PIC16C65B-04E/PQ - 8-Bit 4MHz OTP MCU, 7KB, 44-MQFP | Microchip
MPN: PIC16C65B-04E/PQ ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $18.5 | $18.50 |
| 10 | $16.2 | $162.00 |
| 100 | $14.05 | $1,405.00 |
| 500 | $12.4 | $6,200.00 |
| 1,000 | $11.1 | $11,100.00 |
PIC16C65B-04E/PQ Overview
A microcontroller (MCU) is a single-chip computer that integrates a CPU, program memory (ROM/EPROM/Flash/OTP), data RAM, peripherals and I/O on one die. The PIC16C6X mid-range family sits in Microchip's PICmicro hierarchy as: PIC16C65B -> PIC16C6X -> PIC16C mid-range -> PICmicro -> 8-bit MCU -> microcontroller -> embedded processor. OTP versions like the PIC16C65B are intended for cost-optimized production runs where firmware is finalized at the factory, while their Flash-based PIC16F successors are used when in-field reprogrammability is required.
Key features include a 14-bit instruction word, three hardware timers (TMR0, TMR1, TMR2), an 8-bit PWM module with Capture/Compare/PWM (CCP), a 10-bit multi-channel Analog-to-Digital Converter (ADC) with 8 channels, a Universal Synchronous/Asynchronous Receiver/Transmitter (USART) for serial communications, a Serial Peripheral Interface (SPI) bus, and an Inter-Integrated Circuit (I2C) bus. The '04' speed grade corresponds to a 4 MHz oscillator, and the 'E' suffix designates the Extended temperature range of -40 C to +125 C. Brown-out Reset (BOR), Power-on Reset (POR), and a Watchdog Timer (WDT) provide system-level robustness for industrial and automotive deployments.
Typical applications include industrial automation controllers, HVAC interface boards, automotive body and chassis subsystems, white-goods user-interface modules, sensor-conditioning front-ends, motor-control peripherals, and general-purpose serial communication hubs that benefit from the device's on-chip I2C/SPI/USART mix. The 33 I/O count and 44-pin MQFP footprint also make the part a frequent choice when migrating older PIC16C6X designs to long-lifecycle platforms.
When designing with this device, evaluate whether OTP is acceptable for the production volume or whether a Flash-based PIC16F equivalent would reduce manufacturing risk. Use the MPLAB PM3 programmer (referenced in the Microchip product page) for production programming, and verify that oscillator stability is maintained across the extended -40 C to +125 C window.
This page synthesizes distributor pricing, parametric drop-in alternatives in the same MQFP-44 footprint, and practical design notes that go beyond the manufacturer datasheet narrative.
Drop-in alternatives for PIC16C65B-04E/PQ — 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-04E/PQ (same form factor and footprint) — differing in Package, Timers, Mounting Type, Program Memory Size, RAM Size.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C65B-04I/PQ
✅ Drop-In✓ In Stock
$5.45 / Unit
View Datasheet →PIC16C65B-04/PQ
✅ Drop-In✓ In Stock
$10.25 / Unit
View Datasheet →PIC16C65B-04E/L
✅ Drop-In✓ In Stock
$10.85 / Unit
View Datasheet →PIC16C65B-04E/PT
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$2.62 / Unit
View Datasheet →PIC16C65A-20E/PQ
✅ Drop-In✓ In Stock
$4.85 / Unit
View Datasheet →PIC16C65B-04E/PQ Maximum Ratings & Electrical Characteristics
| Core | PIC16C mid-range 8-bit |
| Program Memory Type | OTP (One-Time Programmable) EPROM |
| Program Memory Size | 7 KB (4K x 14 words) |
| RAM Size | 192 x 8 bytes |
| EEPROM Size | 0 bytes (none on die) |
| CPU Speed (Max) | 4 MHz |
| Instruction Cycle | 200 ns (4-clock, 4 MHz oscillator) |
| Operating Voltage Range | 2.5 V to 6.0 V |
| I/O Pins | 33 |
| Timers | 3 (TMR0, TMR1, TMR2) |
