PIC17C42A-33/PT - 8-Bit 33MHz OTP MCU 4KB | Microchip
MPN: PIC17C42A-33/PT ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $18.95 | $18.95 |
| 10 | $16.42 | $164.20 |
| 100 | $13.85 | $1,385.00 |
| 500 | $11.2 | $5,600.00 |
| 1,000 | $9.65 | $9,650.00 |
PIC17C42A-33/PT Overview
An 8-bit microcontroller is a microprocessor optimized for embedded control, integrating CPU core, program memory, data RAM, and peripherals on a single die. Within the embedded hierarchy it sits as a small-form-factor, deterministic alternative to 16- and 32-bit MCUs and to microprocessors that lack on-chip memory. Microcontrollers (MCUs) belong to the broader category of microprocessors and ultimately to semiconductors and integrated circuits. The PIC17C family extends the PIC16C5X/PIC16CXX instruction set upward, providing PIC16C source-level compatibility while adding hardware multipliers, multiple interrupt vectors, and a wider 16-bit instruction word.
Key features include a maximum clock input of 33 MHz, an instruction cycle of 121 ns at that frequency, four crystal oscillator modes (LP, XT, RC, HS), and a wide 4.5 V to 5.5 V commercial operating voltage. Peripheral highlights are an 8-bit timer/counter with 8-bit prescaler, a 16-bit timer/counter with 4-bit prescaler, a watchdog timer with on-chip RC oscillator, capture/compare/PWM module, dual analog comparators, and a USART with on-chip baud-rate generator.
Typical applications include industrial control logic, instrumentation front-ends, automotive body controllers, motor-drive interface boards, smart sensor hubs, and legacy PIC16C system upgrades that need extra throughput and pins without retooling the codebase.
Design consideration: OTP memory is one-time programmable; for development use the PIC17C42A-33/PT windowed CERDIP variant or an equivalent flash device such as PIC18F4220.
This page aggregates pricing, drop-in compatible TQFP-44 alternatives, and engineering guidance drawn from manufacturer datasheets, application notes, and distributor listings.
Drop-in alternatives for PIC17C42A-33/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 PIC17C42A-33/PT (same form factor and footprint) — differing in Core Architecture, Package, Program Memory Type, Mounting Type, Program Memory Size.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC17C42A-25/PT
✅ Drop-In✓ In Stock
$5.55 / Unit
View Datasheet →PIC17C42A-33E/PT
✅ Drop-In✓ In Stock
$8.5 / Unit
View Datasheet →PIC17C42AT-33I/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC17C43-33I/PT
✅ Drop-In✓ In Stock
$8.85 / Unit
View Datasheet →PIC18F4220-I/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC17C42A-33/PT Maximum Ratings & Electrical Characteristics
| Core | PIC 8-bit RISC |
| Core Architecture | PIC17C |
| Program Memory Type | OTP EPROM |
| Program Memory Size | 4 KB (2K x 16) |
| RAM Size | 232 bytes |
| Data EEPROM | Not present |
| Maximum Clock Frequency | 33 MHz |
| Instruction Cycle | 121 ns (8.25 MIPS) |
| Operating Voltage | 4.5 V to 5.5 V |
| I/O Pins | 33 |
| Package | TQFP-44 (PT) |
| Mounting Type | Surface Mount |
| Operating Temperature | 0C to +70C (Commercial) |
| Instruction Set | 58 single-word instructions |
| Peripherals | 8-bit Timer, 16-bit Timer, WDT, USART, CCP, 2x Analog Comparator |
| Suggested Upgrade | PIC18F4220 |
PIC17C42A-33/PT Pin Configuration
| Pin 1 | MCLR — Master clear (reset) input, active low |
| Pin 2 | VDD — Positive supply voltage |
| Pin 3 | RA0 — Port A bit 0 (digital I/O) |
| Pin 4 | VDD — Positive supply voltage |
| Pin 5 | RA1 — Port A bit 1 (digital I/O) |
| Pin 6 | RA2 — Port A bit 2 (digital I/O) |
| Pin 7 | RA3 — Port A bit 3 (digital I/O) |
| Pin 8 | RA4 — Port A bit 4 (digital I/O, open-drain) |
| Pin 9 | RA5 — Port A bit 5 (digital I/O) |
| Pin 10 | VSS — Ground reference |
| Pin 11 | OSC1 — Oscillator input / external clock |
| Pin 12 | OSC2 — Oscillator output |
| Pin 13 | RC0 — Port C bit 0 (digital I/O / T0CKI) |
| Pin 14 | RC1 — Port C bit 1 (digital I/O / CCP2) |
