PIC16C65B-04I/P - 8-Bit 4MHz 7KB OTP MCU 40-PDIP | Microchip
MPN: PIC16C65B-04I/P ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $5.86 | $5.86 |
| 10 | $5.27 | $52.70 |
| 100 | $4.69 | $469.00 |
| 500 | $4.21 | $2,105.00 |
| 1,000 | $3.75 | $3,750.00 |
PIC16C65B-04I/P Overview
Background: A microcontroller (MCU) is a single-chip computer containing a CPU core, program memory, RAM, and integrated peripherals. PIC microcontrollers from Microchip employ a Harvard RISC architecture with separate program and data buses, which allows single-cycle instruction execution (except program branches, which take two cycles). The PIC16C mid-range family — the lineage to which the PIC16C65B belongs — provides a low-cost entry point with a 14-bit instruction word, 35 single-word instructions, and a peripheral-rich architecture that targets embedded control applications from appliance timers to industrial sensor interfaces.
Key features of the PIC16C65B-04I/P include its OTP EPROM-based program memory (one-time programmable, ideal for mature production designs), a wide operating voltage range from 2.5V to 6.0V, low-power consumption (typical 15 uA at 5V/4 MHz and 1 uA at 3V/32 kHz), a high-performance RISC CPU with only 35 instructions to learn, and a fully static design that allows clock frequencies down to DC. The 4 MHz maximum clock speed makes this part the lowest-speed member of the PIC16C65B family (compared to 10 MHz and 20 MHz variants) and is typically selected for cost-sensitive, low-speed control loops.
Typical applications for the PIC16C65B-04I/P include industrial sensor conditioning front-ends, appliance controllers (washing machines, microwave ovens, HVAC), automotive body electronics (non-safety subsystems), instrumentation with analog sensor inputs, and legacy embedded designs that require OTP memory and a parallel slave port for inter-MCU communication. The integrated 8-bit ADC simplifies designs that read potentiometers, temperature sensors, or analog transducers directly.
When designing with the PIC16C65B-04I/P, note that OTP memory is one-time-programmable and cannot be erased; for prototyping and field-upgradable designs consider a Flash-based PIC16F6x or PIC18F equivalent in the same PDIP-40 footprint. Industrial temperature rating (-40C to +85C) is suitable for outdoor enclosures and factory environments. Always confirm oscillator configuration and watchdog timer settings in MPLAB before committing to OTP programming.
This page synthesizes distributor pricing, drop-in alternatives in the same 40-PDIP package, and practical design notes not found in the manufacturer datasheet alone.
Drop-in alternatives for PIC16C65B-04I/P — 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 PIC16C65B-04I/P (same form factor and footprint) — differing in Package, Timers, Program Memory Type, Mounting Type, Program Memory Size.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C65B-04/PQ
✅ Drop-In✓ In Stock
$10.25 / Unit
View Datasheet →PIC16C65B-04E/P
✅ Drop-In✓ In Stock
$5.45 / Unit
View Datasheet →PIC16C65B-04E/PQ
✅ Drop-In✓ In Stock
$11.1 / Unit
View Datasheet →PIC16C65A-04I/P
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$5.25 / Unit
View Datasheet →PIC16C65AT-04I/PT
✅ Drop-In✓ In Stock
$4.5 / Unit
View Datasheet →PIC16C65B-04I/P Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC16C Mid-Range 8-bit RISC |
| Program Memory Size | 7 KB (4K x 14) OTP EPROM |
| RAM Size | 192 bytes |
| CPU Speed | 4 MHz maximum |
| Supply Voltage Range | 2.5 V to 6.0 V |
| I/O Pins | 33 |
| Timers | 3 (Timer0, Timer1, Timer2) |
| CCP Modules | 2 (Capture/Compare/PWM) |
| Serial Interfaces | 1x SSP (SPI/I2C), 1x USART |
| Parallel Slave Port | Yes (8-bit) |
| ADC | 8-channel, 8-bit |
| Package | 40-pin PDIP (0.600 in, 15.24 mm) |
| Operating Temperature | -40 C to +85 C (Industrial) |
| Instruction Set | 35 single-word instructions, 14-bit wide |
| Instruction Cycle | 1 cycle (4 clocks), 2 cycles for branches |
| Mounting Type | Through-hole (PDIP) |
| MSL Level | Not applicable (through-hole) |
| RoHS Status | Compliant |
| Lead-Free | Yes |
PIC16C65B-04I/P Pin Configuration
| Pin 1 | RA0/AN0 — Port A bit 0 / Analog input 0 |
| Pin 2 | RA1/AN1 — Port A bit 1 / Analog input 1 |