| PWM / CCP | 1 CCP module, 8-bit PWM |
| ADC | 8 channels x 10-bit (8-bit conversion in some modes) |
| Connectivity | I2C, SPI, UART/USART |
| Package | 44-MQFP (10 mm x 10 mm), PQ suffix |
| Mounting Type | Surface Mount (gull-wing leads) |
| Temperature Grade | Extended -40 C to +125 C (E suffix) |
| Typical Active Current | 15 uA at 5 V, 4 MHz |
| Typical Standby Current | 1 uA at 3 V, 32 kHz |
| Oscillator | External (XT/HS/LP/RC modes) |
| RoHS Status | Non-Compliant (legacy OTP windowed part) |
PIC16C65B-04E/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 3 / ADC VREF |
| Pin 5 | RA4/T0CKI — PORTA bit 4 / Timer 0 clock input |
| Pin 6 | RA5/SS/AN4 — PORTA bit 5 / SPI Slave Select / AN4 |
| Pin 7 | OSC1/CLKIN — Oscillator input / external clock |
| Pin 8 | OSC2/CLKOUT — Oscillator output / clock out |
| Pin 9 | RC0/T1OSO/T1CKI — PORTC bit 0 / Timer1 oscillator output / clock in |
| Pin 10 | RC1/T1OSI/CCP2 — PORTC bit 1 / Timer1 oscillator in / CCP2 |
| Pin 11 | RC2/CCP1 — PORTC bit 2 / Capture/Compare/PWM 1 |
| Pin 12 | RC3/SCK/SCL — PORTC bit 3 / SPI clock / I2C clock |
| Pin 13 | RC4/SDI/SDA — PORTC bit 4 / SPI data in / I2C data |
| Pin 14 | RC5/SDO — PORTC bit 5 / SPI data out |
| Pin 15 | RC6/TX/CK — PORTC bit 6 / USART TX / clock |
| Pin 16 | RC7/RX/DT — PORTC bit 7 / USART RX / data |
| Pin 17 | VSS — Ground |
| Pin 18 | VDD — Positive supply (2.5 V-6.0 V) |
| Pin 19 | RB0/INT — PORTB bit 0 / External interrupt |
| Pin 20 | RB1 — PORTB bit 1 |
| Pin 21 | RB2 — PORTB bit 2 |
| Pin 22 | RB3/PGM — PORTB bit 3 / LVP program |
| Pin 23 | RB4 — PORTB bit 4 |
| Pin 24 | RB5 — PORTB bit 5 |
| Pin 25 | RB6/PGC — PORTB bit 6 / ICSP clock |
| Pin 26 | RB7/PGD — PORTB bit 7 / ICSP data |
| Pin 27 | RE0/RD/AN5 — PORTE bit 0 / Read control / AN5 |
| Pin 28 | RE1/WR/AN6 — PORTE bit 1 / Write control / AN6 |
| Pin 29 | RE2/CS/AN7 — PORTE bit 2 / Chip select / AN7 |
| Pin 30 | RD0/PSP0 — PORTD bit 0 / Parallel Slave Port bit 0 |
| Pin 31 | RD1/PSP1 — PORTD bit 1 / PSP bit 1 |
| Pin 32 | RD2/PSP2 — PORTD bit 2 / PSP bit 2 |
| Pin 33 | RD3/PSP3 — PORTD bit 3 / PSP bit 3 |
| Pin 34 | RD4/PSP4 — PORTD bit 4 / PSP bit 4 |
| Pin 35 | RD5/PSP5 — PORTD bit 5 / PSP bit 5 |
| Pin 36 | RD6/PSP6 — PORTD bit 6 / PSP bit 6 |
| Pin 37 | RD7/PSP7 — PORTD bit 7 / PSP bit 7 |
| Pin 38 | VSS — Ground |
| Pin 39 | VDD — Positive supply |
| Pin 40 | MCLR/VPP — Master clear reset / programming voltage |
| Pin 41 | NC — Not connected |
| Pin 42 | NC — Not connected |
| Pin 43 | NC — Not connected |
| Pin 44 | NC — Not connected |
Typical Applications
PIC16C65B-04E/PQ is suitable for 7 applications: Industrial Automation Controllers, Automotive Body and Chassis Modules, HVAC Interface and Control Boards, White Goods and Appliance Controllers, Sensor Conditioning Front-Ends, Serial Communication Bridges, User Interface / Keypad / Display Modules.
Industrial Automation Controllers
The PIC16C65B-04E/PQ's 7 KB OTP, 192-byte RAM, and 33 I/O are well matched to mid-complexity industrial controllers such as PLCs, sensor I/O hubs, and motor-driver front-ends. The Extended -40 C to +125 C temperature grade guarantees operation in unheated cabinets, while the on-chip I2C/SPI/USART set directly drives sensor and HMI buses. The 4 MHz speed and 200 ns instruction cycle comfortably handle scan loops, PID updates, and protocol parsing. The OTP-only programming model suits mature, factory-firmware designs where per-unit cost dominates, since no on-board programming infrastructure is required. Pin-compatible drop-ins exist for lower temperature grades, simplifying supply-chain qualification across product families.
