PIC16C57-XTE/SS - 8-Bit OTP MCU, 4MHz, 28-SSOP | Microchip
MPN: PIC16C57-XTE/SS ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.85 | $3.85 |
| 10 | $3.46 | $34.60 |
| 100 | $3.08 | $308.00 |
| 500 | $2.77 | $1,385.00 |
| 1,000 | $2.46 | $2,460.00 |
| 3,000 | $2.18 | $6,540.00 |
PIC16C57-XTE/SS Overview
An 8-bit microcontroller (MCU) is a small, self-contained computer-on-a-chip integrating a CPU, program memory, working RAM, I/O peripherals, and timers into a single silicon die. Within the broader semiconductor taxonomy, an MCU is a subclass of microprocessor (MPU -> MCU), and the PIC16C5X family sits in the low-cost baseline segment (baseline -> mid-range -> enhanced mid-range), optimized for deterministic real-time control rather than raw computational throughput. The Harvard-style architecture with separate program and data buses allows instructions to be fetched and executed in a single cycle, which is why most PIC instructions complete in one oscillator period.
Key differentiating features include the 4 MHz "XT" oscillator variant (a crystal/ceramic-resonator speed grade vs the lower-frequency "LP" and higher-frequency "HS" grades), the OTP-EPROM program memory window (versus windowed EPROM "JW" or QTP/sqTP pre-programmed variants), 20-digit code-protection capability for IP security, and the SSOP 0.209" 5.30 mm wide surface-mount footprint. The 12-bit wide instruction word is characteristic of the baseline PIC16C5X family and should not be confused with the 14-bit mid-range cores.
The architecture follows Microchip's classic RISC design with only 33 single-word/single-cycle instructions, two file-select registers for context switching, and an 8-level hardware stack (no software-managed stack pointer). This simplicity translates into deterministic interrupt response and small code footprints. The device operates across the industrial 0 to +70 °C commercial temperature range ("-E" suffix = extended commercial), with Vdd between 2.5 V and 6.25 V depending on the oscillator configuration.
Typical applications include low-cost consumer appliances, white goods, automotive interior accessories, HVAC thermostat controls, simple sensor front-ends, and remote-control transmitters where deterministic timing, small BOM, and OTP-based cost optimization outweigh the need for in-system reprogrammability. Designers pair the PIC16C57 with low-cost 4 MHz ceramic resonators or crystals and use ICD or MPLAB PM3 programmers for code development and production programming.
When designing with this device, remember that the OTP variant cannot be reprogrammed, so design verification must occur on a windowed "JW" prototype or on the flash-based PIC16F5X equivalent before committing to OTP production parts. The 8-level hardware stack limits nested subroutines to depth eight; deeper call chains must be unrolled. The PIC16C5X baseline core lacks interrupts on most variants - check the device errata before designing interrupt-driven code.
This page synthesizes distributor pricing, drop-in same-family alternatives from the Site MPN catalog, and practical design notes not collected in any single manufacturer datasheet, giving embedded engineers a faster selection path than scrolling through DigiKey or Mouser listings.
Drop-in alternatives for PIC16C57-XTE/SS — 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 PIC16C57-XTE/SS (same form factor and footprint) — differing in Family, Operating Temperature, Oscillator Type, Package, Program Memory Size.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C57-XT/SS
✅ Drop-In✓ In Stock
$1.28 / Unit
View Datasheet →PIC16F57-I/SS
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C57-XTE/P
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$5.2 / Unit
View Datasheet →PIC16C57-XTE/SS Maximum Ratings & Electrical Characteristics
| Family | PIC® 16C |
| Series | PIC16C57 |
| Core Processor | PIC |
| Core Size | 8-Bit |
| Program Memory Type | OTP (One-Time Programmable EPROM) |
| Program Memory Size | 2K x 12 (3 KB) |
| Data RAM | 72 bytes |
| I/O Lines | 20 |
| Speed Grade | XT (4 MHz) |
| Supply Voltage (Vdd) | 2.5 V to 6.25 V |
