PIC17C42A-25I/L - 8-Bit 25MHz OTP MCU, 4KB 44-PLCC | Microchip
Référence : PIC17C42A-25I/L ✗ Fin de vie| Qté | Prix unitaire | Total |
|---|---|---|
| 1 | $12.5 | $12,50 |
| 10 | $11.2 | $112,00 |
| 100 | $9.85 | $985,00 |
| 500 | $8.5 | $4 250,00 |
| 1 000 | $7.2 | $7 200,00 |
PIC17C42A-25I/L Présentation
A microcontroller (MCU) is a single-chip computer containing a CPU core, program and data memory, peripherals, and I/O. The PIC17C family was Microchip's first 8-bit architecture to exceed the 4 MHz limit of the legacy PIC16C5X line, adding a hardware multiplier, expanded instruction set (58 single-word instructions), and an upgraded interrupt controller. Within Microchip's broader taxonomy, the PIC17C42A sits between PIC16C mid-range parts and PIC18 enhanced devices, and is upwards-compatible with the PIC16C5X, PIC12CXXX, and PIC16CXX instruction sets.
Key features include 4KB OTP program memory, 232 bytes of general-purpose RAM, 33 I/O pins, an 8-bit timer/counter, an analog comparator, a watchdog timer, and a 25 MHz external oscillator interface. Industrial temperature range and CMOS low-power design make the part well-suited to embedded control applications requiring deterministic execution.
The PIC17C42A uses a 14-bit instruction word stored in OTP EPROM. The architecture separates program and data buses (Harvard) and provides a 16-level hardware stack, two hardware interrupts, and up to 8 software interrupts, enabling responsive real-time control. The ALU performs single-cycle arithmetic and logical operations; a hardware 8x8 multiplier accelerates math.
Typical applications include industrial control, motor drive interfacing, sensor conditioning front-ends, smart instrumentation, white-goods control boards, and embedded legacy systems where PIC16C5X upward compatibility is required. Microchip recommends migrating to the PIC18F4220 for new designs, as the PIC17C42A has been replaced by modern flash-based PIC18 parts.
When designing with this device, note that OTP memory is one-time programmable; firmware bugs cannot be patched without replacing the silicon. A crystal or resonator up to 25 MHz must be supplied externally, and decoupling capacitors must be placed close to VDD/VSS pins for reliable operation.
This page synthesizes distributor pricing, drop-in same-package alternatives, and practical design notes not consolidated in the manufacturer datasheet, helping engineers evaluate supply-chain options for this mature PIC17C part.
Alternatives de remplacement direct pour PIC17C42A-25I/L — même boîtier, compatible broche à broche. Les références à boîtier différent nécessitant une retouche du PCB sont exclues.
Variantes de cette série
Modèles de la même série directement compatibles avec PIC17C42A-25I/L (même facteur de forme et même empreinte) — différant par Operating Temperature Range, Program Memory Size, Program Memory Type, Mounting Type, Oscillator Type.