| Pin 3 | RA2/AN2 — Port A bit 2 / Analog input 2 |
| Pin 4 | RA3/AN3/VREF+ — Port A bit 3 / Analog input 3 / ADC VREF+ |
| Pin 5 | RA4/T0CKI — Port A bit 4 / Timer0 clock input |
| Pin 6 | RA5/AN4/SS — Port A bit 5 / Analog input 4 / SPI Slave Select |
| Pin 7 | RE0/RD/AN5 — Port E bit 0 / Parallel Slave Port read / Analog input 5 |
| Pin 8 | RE1/WR/AN6 — Port E bit 1 / Parallel Slave Port write / Analog input 6 |
| Pin 9 | RE2/CS/AN7 — Port E bit 2 / Parallel Slave Port CS / Analog input 7 |
| Pin 10 | VDD — Positive supply voltage (2.5V to 6.0V) |
| Pin 11 | VSS — Ground reference |
| Pin 12 | OSC1/CLKIN — Crystal oscillator input / external clock input |
| Pin 13 | OSC2/CLKOUT — Crystal oscillator output / clock output |
| Pin 14 | MCLR/VPP — Master clear (reset) / programming voltage input |
| Pin 15 | RC0/T1OSO/T1CKI — Port C bit 0 / Timer1 oscillator output / Timer1 clock input |
| Pin 16 | RC1/T1OSI/CCP2 — Port C bit 1 / Timer1 oscillator input / CCP2 I/O |
| Pin 17 | RC2/CCP1 — Port C bit 2 / CCP1 I/O |
| Pin 18 | RC3/SCK/SCL — Port C bit 3 / SSP SPI clock / I2C clock |
| Pin 19 | RD0/PSP0 — Port D bit 0 / Parallel Slave Port data bit 0 |
| Pin 20 | RD1/PSP1 — Port D bit 1 / Parallel Slave Port data bit 1 |
| Pin 21 | RD2/PSP2 — Port D bit 2 / Parallel Slave Port data bit 2 |
| Pin 22 | RD3/PSP3 — Port D bit 3 / Parallel Slave Port data bit 3 |
| Pin 23 | RC4/SDI/SDA — Port C bit 4 / SSP SPI data in / I2C data |
| Pin 24 | RC5/SDO — Port C bit 5 / SSP SPI data out |
| Pin 25 | RC6/TX/CK — Port C bit 6 / USART TX / USART clock |
| Pin 26 | RC7/RX/DT — Port C bit 7 / USART RX / USART data |
| Pin 27 | RD4/PSP4 — Port D bit 4 / Parallel Slave Port data bit 4 |
| Pin 28 | RD5/PSP5 — Port D bit 5 / Parallel Slave Port data bit 5 |
| Pin 29 | RD6/PSP6 — Port D bit 6 / Parallel Slave Port data bit 6 |
| Pin 30 | RD7/PSP7 — Port D bit 7 / Parallel Slave Port data bit 7 |
| Pin 31 | VSS — Ground reference |
| Pin 32 | VDD — Positive supply voltage (2.5V to 6.0V) |
| 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/PGC — Port B bit 6 / ICSP clock |
| Pin 40 | RB7/PGD — Port B bit 7 / ICSP data |
Typical Applications
PIC16C65B-04I/P is suitable for 6 applications: Industrial Sensor Conditioning, Appliance Control (Washing Machine / Microwave / HVAC), Automotive Body Electronics (Non-Safety), Test and Measurement Instrumentation, Legacy Embedded Designs / Parallel-Port Inter-MCU, Power Management and Battery Monitoring.
Industrial Sensor Conditioning
The PIC16C65B-04I/P fits industrial sensor-conditioning front-ends because its 8-channel 8-bit ADC handles up to 8 analog transducers (thermistors, strain gauges, pressure sensors) while the 33 I/O pins drive status LEDs and digital isolators. With 7KB OTP for calibration tables and linearization curves, plus industrial -40C to +85C rating for factory-floor operation, the part simplifies PLC analog-input modules. At 4 MHz the CPU performs a full ADC read and filter loop in under 100 microseconds, fast enough for 1 kHz sensor sampling.
Recommended
Appliance Control (Washing Machine / Microwave / HVAC)
White-goods controllers are a classic application for the PIC16C65B-04I/P, where its OTP memory suits mature high-volume production, the integrated USART connects to inverter boards, and the PWM modules drive motor triac control. The 33 I/O pins handle keypad scanning, 7-segment display multiplexing, and relay drivers from a single MCU. Industrial temperature rating supports unheated laundry-room or garage installations. At 4 MHz, scan loops and debounce routines run well within the few-millisecond response budget of user-interface updates.
Recommended
Automotive Body Electronics (Non-Safety)
Non-safety body-electronics modules such as seat controllers, mirror adjusters, and HVAC blend doors can use the PIC16C65B-04I/P at 4 MHz to manage multiple analog inputs (position potentiometers) and PWM outputs (motor drivers). The SSP peripheral supports SPI communication with dashboard master MCUs, and the parallel slave port enables high-throughput data exchange with cluster processors. Industrial -40C to +85C rating covers cabin environments; for under-hood modules consider PIC16C65B-04E/P with extended temperature.