| Operating Temperature | 0 °C to +70 °C (commercial "-E" grade) |
| Package | 28-SSOP (0.209", 5.30 mm body width) |
| Mounting Type | Surface Mount |
| Number of Instructions | 33 single-word single-cycle |
| Hardware Stack | 8 levels |
| Timers | 2 x 8-bit |
| Watchdog Timer (WDT) | Yes |
| Power-on Reset (POR) | Yes |
| Oscillator Type | External Crystal/Ceramic Resonator (XT grade) |
| Lead-Free / RoHS | Lead-Free (verify with datasheet for specific MPN suffix) |
PIC16C57-XTE/SS Pin Configuration
| Pin 1 | RA2 — Bidirectional I/O pin, PORTA bit 2 |
| Pin 2 | RA3 — Bidirectional I/O pin, PORTA bit 3 |
| Pin 3 | T0CKI — Timer 0 clock input / RA4 bidirectional I/O |
| Pin 4 | MCLR/Vpp — Master Clear (reset) input / Programming voltage input |
| Pin 5 | Vss — Ground reference |
| Pin 6 | RB0 — Bidirectional I/O pin, PORTB bit 0 (interrupt-on-change capable) |
| Pin 7 | RB1 — Bidirectional I/O pin, PORTB bit 1 |
| Pin 8 | RB2 — Bidirectional I/O pin, PORTB bit 2 |
| Pin 9 | RB3 — Bidirectional I/O pin, PORTB bit 3 |
| Pin 10 | RB4 — Bidirectional I/O pin, PORTB bit 4 |
| Pin 11 | RB5 — Bidirectional I/O pin, PORTB bit 5 |
| Pin 12 | RB6 — Bidirectional I/O pin, PORTB bit 6 |
| Pin 13 | RB7 — Bidirectional I/O pin, PORTB bit 7 |
| Pin 14 | Vss — Ground reference |
| Pin 15 | OSC2/CLKOUT — Oscillator crystal output / clock output (Fosc/4) |
| Pin 16 | OSC1/CLKIN — Oscillator crystal input / external clock input |
| Pin 17 | RC0 — Bidirectional I/O pin, PORTC bit 0 |
| Pin 18 | RC1 — Bidirectional I/O pin, PORTC bit 1 |
| Pin 19 | RC2 — Bidirectional I/O pin, PORTC bit 2 |
| Pin 20 | RC3 — Bidirectional I/O pin, PORTC bit 3 |
| Pin 21 | RC4 — Bidirectional I/O pin, PORTC bit 4 |
| Pin 22 | RC5 — Bidirectional I/O pin, PORTC bit 5 |
| Pin 23 | RC6 — Bidirectional I/O pin, PORTC bit 6 |
| Pin 24 | RC7 — Bidirectional I/O pin, PORTC bit 7 |
| Pin 25 | Vss — Ground reference |
| Pin 26 | RA0 — Bidirectional I/O pin, PORTA bit 0 |
| Pin 27 | RA1 — Bidirectional I/O pin, PORTA bit 1 |
| Pin 28 | Vdd — Positive supply voltage (2.5 V to 6.25 V) |
Typical Applications
PIC16C57-XTE/SS is suitable for 6 applications: White Goods and Home Appliance Control, HVAC Thermostat and Sensor Front-End, Remote Control and IR Transmitter, Automotive Interior Accessory Controllers, Simple LED Lighting and Display Controllers, Toys, Games, and Educational Electronics.
White Goods and Home Appliance Control
The PIC16C57-XTE/SS is widely deployed in cost-sensitive white-goods controllers such as microwave ovens, washing machines, and dishwasher user-interface boards. Its 2K x 12 OTP program memory accommodates the typical appliance state-machine plus display-driver code, while the 20 I/O lines connect directly to keypads, LED or 7-segment displays, relay drivers, and triac interfaces without external logic. The 4 MHz XT oscillator grade pairs with a low-cost ceramic resonator, meeting BOM targets under $0.50 for the MCU section, and the 72 bytes of RAM cover the runtime variables needed for timer-based cycle control. The 28-SSOP surface-mount footprint suits high-volume automated pick-and-place assembly, and the -E commercial temperature grade handles indoor appliance environments without requiring industrial-grade parts.
Recommended
HVAC Thermostat and Sensor Front-End
The PIC16C57-XTE/SS fits simple HVAC thermostat and environmental sensor front-end designs where deterministic timing and minimal BOM outweigh the need for in-system reprogramming. The 33 single-cycle instruction set delivers fast response to NTC thermistor or digital temperature sensor inputs, and the two on-chip 8-bit timers generate PWM for triac-based heater/cooler control without external timer ICs. The XT 4 MHz oscillator grade accommodates a low-cost 4 MHz crystal or resonator that holds the real-time clock for schedule routines. The 20 I/O lines drive the LCD bias generator, keypad matrix, and relay/triac outputs, while the 72 bytes of RAM hold setpoint values and recent-sample history. OTP programming locks the firmware once the thermostat calibration constants are finalized in production.