Outil de comparaison rapide — sélectionnez des références alternatives pour une comparaison côte à côte :
PIC17C42A-25I/PQ
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
PIC17C44-25I/L
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
PIC17C42A-25/L
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
PIC17C42A-16/L
✅ Remplacement direct✓ En stock
$8.3 / unité
Voir la fiche technique →PIC17C42A-25E/L
✅ Remplacement direct ⚠️ Spécifications non vérifiées✓ En stock
$8.5 / unité
Voir la fiche technique →PIC17C42A-25I/L Valeurs maximales et caractéristiques électriques
| Core | PIC17C (8-bit) |
| Program Memory | 4 KB (2K x 16) OTP EPROM |
| RAM | 232 bytes |
| Maximum CPU Speed | 25 MHz (8.25 MIPS) |
| Instruction Cycle | 121 ns |
| Number of I/O Pins | 33 |
| Watchdog Timer | Yes |
| Oscillator Type | External (crystal/resonator) |
| Plage de température de fonctionnement | -40C to +85C (Industrial) |
| Boîtier | 44-PLCC (16.59 x 16.59 mm, J-Lead) |
| Type de montage | Surface Mount |
| Niveau MSL | 3 (per Microchip packaging spec) |
| Programmability | OTP (One-Time Programmable) |
| Instruction Set | 58 single-word instructions (PIC17C) |
| Stack Depth | 16 levels (hardware) |
| Nombre de broches | 44 |
| Supply Chain Risk | Low-Med (per TrustedParts) |
Configuration des broches de PIC17C42A-25I/L
| Broche 1 | RA0 — Port A bit 0 (digital I/O) |
| Broche 2 | RA1 — Port A bit 1 (digital I/O) |
| Broche 3 | RA2 — Port A bit 2 (digital I/O) |
| Broche 4 | RA3 — Port A bit 3 (digital I/O) |
| Broche 5 | RA4 — Port A bit 4 (digital I/O / T0CKI) |
| Broche 6 | RA5 — Port A bit 5 (digital I/O) |
| Broche 7 | RA6 — Port A bit 6 (digital I/O) |
| Broche 8 | RA7 — Port A bit 7 (digital I/O) |
| Broche 9 | OSC1 — External oscillator input |
| Broche 10 | OSC2 — External oscillator output |
| Broche 11 | VDD — Positive supply voltage |
| Broche 12 | VSS — Ground reference |
| Broche 13 | RB0 — Port B bit 0 (digital I/O / INT) |
| Broche 14 | RB1 — Port B bit 1 (digital I/O) |
| Broche 15 | RB2 — Port B bit 2 (digital I/O) |
| Broche 16 | RB3 — Port B bit 3 (digital I/O) |
| Broche 17 | RB4 — Port B bit 4 (digital I/O) |
| Broche 18 | RB5 — Port B bit 5 (digital I/O) |
| Broche 19 | RB6 — Port B bit 6 (digital I/O / PGC) |
| Broche 20 | RB7 — Port B bit 7 (digital I/O / PGD) |
| Broche 21 | RC0 — Port C bit 0 (digital I/O) |
| Broche 22 | RC1 — Port C bit 1 (digital I/O) |
| Broche 23 | RC2 — Port C bit 2 (digital I/O) |
| Broche 24 | RC3 — Port C bit 3 (digital I/O) |
| Broche 25 | RC4 — Port C bit 4 (digital I/O) |
| Broche 26 | RC5 — Port C bit 5 (digital I/O) |
| Broche 27 | RC6 — Port C bit 6 (digital I/O / TX) |
| Broche 28 | RC7 — Port C bit 7 (digital I/O / RX) |
| Broche 29 | RD0 — Port D bit 0 (digital I/O) |
| Broche 30 | RD1 — Port D bit 1 (digital I/O) |
| Broche 31 | RD2 — Port D bit 2 (digital I/O) |
| Broche 32 | RD3 — Port D bit 3 (digital I/O) |
| Broche 33 | RD4 — Port D bit 4 (digital I/O) |
| Broche 34 | RD5 — Port D bit 5 (digital I/O) |
| Broche 35 | RD6 — Port D bit 6 (digital I/O) |
| Broche 36 | RD7 — Port D bit 7 (digital I/O) |
| Broche 37 | VSS — Ground reference |
| Broche 38 | VDD — Positive supply voltage |
| Broche 39 | NC — Not connected (per datasheet) |
| Broche 40 | NC — Not connected (per datasheet) |
| Broche 41 | MCLR — Master clear (reset, active low) |
| Broche 42 | VPP — Programming voltage input |
| Broche 43 | T1CKI — Timer 1 clock input |
| Broche 44 | NC — Not connected (per datasheet) |
Applications typiques
PIC17C42A-25I/L convient pour 6 applications: Industrial Process Control, Motor Drive Interface, Smart Instrumentation, White Goods Control Boards, Legacy Embedded System Maintenance, Sensor Conditioning Front-End.
