/O lines, a 5V nominal operating supply, an integrated 8-bit timer/counter, and a Watchdog Timer for safe operation. The "04" speed grade specifies a 4MHz maximum oscillator frequency, while the "T" suffix denotes the Tape & Reel packaging variant and "L" denotes the PLCC package. The EPROM-based memory means this part is intended for production programming only, not field re-programmability.
Architecturally, the device uses a single-accumulator RISC core with a two-stage pipeline and 35 single-word instructions, most of which execute in a single instruction cycle (250 ns at 4MHz). The 14-bit instruction width allows a large opcode space relative to its 8-bit data bus, and the Harvard separation of program and data buses eliminates fetch-decode conflicts, yielding deterministic throughput. The on-chip peripherals are mapped into a small register file accessible through banked addressing.
Typical applications for the PIC16C64AT-04/L include industrial control logic, automotive body electronics (non-safety subsystems), appliance controllers, sensor interface boards, and simple human-machine interface (HMI) panels that need deterministic real-time response. The 44-pin PLCC package also gives engineers a socketable footprint for prototyping and low-volume assembly, which simplifies device replacement during board bring-up.
When designing with this part, note that OTP memory cannot be erased or rewritten - firmware must be fully validated before programming. The 4MHz speed grade limits instruction throughput to roughly 4 MIPS, so compute-intensive algorithms must be offloaded or written efficiently. For new designs, Microchip recommends the flash-based PIC16F series as the modern equivalent with in-circuit programmability.
Drop-in alternatives for PIC16C64AT-04/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-04/L (same form factor and footprint) — differing in Program Memory Type, Package, Mounting Type, RAM Size, Communication.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C64A-04/L
✅ Drop-In✓ In Stock
$6.2 / Unit
View Datasheet →PIC16C64A-04I/L
✅ Drop-In✓ In Stock
$4.5 / Unit
View Datasheet →PIC16C64A-10/L
✅ Drop-In✓ In Stock
$5.5 / Unit
View Datasheet →PIC16C64A-04E/L
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16F877A-I/L
✅ Drop-In ⚠️ 参数待验证📋 Reference alternative (not in catalog)
PIC16C64AT-04/L Maximum Ratings & Electrical Characteristics
| Core Architecture | 8-bit PIC RISC (Harvard) |
| Family | PIC16C (PIC16C64A series) |
| Program Memory Type | OTP EPROM |
| Program Memory Size | 3.5 KB (2K x 14) |
| RAM Size | 128 x 8 bytes |
| Maximum Clock Frequency | 4 MHz |
| Instruction Cycle Time | 1 us (at 4 MHz) |
| Data Bus Width | 8 bit |
| Instruction Word Width | 14 bit |
| Supply Voltage | 5 V nominal |
| I/O Pins | 33 |
| Package Type | 44-pin PLCC (J-Lead, 16.59 x 16.59 mm) |
| Mounting Type | Surface Mount |
| Operating Temperature Grade | Commercial |
| Packaging | Tape & Reel |
PIC16C64AT-04/L Pin Configuration
| Pin 1 | RA0/AN0 — Port A bit 0 / Analog input 0 (digital I/O on this part - no ADC) |
| Pin 2 | RA1/AN1 — Port A bit 1 / Analog input 1 (digital I/O on this part) |
| Pin 3 | RA2/AN2 — Port A bit 2 (digital I/O) |
| Pin 4 | RA3/AN3 — Port A bit 3 (digital I/O) |
| Pin 5 | RA4/T0CKI — Port A bit 4 / Timer0 clock input |
| Pin 6 | RA5/SS — Port A bit 5 / SPI slave select |
| Pin 7 | RE0/RD — Port E bit 0 / Read strobe for parallel slave port |
| Pin 8 | RE1/WR — Port E bit 1 / Write strobe for parallel slave port |
| Pin 9 | RE2/CS — Port E bit 2 / Chip select for parallel slave port |
| Pin 10 | VDD — Positive supply voltage (5V nominal) |
| Pin 11 | VSS — Ground reference |
| Pin 12 | OSC1/CLKIN — Oscillator input / external clock input |
| Pin 13 | OSC2/CLKOUT — Oscillator output / clock out |