Recommended
Automotive Body and Chassis Modules
Within automotive body controllers (window lifters, mirror adjusters, climate/HVAC panels, instrument clusters), the PIC16C65B-04E/PQ offers the AEC-Q100-style Extended temperature range, on-chip USART for LIN-bus bridges, and PWM for motor drive. The 8-bit PIC core's deterministic 200 ns instruction timing simplifies real-time control loops, while 192 bytes of RAM is sufficient for state machines, debouncing, and serial frame buffers. The 33 I/O handle key switches, LEDs and relay drivers without external mux logic. Although the OTP memory requires factory programming, it eliminates field firmware-update risks in safety-critical modules. Production volume pricing below USD 12 per unit at 1000-piece quantities supports high-volume vehicle programs.
Recommended
HVAC Interface and Control Boards
Heating, ventilation and air-conditioning (HVAC) controllers benefit from the PIC16C65B-04E/PQ's on-chip ADC for temperature/humidity sensing, PWM outputs for fan and damper control, and USART for communication with master thermostats or building-management gateways. The Extended temperature rating supports operation near boilers and rooftop units where ambient can exceed 85 C. With 33 I/O, the MCU can directly drive LED/LCD user interfaces, keypad matrices, and relay coils without external logic, reducing the bill of materials. The 7 KB OTP memory is enough for proportional control loops, scheduling logic, and menu handling in residential and light-commercial HVAC designs.
Recommended
White Goods and Appliance Controllers
Washing machines, dishwashers, ovens and refrigerators rely on cost-optimized 8-bit MCUs like the PIC16C65B-04E/PQ for user-interface, motor-control and sensor-reading tasks. The PIC16C65B's PWM, ADC, I2C and USART peripherals cover keypad scanning, LED/LCD driving, motor triac firing, and serial diagnostics. The 7 KB OTP and 192-byte RAM comfortably fit state-machine firmware for cycle control and safety interlocks. The 44-MQFP surface-mount package enables automated pick-and-place assembly, while the Extended temperature grade tolerates the heat inside oven cavities or compressor compartments. The same MQFP-44 footprint across temperature grades simplifies PCB qualification for global product variants.
Recommended
Sensor Conditioning Front-Ends
Industrial sensor-conditioning boards use the PIC16C65B-04E/PQ to digitize analog inputs, linearize sensor curves, and forward processed data over I2C/SPI/USART to a host controller. The on-chip 8-channel ADC samples multiple transducers in sequence, while 192 bytes of RAM store calibration tables and averaging buffers. The MCU's 4 MHz execution rate handles 10-bit conversions, digital filtering, and serial framing in real time without DMA. Brown-out Reset and Watchdog Timer features ensure reliable recovery from brown-outs and firmware lockups in remote sensor installations. The Extended temperature grade supports outdoor and process-industry deployments.
Recommended
Serial Communication Bridges
The PIC16C65B-04E/PQ's combination of USART, SPI and I2C in one 44-MQFP package makes it a natural fit for protocol-conversion gateways (UART-SPI, I2C-UART, RS-232-to-RS-485). The 7 KB OTP accommodates protocol state machines and command parsing, while the 33 I/O expose additional handshake lines for flow control. The Extended -40 C to +125 C temperature grade allows deployment in outdoor enclosures, factory-floor cabinets, and vehicle telematics boxes. For developers, the same MQFP-44 footprint is shared across PIC16C65B and PIC16F7X family members, allowing field upgrades to Flash-based parts without PCB rework.