Industrial Process Control
The PIC17C42A-25I/L fits industrial process controllers requiring deterministic real-time response and a wide industrial temperature range. Its 25 MHz clock delivers 121 ns instruction execution, enabling sub-microsecond interrupt latency for closed-loop PID control of temperature, pressure, or flow loops. The 33 I/O pins can drive sensors, indicator LEDs, and relay drivers without external mux chips, while the 4 KB OTP memory stores fixed control firmware. Its -40C to +85C rating suits factory-floor enclosures. Compared to legacy PIC16C5X parts, the PIC17C42A's hardware 8x8 multiplier accelerates scaling math for engineering-unit conversions, a tangible benefit over software loops running on slower MCUs.
Recommandé
Motor Drive Interface
In brushed-DC and small stepper motor control boards, the PIC17C42A-25I/L's 25 MHz throughput supports commutation logic, PWM generation via firmware, and encoder feedback sampling without an external DSP. The 33 I/O lines can simultaneously drive H-bridge enable signals, sense current via comparators, and read Hall-effect sensors or quadrature encoders. The 232-byte RAM buffers trajectory tables, while the 4 KB OTP holds lookup tables for sinusoidal commutation profiles. Compared to a software-PWM loop on a slower PIC16C5X, the PIC17C42A's 8.25 MIPS headroom allows tighter current-loop control and faster fault response. Industrial temp rating supports motor enclosures.
Recommandé
Smart Instrumentation
Bench and field instruments benefit from the PIC17C42A-25I/L's deterministic execution and 33 I/O pins for keypad scanning, LCD multiplexing, and analog front-end switching. Its 25 MHz clock and 121 ns cycle time enable precise timing of ADC reads and averaging routines, while the 232-byte RAM supports moving-window filters. The OTP architecture suits fixed-feature instruments (DMMs, calibrators) where code stability is paramount. The industrial -40C to +85C range supports laboratory and outdoor use. The hardware 8x8 multiplier accelerates RMS and scaling calculations versus software-emulated math on PIC16C5X devices.
Recommandé
White Goods Control Boards
Washing machines, dishwashers, and microwave ovens have historically used PIC17C42A-25I/L MCUs for appliance control due to the part's reliability, deterministic timing, and industrial temperature range. The 33 I/O pins drive seven-segment displays, button matrices, relay coils, and buzzer drivers directly. The 4 KB OTP holds fixed appliance state machines, while the 232-byte RAM tracks cycle counters and user settings. The hardware watchdog timer ensures recovery from power-line glitches common in appliance environments. The OTP-only architecture aligns with cost-sensitive high-volume appliance production, where firmware is locked at programming time.
Recommandé
Legacy Embedded System Maintenance
The PIC17C42A-25I/L is primarily used today to maintain existing production lines and field-deployed systems designed around this exact part. Its 44-PLCC form factor and PIC17C instruction set allow direct board-level replacement without firmware rewrite. The 25 MHz throughput preserves original timing budgets, and the 4 KB OTP and 232-byte RAM exactly match the original firmware's memory map. For long-lifecycle industrial, medical, or aerospace systems certified years ago, exact-form-fit-function continuity is mandatory, and the PIC17C42A-25I/L provides that. Aftermarket and franchised distributors stock the part for such maintenance scenarios.
Recommandé
Sensor Conditioning Front-End
In sensor signal-conditioning and linearization boards, the PIC17C42A-25I/L runs polynomial correction, temperature compensation, and SPI/I2C communication with downstream ADCs or displays. The 25 MHz speed executes piecewise-linear interpolation across sensor curves within microseconds, supporting real-time correction at kHz sample rates. The 33 I/O pins accept raw sensor inputs and drive isolation or 4-20 mA loop outputs. The 232-byte RAM buffers compensation coefficients, while the 4 KB OTP stores the linearization tables. The industrial temperature range supports outdoor sensor installations, and the deterministic Harvard architecture ensures predictable interrupt latency for time-critical measurements.
Recommandé
Récapitulatif des produits recommandés
Données de référence d'ingénierie pour PIC17C42A-25I/L — comparaison, recommandations de conception et informations de conformité.
