PIC16C65BT-04/PT - 8-Bit OTP MCU, 7KB, 4MHz, 44-TQFP | Microchip
MPN: PIC16C65BT-04/PT ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $12.5 | $12.50 |
| 10 | $11.25 | $112.50 |
| 100 | $9.85 | $985.00 |
| 500 | $8.65 | $4,325.00 |
| 1,000 | $7.5 | $7,500.00 |
PIC16C65BT-04/PT Overview
A microcontroller (MCU) is a single-chip computer that integrates a CPU, memory (program + data), and programmable I/O peripherals. The PIC16CXX family uses a Harvard architecture with separate program and data buses, which allows instruction fetch and operand read to occur in the same cycle. Within the broader taxonomy, the PIC16C65B sits as an OTP (one-time-programmable) variant of the mid-range PIC16 line, itself part of the 8-bit PIC microcontroller hierarchy, ultimately belonging to the embedded microcontroller -> semiconductor device -> integrated circuit family.
Key features include 4 MHz maximum operating frequency, an external oscillator interface, 192 x 8 RAM, 33 I/O pins, a 14-bit instruction word, and 7KB of OTP program memory that can be written once and thereafter behaves like ROM. The OTP technology makes the part well suited to volume production runs where firmware is finalized, while keeping per-unit cost lower than windowed EPROM or flash parts.
Architecturally the device uses a RISC core with a fixed instruction set, hardware multiplier, and peripheral set typical of the PIC16C6x family. The 33 I/O pins share package pins with on-chip peripherals, including parallel ports, timers, and a synchronous serial port. The OTP memory is programmed via the standard PIC ICSP protocol; in-circuit serial programming is supported through dedicated RB6/RB7 pins, allowing firmware loading after PCB assembly.
Typical applications include industrial control, motor control front-ends, automotive body and chassis subsystems, white goods and appliance controllers, and embedded control boards in 5V logic systems. The wide commercial temperature range and rugged PIC16C silicon make the part popular in long-life industrial equipment. The 44-TQFP package supports surface-mount assembly in compact designs where 33+ I/O lines are required.
When designing with this part, note that OTP memory cannot be erased or rewritten; firmware must be fully validated before committing to programming. Stocking the matched flash variant (PIC16F series with the same pinout) is recommended for development and field updates. The 5V-only core limits it to legacy 5V rails; new designs should consider 3.3V-capable PIC16F or PIC18 alternatives unless 5V tolerance is required.
This page synthesizes distributor pricing, pin-compatible PIC16C6x drop-in alternatives, and practical design notes not aggregated in a single view on the manufacturer datasheet.
Drop-in alternatives for PIC16C65BT-04/PT — 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 PIC16C65BT-04/PT (same form factor and footprint) — differing in Program Memory Size, Package, Program Memory Type, Timers, Mounting Type.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C65B-04I/P
✅ Drop-In✓ In Stock
$3.75 / Unit
View Datasheet →PIC16C65B-04E/P
✅ Drop-In✓ In Stock
$5.45 / Unit
View Datasheet →PIC16C65AT-04I/PT
✅ Drop-In✓ In Stock
$4.5 / Unit
View Datasheet →PIC16C65A-04I/P
✅ Drop-In✓ In Stock
$5.25 / Unit
View Datasheet →PIC16F877A-I/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C65BT-04/PT Maximum Ratings & Electrical Characteristics
| Manufacturer | Microchip Technology |
| Series | PIC 16C |
| Core Processor | PIC |
| Core Size | 8-Bit |
| Program Memory Size | 7KB (4K x 14) OTP |
| RAM Size | 192 x 8 bytes |
| Number of I/O | 33 |
| Speed | 4 MHz |
| Supply Voltage | 5 V (typical) |
| Oscillator Type | External |
| Operating Temperature | 0C to +70C (Commercial) |
| Package / Case | 44-TQFP (10x10 mm) |
| Mounting Type | Surface Mount |
| Packaging | Tape & Reel (TR) |
| Program Memory Type | OTP (One-Time Programmable) |
| Instruction Set Architecture | RISC, Harvard |
PIC16C65BT-04/PT Pin Configuration
| Pin 1 | MCLR/VPP — Master Clear (Reset) input / Programming voltage |