| Pin 15 | RC2 — Port C bit 2 (digital I/O / CCP1) |
| Pin 16 | RC3 — Port C bit 3 (digital I/O) |
| Pin 17 | RC4 — Port C bit 4 (digital I/O) |
| Pin 18 | RC5 — Port C bit 5 (digital I/O) |
| Pin 19 | RC6 — Port C bit 6 (digital I/O / TX) |
| Pin 20 | RC7 — Port C bit 7 (digital I/O / RX) |
| Pin 21 | RB0 — Port B bit 0 (digital I/O / INT) |
| Pin 22 | RB1 — Port B bit 1 (digital I/O) |
| Pin 23 | RB2 — Port B bit 2 (digital I/O) |
| Pin 24 | RB3 — Port B bit 3 (digital I/O) |
| Pin 25 | RB4 — Port B bit 4 (digital I/O) |
| Pin 26 | RB5 — Port B bit 5 (digital I/O) |
| Pin 27 | RB6 — Port B bit 6 (digital I/O / PGC) |
| Pin 28 | RB7 — Port B bit 7 (digital I/O / PGD) |
| Pin 29 | VSS — Ground reference |
| Pin 30 | RD0 — Port D bit 0 (digital I/O) |
| Pin 31 | RD1 — Port D bit 1 (digital I/O) |
| Pin 32 | RD2 — Port D bit 2 (digital I/O) |
| Pin 33 | RD3 — Port D bit 3 (digital I/O) |
| Pin 34 | RD4 — Port D bit 4 (digital I/O) |
| Pin 35 | RD5 — Port D bit 5 (digital I/O) |
| Pin 36 | RD6 — Port D bit 6 (digital I/O) |
| Pin 37 | RD7 — Port D bit 7 (digital I/O) |
| Pin 38 | VSS — Ground reference |
| Pin 39 | VDD — Positive supply voltage |
| Pin 40 | NC — Not connected (per datasheet) |
| 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
PIC17C42A-33/PT is suitable for 6 applications: Industrial Control Logic, Legacy PIC16C System Migration, Automotive Body Controllers, Instrumentation Front-Ends, Motor Drive Interface Boards, Smart Sensor Hubs.
Industrial Control Logic
The PIC17C42A-33/PT's 8.25 MIPS throughput and 33 digital I/O lines make it a strong fit for industrial control boards driving relays, solenoids, and indicator panels. Its 121 ns instruction cycle closes a deterministic PID control loop within microseconds, while the 232-byte SRAM is sufficient to hold setpoint, error, and integrator terms. Industrial designers value the part's wide 4.5 V to 5.5 V supply tolerance, which tolerates unregulated 5 V rails typical of factory floor power. Recommended companions include the ULN2003A relay driver for output expansion and the 24LC256 EEPROM for non-volatile parameter storage.
Recommended
Legacy PIC16C System Migration
When a PIC16C5X or PIC16CXX-based board must scale up in code size or pin count without rewriting the assembly codebase, the PIC17C42A-33/PT is the documented upward-compatible step. It shares the PIC16C source-level compatibility, adds an 8-bit hardware multiplier, multiple interrupt vectors, and a wider 16-bit instruction word, while keeping the same 33 MHz maximum clock and a familiar oscillator architecture. This makes it ideal for manufacturers maintaining field-deployed PIC16C products that need to add features. For new development Microchip recommends the modern flash-based PIC18F4220 instead.
Recommended
Automotive Body Controllers
Body-electronics modules such as door-lock controllers, window lifters, and lighting drivers benefit from the PIC17C42A-33/PT's combination of 33 MHz throughput, hardware PWM via the CCP module, and dual analog comparators for current sensing. The 8-bit timer and 16-bit timer with prescaler allow accurate PWM generation for LED dimming and motor speed control, while the USART simplifies body-CAN gateway integration via an external MCP2515. The automotive-grade -40C to +125C variant PIC17C42A-33E/PT is the appropriate part for under-hood environments, while the commercial PIC17C42A-33/PT serves cabin electronics.
Recommended
Instrumentation Front-Ends
Bench-top instruments and panel meters use the PIC17C42A-33/PT to digitize analog inputs, drive alphanumeric LCDs, and scan keypads. The integrated dual analog comparator allows window-comparator threshold detection without an external op-amp stage, and the USART with on-chip baud-rate generator streams measured data to a host PC at 9600-115200 bps. The 121 ns instruction cycle samples the analog comparator on every cycle, enabling sub-microsecond event capture for instrumentation-grade timing.