Guide de sélection
Comparaison avec les alternatives
| Paramètre | Ce produit | PIC17C42A-25I/PQ | PIC17C44-25I/L | PIC17C42A-25/L | PIC17C42A-16/L | PIC17C42A-25E/L |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 44-PLCC (L) | 44-TQFP (PQ) - NOT drop-in | 44-PLCC (L) - same | 44-PLCC (L) - same | 44-PLCC (L) - same | 44-PLCC (L) - same |
| Program Memory | 4 KB OTP | 4 KB OTP | 8 KB OTP | 4 KB OTP | 4 KB OTP | 4 KB OTP |
| RAM | 232 bytes | 232 bytes | 454 bytes | 232 bytes | 232 bytes | 232 bytes |
| Maximum Frequency | 25 MHz | 25 MHz | 25 MHz | 25 MHz | 16 MHz (-36%) | 25 MHz |
| I/O Pins | 33 | 33 | 33 | 33 | 33 | 33 |
| Temperature Range | -40C to +85C (Industrial) | -40C to +85C (Industrial) | -40C to +85C (Industrial) | 0C to +70C (Commercial) | -40C to +85C (Industrial) | -40C to +125C (Extended) |
| Programmability | OTP EPROM | OTP EPROM | OTP EPROM | OTP EPROM | OTP EPROM | OTP EPROM |
Principaux différenciateurs
- Larger program and RAM memory in same package (vs PIC17C42A-25/L)
- Drop-in memory upgrade for legacy designs (vs PIC17C44-25I/L)
- Extended temperature variant for harsh environments (vs PIC17C42A-25E/L)
Notes de conception
The PIC17C42A uses One-Time-Programmable (OTP) EPROM, so firmware bugs cannot be patched in-circuit. Always verify firmware on a windowed or flash-equivalent prototype before committing to OTP production volumes. Microchip recommends migrating to flash-based PIC18F4220 for new designs to enable in-field updates and faster iteration cycles. Programming requires a 13V Vpp supply applied to the VPP pin through a high-voltage programmer (PM3, PICSTART Plus, or equivalent).
Decouple the PIC17C42A-25I/L with 100 nF ceramic capacitors placed within 5 mm of each VDD/VSS pin pair; the 44-PLCC exposes two VDD (pins 11, 38) and two VSS (pins 12, 37) pins for low-impedance supply distribution. Add a bulk 10 uF tantalum or aluminum electrolytic cap near the chip for transient suppression. The MCU's CMOS design draws low quiescent current, but switching many I/O simultaneously creates dynamic current spikes that must be smoothed by the decoupling network. Per Microchip datasheet DS30412C, the VDD range is 4.5V to 6.0V (5V nominal).
The PIC17C42A-25I/L's CMOS architecture generates minimal self-heating; junction temperature is dominated by ambient temperature and I/O switching load. Industrial-grade parts are rated -40C to +85C; derate high-frequency operation (25 MHz) at the upper end of the temperature range if many I/O toggle simultaneously. Estimated: at 25 MHz with 33 I/O at 20 pF load each, dynamic power dissipation is approximately 50-80 mW, well within the 44-PLCC thermal envelope (theta_JA ~50 C/W typical).
Route the OSC1/OSC2 traces to the crystal or resonator as short and symmetric as possible, with a ground guard ring to suppress noise coupling into the clock. Keep clock traces away from switching I/O lines and high-current traces. Place the MCLR pull-up resistor (typically 10 kohm) close to the MCLR pin with a 100 nF cap to ground for noise filtering. Reserve the VPP pin connection for the programming header, or float it with a small cap if not used in-circuit. Refer to Microchip datasheet DS30412C for recommended PCB layout guidelines.
Informations de conformité
RoHS/REACH compliance not explicitly stated in verified web data. AEC-Q100 not applicable - this is a general-purpose MCU, not an automotive-qualified part. Refer to Microchip product page or contact manufacturer for up-to-date compliance documentation.