| Pin 2 | RA0/AN0 — Port A bit 0 / Analog input 0 |
| Pin 3 | RA1/AN1 — Port A bit 1 / Analog input 1 |
| Pin 4 | RA2/AN2 — Port A bit 2 / Analog input 2 |
| Pin 5 | RA3/AN3/VREF+ — Port A bit 3 / Analog input 3 / VREF+ |
| Pin 6 | RA4/T0CKI — Port A bit 4 / Timer0 clock input |
| Pin 7 | RA5/AN4/SS — Port A bit 5 / Analog input 4 / SPI Slave Select |
| Pin 8 | RE0/RD/AN5 — Port E bit 0 / Parallel port read control |
| Pin 9 | RE1/WR/AN6 — Port E bit 1 / Parallel port write control |
| Pin 10 | RE2/CS/AN7 — Port E bit 2 / Parallel port chip select |
| Pin 11 | VSS — Ground |
| Pin 12 | VDD — Positive supply (5V) |
| Pin 13 | OSC1/CLKIN — Oscillator crystal input / external clock in |
| Pin 14 | OSC2/CLKOUT — Oscillator crystal output / clock out |
| Pin 15 | RC0/T1OSO/T1CKI — Port C bit 0 / Timer1 oscillator output |
| Pin 16 | RC1/T1OSI/CCP2 — Port C bit 1 / Timer1 oscillator in / CCP2 |
| Pin 17 | RC2/CCP1 — Port C bit 2 / Capture/Compare/PWM1 |
| Pin 18 | RC3/SCK/SCL — Port C bit 3 / SPI clock / I2C clock |
| Pin 19 | RD0/PSP0 — Port D bit 0 / Parallel Slave Port bit 0 |
| Pin 20 | RD1/PSP1 — Port D bit 1 / Parallel Slave Port bit 1 |
| Pin 21 | RD2/PSP2 — Port D bit 2 / Parallel Slave Port bit 2 |
| Pin 22 | RD3/PSP3 — Port D bit 3 / Parallel Slave Port bit 3 |
| Pin 23 | RC4/SDI/SDA — Port C bit 4 / SPI data in / I2C data |
| Pin 24 | RC5/SDO — Port C bit 5 / SPI data out |
| Pin 25 | RC6/TX/CK — Port C bit 6 / USART transmit / clock |
| Pin 26 | RC7/RX/DT — Port C bit 7 / USART receive / data |
| Pin 27 | RD4/PSP4 — Port D bit 4 / Parallel Slave Port bit 4 |
| Pin 28 | RD5/PSP5 — Port D bit 5 / Parallel Slave Port bit 5 |
| Pin 29 | RD6/PSP6 — Port D bit 6 / Parallel Slave Port bit 6 |
| Pin 30 | RD7/PSP7 — Port D bit 7 / Parallel Slave Port bit 7 |
| Pin 31 | VSS — Ground |
| Pin 32 | VDD — Positive supply (5V) |
| Pin 33 | RB0/INT — Port B bit 0 / External interrupt |
| Pin 34 | RB1 — Port B bit 1 |
| Pin 35 | RB2 — Port B bit 2 |
| Pin 36 | RB3/PGM — Port B bit 3 / LVP programming input |
| Pin 37 | RB4 — Port B bit 4 |
| Pin 38 | RB5 — Port B bit 5 |
| Pin 39 | RB6/PGC — Port B bit 6 / ICSP clock |
| Pin 40 | RB7/PGD — Port B bit 7 / ICSP data |
| Pin 41 | NC — Not connected (per datasheet) |
| Pin 42 | NC — Not connected (per datasheet) |
| Pin 43 | NC — Not connected (per datasheet) |
| Pin 44 | NC — Not connected (per datasheet) |
Typical Applications
PIC16C65BT-04/PT is suitable for 6 applications: Industrial Process Control, Appliance Control Boards, Automotive Body and Chassis Modules, Embedded Data Acquisition Front-Ends, HVAC Control and Building Automation, Legacy Embedded Product Maintenance.
Industrial Process Control
The PIC16C65BT-04/PT fits industrial process control boards where 33 digital I/O lines can interface to pushbuttons, indicator LEDs, relay drivers, and discrete sensors. Its 7KB OTP program memory holds typical PID and state-machine firmware, while the 192-byte RAM supports modest data buffering. The 4 MHz clock provides 1 MIPS throughput, sufficient for sub-millisecond control loop updates in conveyor, pump, and valve control systems.
Recommended
Appliance Control Boards
White goods and appliance controllers (washing machines, dishwashers, microwave ovens) historically use PIC16C65B-family MCUs because OTP memory locks firmware at production cost. The PIC16C65BT-04/PT's 33 I/O pins connect to keypad matrices, seven-segment displays, triac drivers, and motor encoder inputs. Commercial 0C to +70C operation covers indoor appliance environments, and the 5V supply aligns with legacy appliance power architectures.
Recommended
Automotive Body and Chassis Modules
Although the commercial-temperature PIC16C65BT-04/PT is not automotive-qualified, the broader PIC16C65B family is widely deployed in non-safety automotive body electronics such as seat controllers, mirror adjusters, and lighting modules. The 33 I/O lines drive multiple H-bridges and LED strings via external drivers. Designers targeting AEC-Q100 must select PIC16C variants carrying the -I or -E extended temperature suffix instead.