Recommended
Motor Drive Interface Boards
Stepper and DC motor controllers built around the PIC17C42A-33/PT leverage its hardware CCP module to generate accurate step pulses and direction signals. The 16-bit timer with 4-bit prescaler delivers the precise timing required for microstepping algorithms, while 33 I/O pins drive multiple axis drivers in parallel. The watchdog timer with on-chip RC oscillator catches software lockups in unattended motor systems, automatically resetting the controller to a safe state.
Recommended
Smart Sensor Hubs
Distributed sensor networks use the PIC17C42A-33/PT as a low-cost hub microcontroller that aggregates analog and digital sensor data and forwards it over the on-chip USART or a software bit-banged I2C/SPI bus. The 4 KB OTP program memory accommodates sensor-fusion algorithms and protocol stacks, while 232 bytes of SRAM buffers transient measurements. The dual analog comparators enable direct threshold-based alarm generation without burdening the CPU.
Recommended
Recommended Products Summary
Engineering reference data for PIC17C42A-33/PT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC17C42A-25/PT | PIC17C42A-33E/PT | PIC17C42AT-33I/PT | PIC17C43-33I/PT | PIC18F4220-I/PT |
|---|---|---|---|---|---|---|
| Package | TQFP-44 (PT) | TQFP-44 (PT) - same | TQFP-44 (PT) - same | TQFP-44 (PT) - same | TQFP-44 (PT) - same | TQFP-44 (PT) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Maximum Clock | 33 MHz | 25 MHz | 33 MHz | 33 MHz | 33 MHz | 40 MHz |
| Program Memory | 4 KB OTP | 4 KB OTP | 4 KB OTP | 4 KB OTP | 8 KB OTP | 4 KB Flash |
| RAM | 232 bytes | 232 bytes | 232 bytes | 232 bytes | 256 bytes | 512 bytes |
| Operating Voltage | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 3.0 V to 5.5 V | 2.0 V to 5.5 V |
| Operating Temperature | 0C to +70C | 0C to +70C | -40C to +125C | -40C to +85C | -40C to +85C | -40C to +85C |
| Memory Type | OTP EPROM | OTP EPROM | OTP EPROM | OTP EPROM | OTP EPROM | Flash |
| Lifecycle | Obsolete | Obsolete | Obsolete | Obsolete | Obsolete | Active |
Key Differentiators
- Highest-spec PIC17C42A variant in production-grade TQFP-44 (vs PIC17C42A-25/PT)
- Extended -40C to +125C automotive temperature grade (vs PIC17C42A-33E/PT)
- Double program memory and on-chip data EEPROM (vs PIC17C43-33I/PT)
- Flash memory and active production status (vs PIC18F4220-I/PT)
Design Notes
OTP EPROM on PIC17C42A-33/PT can be programmed only once; verify firmware on the PIC17C42A-33/P or PIC17C42A-33E/PT windowed CERDIP variants before committing to surface-mount programming. MCLR must be tied through a 10 kohm pull-up to VDD; leaving MCLR floating allows spurious resets. Decouple VDD/VSS pairs with 0.1 uF ceramic as close to the IC as possible to suppress switching transients.
PIC17C42A-33/PT draws up to 50 mA at 33 MHz with all 33 I/O lines driving capacitive loads. Estimated: with VDD=5 V and 50 mA load, the part dissipates approximately 0.25 W. A 4-layer PCB with a small ground pour is sufficient; however, on a 2-layer board add a copper ground flood under the TQFP-44 footprint to keep the thermal rise below 15 C above ambient.
Place the oscillator crystal or resonator within 0.5 inches of OSC1 (pin 11) and OSC2 (pin 12); keep the trace pair short, symmetric, and guarded by a ground pour to minimize radiated EMI. For HS mode above 25 MHz, add a series resistor matched to the crystal's load specification; consult the PIC17C4x datasheet oscillator section for the exact RC network. Route USART lines (RC6/RC7) away from high-current switching traces.
Estimated: at VDD=5 V and 50 mA active current, the TQFP-44 package dissipates about 0.25 W. With a theta_JA of approximately 50 C/W on a 2-layer board, junction temperature rises roughly 12 C above ambient - well within the 0C to +70C commercial rating. In enclosed industrial cabinets, ensure ambient does not exceed 60 C to maintain the safety margin.
Compliance Information
Compliance flags not present in the verified distributor or manufacturer snippets; recommend confirming with the original Microchip datasheet or contacting Microchip support for the latest RoHS/REACH certificate before volume production.