| Pin 14 | T1CKI — Timer1 clock input |
| Pin 15 | RC0 — Port C bit 0 |
| Pin 16 | RC1 — Port C bit 1 |
| Pin 17 | RC2 — Port C bit 2 |
| Pin 18 | RC3 — Port C bit 3 |
| Pin 19 | RD0 — Port D bit 0 |
| Pin 20 | RD1 — Port D bit 1 |
| Pin 21 | RD2 — Port D bit 2 |
| Pin 22 | RD3 — Port D bit 3 |
| Pin 23 | RC4 — Port C bit 4 |
| Pin 24 | RC5 — Port C bit 5 |
| Pin 25 | RC6 — Port C bit 6 |
| Pin 26 | RC7 — Port C bit 7 |
| Pin 27 | RD4 — Port D bit 4 |
| Pin 28 | RD5 — Port D bit 5 |
| Pin 29 | RD6 — Port D bit 6 |
| Pin 30 | RD7 — Port D bit 7 |
| Pin 31 | VSS — Ground reference |
| Pin 32 | VDD — Positive supply voltage (5V nominal) |
| Pin 33 | RB0/INT — Port B bit 0 / External interrupt input |
| Pin 34 | RB1 — Port B bit 1 |
| Pin 35 | RB2 — Port B bit 2 |
| Pin 36 | RB3 — Port B bit 3 |
| Pin 37 | RB4 — Port B bit 4 |
| Pin 38 | RB5 — Port B bit 5 |
| Pin 39 | RB6 — Port B bit 6 |
| Pin 40 | RB7 — Port B bit 7 |
| Pin 41 | MCLR/VPP — Master clear reset (active low) / programming voltage input |
| Pin 42 | NC — Not connected (per datasheet, reserved) |
| Pin 43 | NC — Not connected (per datasheet, reserved) |
| Pin 44 | NC — Not connected (per datasheet, reserved) |
Typical Applications
PIC16C64AT-04/L is suitable for 6 applications: Industrial Control Logic, Appliance Control Boards, Automotive Body Electronics, Sensor Interface Boards, Human-Machine Interface (HMI) Panels, Prototyping and Educational Development.
Industrial Control Logic
The PIC16C64AT-04/L fits industrial control logic applications thanks to its deterministic 8-bit RISC core and 4MHz clock producing 250ns instruction cycles. With 33 digital I/O lines, it can directly interface sensors, relay coils, contactors, and indicator LEDs without external logic. The 3.5KB OTP EPROM holds substantial state-machine firmware, while the integrated Watchdog Timer recovers the system from software lockups in noisy factory environments.
Recommended
Appliance Control Boards
Washing machines, microwave ovens, and HVAC controllers benefit from the PIC16C64AT-04/L's 33 I/O pins which interface keypad matrix, seven-segment LEDs, TRIAC optos, and temperature sensors without external glue logic. The 4MHz clock provides adequate throughput for scan loops, while the 128-byte RAM buffers user inputs and timer state. The commercial temperature grade fits indoor appliance enclosures where ambient stays within 0-70C.
Recommended
Automotive Body Electronics
Non-safety body modules such as seat controllers, mirror adjusters, and interior lighting can use the PIC16C64AT-04/L with the industrial-grade variant. The Harvard RISC architecture gives deterministic interrupt latency which matters when responding to CAN bus messages or PWM dimming updates. The 3.5KB OTP memory stores fixed feature sets such as mirror position presets or lighting sequences that never need firmware updates after production.
Recommended
Sensor Interface Boards
The PIC16C64AT-04/L serves as a low-cost front-end processor on sensor interface PCBs that aggregate digital sensors, debounce mechanical switches, and stream formatted data over UART or SPI. With 33 I/O the MCU can fan out to multiple SPI sensor buses while the 4MHz core executes the main scan loop. The 128-byte RAM buffers per-sensor samples before forwarding to a host controller over a serial link.
Recommended
Human-Machine Interface (HMI) Panels
Simple HMI panels with 4x4 keypads and character LCD displays are well-served by the PIC16C64AT-04/L. The 33 I/O pins can scan a 4x4 matrix, drive a 16x2 character LCD in 4-bit mode, and control status LEDs simultaneously. The 3.5KB OTP EPROM holds keypad lookup tables, menu state machines, and LCD custom-character bitmaps. The deterministic 1us instruction cycle keeps key debounce timing tight.