Recommended
Test and Measurement Instrumentation
Bench-top instruments benefit from the PIC16C65B-04I/P's 8-bit ADC (for direct measurement of analog front-ends), USART (for SCPI command parsing from a host PC), and 33 I/O pins (for front-panel button matrix and rotary encoder inputs). The 7KB OTP stores calibration constants, instrument state-machine code, and serial protocols. Low 15 uA active current at 5V/4 MHz keeps thermal budget manageable in enclosed instrument cases, while the parallel slave port enables shared-bus architectures with a DSP or FPGA co-processor.
Recommended
Legacy Embedded Designs / Parallel-Port Inter-MCU
Designs that use the PIC16C65B-04I/P's 8-bit parallel slave port for inter-MCU data exchange — a pattern common in 1990s industrial controllers — can continue using this part for maintenance and refurbishment of legacy equipment. Two PIC16C65B chips can exchange a full byte in one instruction cycle over the parallel port, enabling shared-memory or mailbox architectures between a host controller and a co-processor. Industrial temperature rating suits factory retrofit environments.
Recommended
Power Management and Battery Monitoring
Battery monitoring boards use the PIC16C65B-04I/P's 8-channel ADC to sample cell voltages, charge current, and temperature sensors, while the CCP/PWM modules drive balancing FETs in multi-cell battery packs. The 4 MHz clock supports periodic ADC sweeps every few milliseconds with the MCU sleeping between conversions for low average current draw. OTP memory holds cell-chemistry lookup tables (Li-ion, NiMH, lead-acid) and protection thresholds that never change in production.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C65B-04I/P — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C65B-04/P | PIC16C65B-04E/P | PIC16C65B-04E/PQ | PIC16C65A-04I/P | PIC16C65AT-04I/PT |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 40-PDIP (0.600 in) | 40-PDIP (0.600 in) - same | 40-PDIP (0.600 in) - same | 40-PDIP (0.600 in) - same | 40-PDIP (0.600 in) - same | 40-PDIP carrier - same |
| Program Memory | 7 KB OTP | 7 KB OTP | 7 KB OTP | 7 KB OTP | 7 KB OTP | 7 KB OTP |
| Maximum Clock Speed | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 4 MHz |
| Operating Temperature | -40C to +85C (Industrial) | 0C to +70C (Commercial) | -40C to +125C (Extended) | -40C to +125C (Extended) | -40C to +85C (Industrial) | -40C to +85C (Industrial) |
| I/O Pins | 33 | 33 | 33 | 33 | 33 | 33 |
| ADC | 8-ch 8-bit | 8-ch 8-bit | 8-ch 8-bit | 8-ch 8-bit | 8-ch 8-bit | 8-ch 8-bit |
| Memory Type | OTP EPROM | OTP EPROM | OTP EPROM | OTP EPROM | OTP EPROM | OTP EPROM |
| Lifecycle Status | Active | Active | Active | Active | Active | Active |
Key Differentiators
- Extended temperature range option in same footprint (vs PIC16C65B-04E/P)
- Industrial temperature rating vs commercial (vs PIC16C65B-04/P)
- Tape-and-reel carrier variant for high-volume assembly (vs PIC16C65AT-04I/PT)
Design Notes
OTP (One-Time-Programmable) EPROM memory cannot be erased after programming. Unlike Flash-based PIC16F variants, code bugs locked into OTP cannot be fixed without replacing the chip. Always validate firmware on a Flash-equipped PIC16F65-04I/P (pin-compatible) or PIC18F45K22 substitute before committing the final firmware to OTP parts for production.
The PIC16C65B-04I/P typically draws 15 uA at 5V/4 MHz and 1 uA at 3V/32 kHz per the datasheet. For battery-powered designs using sleep mode, ensure the watchdog timer and brown-out reset are configured correctly to avoid extra current draw. Decoupling VDD with 100 nF ceramic close to pins 11 and 32 (both VSS/VDD pairs) plus 10 uF bulk at the regulator output prevents ADC reference noise from corrupting analog readings.
Place the decoupling capacitor within 5 mm of VDD/VSS pins and keep the crystal oscillator traces short (under 10 mm) and surrounded by a ground pour to reduce EMI pickup. Analog inputs (RA0-RA5, RE0-RE2) should be routed away from the digital switching lines on ports RD and RC to minimize ADC crosstalk. If using the parallel slave port, ensure data-strobe timing matches the master MCU's setup/hold requirements in the datasheet timing diagrams.
Estimated: at 4 MHz and 5V supply, the PIC16C65B-04I/P dissipates approximately 25 mW (5 mA typical active current). The 40-pin PDIP package has theta_JA around 50 C/W, giving a junction-temperature rise of only 1.25 C above ambient at full active load. Thermal management is not a concern in this package, but verify in-system by measuring VDD current during peak ADC + PWM activity to confirm the design margin.
Compliance Information
RoHS and REACH compliant per Microchip product declaration. Not AEC-Q100 qualified — choose PIC16C65B-04E/PQ or dedicated automotive PIC MCUs for AEC-Q100 applications. Lead-free PDIP package per Microchip manufacturing standards.