Recommended
Embedded Data Acquisition Front-Ends
The PIC16C65BT-04/PT serves as a front-end controller in low-channel-count data acquisition systems where 33 I/O lines multiplex analog inputs through external analog switches and sample-and-hold circuits. Its 4 MHz instruction rate supports conversion rates up to ~50 ksps when paired with a serial ADC. The 192-byte RAM buffers sample blocks before UART transmission to a host processor or display module.
Recommended
HVAC Control and Building Automation
HVAC zone controllers and building automation nodes use the PIC16C65BT-04/PT to read temperature sensors, switch relay outputs for fans and dampers, and drive character LCDs. The 33 I/O lines support multiple zone inputs plus an LCD interface and a keypad. OTP memory prevents firmware tampering by field installers, while 5V operation interfaces directly to legacy building-automation sensor networks.
Recommended
Legacy Embedded Product Maintenance
For manufacturers maintaining long-life embedded products originally designed around the PIC16C65B, the PIC16C65BT-04/PT provides a direct replacement source to sustain production runs. Its identical 44-TQFP pinout, 7KB OTP memory, and PIC16C6x peripheral set allow PCBs to be re-populated without redesign. Engineers should plan migration to PIC16F877A-I/PT for new revisions while keeping PIC16C stock for warranty service.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C65BT-04/PT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C65B-04I/P | PIC16C65B-04E/P | PIC16C65AT-04I/PT | PIC16C65A-04I/P | PIC16F877A-I/PT |
|---|---|---|---|---|---|---|
| Package | 44-TQFP (10x10 mm) | 44-TQFP - same | 44-TQFP - same | 44-TQFP (PT) - same | 44-TQFP - same | 44-TQFP (PT) - same |
| Brand | Microchip Technology | Microchip Technology - same brand | Microchip Technology - same brand | Microchip Technology - same brand | Microchip Technology - same brand | Microchip Technology - same brand |
| Program Memory Type | OTP (7KB / 4K x 14) | OTP (7KB) | OTP (7KB) | OTP (7KB) | EPROM (7KB) | Flash (14KB) |
| Maximum Clock Speed | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 20 MHz |
| RAM Size | 192 bytes | 192 bytes | 192 bytes | 192 bytes | 192 bytes | 368 bytes |
| Operating Temperature | 0C to +70C (Commercial) | -40C to +85C (Industrial) | -40C to +125C (Extended) | -40C to +85C (Industrial) | -40C to +85C (Industrial) | -40C to +85C (Industrial) |
| Supply Voltage | 5 V (typical) | 5 V | 5 V | 5 V | 5 V | 2.0 V to 5.5 V |
| Field Firmware Update | No (OTP memory) | No (OTP) | No (OTP) | No (OTP) | No (EPROM, UV-erase window) | Yes (Flash) |
Key Differentiators
- Wider commercial temp range availability for cost-sensitive designs (vs PIC16C65B-04I/P)
- Tape and reel packaging for high-volume SMT assembly (vs PIC16C65B-04I/PQ)
- Proven legacy silicon with extensive tooling support (vs PIC16F877A-I/PT)
Design Notes
The PIC16C65BT-04/PT draws typically 5 mA at 4 MHz and 5V across all I/O states; add a 100 nF decoupling capacitor close to VDD (pin 12 and 32) and a 10 uF bulk capacitor on the supply rail. Brown-out conditions can corrupt OTP program memory indirectly via undefined I/O behavior, so a voltage supervisor such as MCP100 is recommended for production designs, especially in industrial environments.
OTP program memory on the PIC16C65BT-04/PT can be written only once. A failed or aborted ICSP programming session may still consume device resources depending on the algorithm used. For development, use the flash equivalent PIC16F877A-I/PT to validate firmware, then commit to PIC16C65BT only when the firmware is fully frozen. Verify programming voltages (VDD = 5V, VPP = 13V typical) per Microchip programming specification to avoid partial programming.
Route the external crystal traces to OSC1 (pin 13) and OSC2 (pin 14) as short, symmetric paths with a ground guard ring, and place the load capacitors within 5 mm of the pins. Keep the MCLR/VPP line (pin 1) free of nearby switching signals to prevent spurious resets. If low-voltage programming (LVP) is used, leave pin RB3/PGM (pin 36) accessible and decouple it with 100 nF to ground.
Compliance Information
RoHS and REACH compliance not specified in the verified distributor data; Microchip legacy OTP parts historically transition to lead-free finishes as catalog parts become obsolete. AEC-Q100 does not apply to the commercial-temperature -04/PT variant; the -I and -E temperature suffix variants of the PIC16C65B family are also not formally AEC-Q100 qualified. Always confirm compliance with the latest manufacturer certificate of conformance before volume commitment.