Recommended
User Interface / Keypad / Display Modules
The PIC16C65B-04E/PQ's 33 I/O are well suited to scanning 4x4 or larger keypads, driving multiplexed 7-segment or character LCDs, and controlling status LEDs. The PWM module can dim backlights or alert tones without additional timers, and the I2C port easily extends to external GPIO expanders or non-volatile memory for menu settings. The Extended temperature rating enables deployment in unheated kiosks, automotive dashboards, and outdoor point-of-sale terminals. With 7 KB OTP and 192-byte RAM, designers can implement debouncing, menu navigation, and multi-language strings in a single MCU without external memory. The MQFP-44 footprint supports both hand-prototype and high-volume SMT assembly lines.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C65B-04E/PQ — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C65B-04I/PQ | PIC16C65B-04/PQ | PIC16C65B-04E/L | PIC16C65B-04E/PT | PIC16C65A-20E/PQ |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 44-MQFP (10x10) | 44-MQFP (10x10) - same | 44-MQFP (10x10) - same | 44-CDIP (windowed) - different | 44-TQFP (10x10) - same footprint | 44-MQFP (10x10) - same |
| Max Frequency | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 20 MHz (5x faster) |
| Program Memory | 7 KB OTP (4K x 14) | 7 KB OTP | 7 KB OTP | 7 KB OTP (windowed, erasable) | 7 KB OTP | 7 KB OTP (older 'A' silicon) |
| RAM Size | 192 x 8 | 192 x 8 | 192 x 8 | 192 x 8 | 192 x 8 | 192 x 8 |
| I/O Pins | 33 | 33 | 33 | 33 | 33 | 33 |
| Temperature Grade | Extended -40 C to +125 C | Industrial -40 C to +85 C | Commercial 0 C to +70 C | Extended -40 C to +125 C | Extended -40 C to +125 C | Extended -40 C to +125 C |
| Mounting Type | Surface Mount (MQFP gull-wing) | Surface Mount (MQFP) | Surface Mount (MQFP) | Through-Hole (CDIP) | Surface Mount (TQFP) | Surface Mount (MQFP) |
| Reprogrammable | No (OTP) | No (OTP) | No (OTP) | Yes (windowed EPROM, UV-erasable) | No (OTP) | No (OTP) |
Key Differentiators
- Extended temperature grade for harsh environments (vs PIC16C65B-04I/PQ)
- MQFP-44 surface-mount form factor with 33 I/O (vs PIC16C65B-04E/L (44-CDIP windowed))
- Mature mid-range PIC16C core with abundant legacy support (vs PIC16C65A-20E/PQ)
Design Notes
Estimated: at 5 V VDD and 4 MHz active mode, the PIC16C65B-04E/PQ draws approximately 15 uA typical (per datasheet 30209D). For battery-backed designs, switching to the 32 kHz LP oscillator with the SLEEP instruction can drop standby current to about 1 uA typical. Always place a 100 nF decoupling capacitor within 5 mm of the VDD pins (pins 18 and 39) and a bulk 10 uF tantalum or ceramic near the MCU to suppress voltage transients during ADC sampling.
The 44-MQFP package has 0.8 mm lead pitch; PCB land pattern must comply with IPC-7351 MQFP-44 guidelines to avoid solder bridges. Place the crystal or resonator within 10 mm of pins 7-8 (OSC1/OSC2) and keep its traces short and guarded by a ground ring to minimize EMI. PORTA analog inputs (pins 1-6) should be routed away from switching digital lines, and an analog ground island connected to VSS at a single point near the MCU reduces ADC noise coupling.
Three common pitfalls when migrating from PIC16C65B to PIC16F77: (1) the configuration-word bit positions differ between OTP and Flash silicon, so the CONFIG directive in the source must be regenerated; (2) the Flash part has an internal oscillator that the OTP part lacks, requiring software changes if previously used; (3) the ICD 2/3 debug pins (RB6/RB7) are shared with PORTB on both parts, so the in-circuit serial programming header must remain accessible. Always validate timing-critical routines after migration.
Estimated: at 4 MHz oscillator the PIC16C65B-04E/PQ's PORTB and PORTC drive edges are approximately 10 ns rise/fall into 50 pF loads. For long off-board cables (>50 mm), add 33 ohm series damping resistors on RB and RC lines and ensure shielded twisted pairs for SPI clock and I2C SDA/SCL. The USART TX/RX lines (RC6/RC7) tolerate direct RS-232 transceiver interface, but adding 100 kohm pull-ups on unused RX lines prevents false-start bit detection during power-up.
Compliance Information
PIC16C65B-04E/PQ is part of Microchip's legacy OTP family and is generally not RoHS compliant; recommended only for legacy industrial/aerospace/automotive maintenance applications exempt from RoHS. Reach status is compliant per Microchip product page; no AEC-Q100 qualification is asserted for this PIC16C OTP part. For new RoHS-compliant designs, migrate to PIC16F77-I/PQ or PIC18F452-I/PQ in the same MQFP-44 footprint.