Recommended
Prototyping and Educational Development
The PLCC package is socketable, making the PIC16C64AT-04/L attractive for university labs and engineering prototyping where the MCU is repeatedly removed and re-programmed (in a separate EPROM eraser/programmer). The 44-pin PLCC breakout boards are widely available at low cost. The PIC16C64A instruction set is documented in textbooks, and 3.5KB OTP gives students enough headroom to write meaningful real-time kernels.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C64AT-04/L — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C64A-04/L | PIC16C64A-04I/L | PIC16C64A-10/L | PIC16C64A-04E/L | PIC16F877A-I/L |
|---|---|---|---|---|---|---|
| Package | 44-PLCC (J-Lead) | 44-PLCC (J-Lead) - same | 44-PLCC (J-Lead) - same | 44-PLCC (J-Lead) - same | 44-PLCC (J-Lead) - same | 44-PLCC (J-Lead) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Program Memory | 3.5 KB OTP EPROM | 3.5 KB OTP EPROM | 3.5 KB OTP EPROM | 3.5 KB OTP EPROM | 3.5 KB OTP EPROM | 14 KB Flash (4x larger, rewriteable) |
| Max Clock Frequency | 4 MHz | 4 MHz | 4 MHz | 10 MHz | 4 MHz | 20 MHz |
| Temperature Grade | Commercial (0C to +70C) | Commercial | Industrial (-40C to +85C) | Commercial | Extended (-40C to +125C) | Industrial (-40C to +85C) |
| Memory Type | OTP EPROM (one-time programmable) | OTP EPROM | OTP EPROM | OTP EPROM | OTP EPROM | Flash (in-circuit reprogrammable) |
| RAM | 128 bytes | 128 bytes | 128 bytes | 128 bytes | 128 bytes | 368 bytes |
| I/O Pins | 33 | 33 | 33 | 33 | 33 | 33 (same) |
| Packaging Format | Tape & Reel (T suffix) | Tube / Tray (no T suffix) | Tube / Tray | Tube / Tray | Tube / Tray | Tube / Tray |
Key Differentiators
- Tape & Reel packaging format for high-volume SMD assembly (vs PIC16C64A-04/L (non-T variant))
- Same memory/peripherals as industrial grade at commercial temperature (vs PIC16C64A-04I/L (industrial grade))
- Modern flash-based replacement exists with full pin compatibility (vs PIC16F877A-I/L (flash upgrade))
Design Notes
Estimated: at 5V supply and 4MHz clock with all 33 I/O pins actively switching, the PIC16C64AT-04/L draws approximately 15-20 mA of active current. VDD and VSS each appear twice on the 44-pin PLCC (pins 10/11 and 31/32) - both pairs must be connected. Place a 100nF decoupling capacitor within 5mm of each VDD pin and a bulk 10uF tantalum or ceramic at the board entry point. The MCU has no internal voltage regulator, so VDD noise above 50mV ripple can corrupt OTP read cycles during firmware execution.
The 44-pin PLCC J-lead footprint has a recommended land pattern of 1.27mm (50 mil) pitch with rectangular pads approximately 0.6mm wide. For socketed designs, choose a through-hole PLCC socket with retention clips to prevent the chip from vibrating loose in high-shock environments. For surface-mount reflow, the J-leads require standard SMD profiles with peak temperature not exceeding 220C for under 60 seconds to protect the plastic body. Place a ground pour under and around the package to reduce EMI susceptibility on the oscillator pins.
Critical: OTP EPROM memory cannot be erased or rewritten. Once programmed, the firmware is permanent - design and pre-program validation must be fully completed before production programming. The Watchdog Timer is not enabled by default and must be software-configured via the OPTION register; leaving WDT disabled means the system cannot recover from software crashes in the field. The MCLR pin (pin 41) is active-low and should be tied to VDD through a 10kohm resistor with a 100nF capacitor for noise filtering - floating MCLR causes spurious resets.
Keep the crystal or resonator within 10mm of OSC1 (pin 12) and OSC2 (pin 13) with short traces and a guarded ground ring to prevent noise coupling. Estimated: stray capacitance above 20pF on these pins can shift the oscillator frequency or prevent startup. For 4MHz operation, either a 4MHz crystal with two 22pF load capacitors or a ceramic resonator with built-in capacitors is recommended. Avoid routing high-frequency switching signals (relay coils, TRIAC commutation) near the oscillator traces as they couple through parasitic capacitance and destabilize the clock.
Compliance Information
Compliance status not explicitly stated in verified web data. PIC16C64A is a legacy product family; RoHS compliance for the commercial-temperature -04/L variant should be verified with Microchip directly before specification in new designs targeting EU markets.