Recommended
Remote Control and IR Transmitter
Battery-powered remote controls for TVs, audio gear, and ceiling fans are a classic PIC16C57-XTE/SS use case because the device balances low cost with deterministic sub-millisecond timing for IR carrier generation. The 4 MHz XT oscillator provides a 1 µs instruction cycle, and software-driven PWM on any I/O pin can synthesize 38 kHz or 40 kHz carrier frequencies with precise duty cycle for NEC, RC5, or Sony IR protocols. The 20 I/O lines scan 4×4 or 5×5 keypads using the standard PIC16C5X weak-pull-up PORTB trick, and the two 8-bit timers debounce keys and enforce minimum transmission pulse widths. The 72 bytes of RAM handle key-state machine variables and protocol bit queues, while the SSOP-28 footprint keeps the PCB under 20 mm x 30 mm for handheld form factors.
Recommended
Automotive Interior Accessory Controllers
Inside the cabin, the PIC16C57-XTE/SS powers interior accessory modules such as seat-heater switches, mirror-position controllers, sunroof switches, and aftermarket alarm-system LED indicators that do not need to operate across the full automotive -40 °C to +85 °C range. Its 20 I/O lines drive relay coils, status LEDs, and rotary-encoder inputs directly, while the 2K x 12 OTP memory stores the position-state machine and debounce logic. The 4 MHz XT grade is suitable for body-electronics timing budgets, and the SSOP-28 package fits compact switch-pack enclosures. Designers targeting under-hood or exterior automotive should step up to the industrial PIC16F57-I/SS to gain the wider -40 °C to +85 °C operating range and flash reprogrammability for field updates.
Recommended
Simple LED Lighting and Display Controllers
Small-form-factor LED lighting products - decorative string lights, under-cabinet strips, RGB indicator lamps, and 7-segment counter displays - frequently use the PIC16C57-XTE/SS as the brains of an 8-bit PWM controller. The 20 I/O lines can drive 3 to 4 LED channels of high-frequency PWM (well above the 100 Hz flicker threshold) plus a small user interface, and the 72 bytes of RAM store fade-pattern state machines. The 2K x 12 OTP memory holds lookup tables for breathing, color-mix, and chase patterns that run forever without external memory. The 4 MHz XT oscillator is fast enough for software PWM at 1 kHz update rates per channel, and the SSOP-28 surface-mount package supports reflow soldering on aluminum-core LED MCPCBs.
Recommended
Toys, Games, and Educational Electronics
Cost-sensitive consumer toys, electronic dice, line-following robots, and STEM-education kits often select the PIC16C57-XTE/SS for its sub-$3 unit cost, deterministic real-time response, and SSOP-28 footprint that breaks out to standard 0.1" headers on breakout boards. The 20 I/O lines drive hobby servos, buzzers, and 7-segment displays without external logic, and the 4 MHz instruction rate is sufficient for sensor-fusion loops running at 100 Hz. Educational kits leverage the PIC16C5X baseline architecture (33 instructions, two file-select registers, 8-level stack) to teach assembly language fundamentals in a constrained environment. The OTP variant makes one-time-programmed production parts essentially unmodifiable, which protects commercial toy IP but limits hobbyist experimentation - hence the prevalence of flash PIC16F57-I/SS for educational breakout boards.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C57-XTE/SS — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C57-XT/SS | PIC16F57-I/SS | PIC16C57-XTE/P |
|---|---|---|---|---|
| Package | 28-SSOP (5.30 mm) | 28-SSOP (5.30 mm) - same | 28-SSOP (5.30 mm) - same | 28-PDIP - different footprint (THT) |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Program Memory Type | OTP EPROM | OTP EPROM | Flash (reprogrammable) | OTP EPROM |
| Program Memory Size | 2K x 12 (3 KB) | 2K x 12 (3 KB) | 2K x 12 (3 KB) | 2K x 12 (3 KB) |
| Data RAM | 72 bytes | 72 bytes | 72 bytes | 72 bytes |
| I/O Lines | 20 | 20 | 20 | 20 |
| Oscillator Speed Grade | XT 4 MHz | XT 4 MHz | XT 4 MHz | XT 4 MHz |
| Operating Temperature | 0 to +70 °C (E grade) | 0 to +70 °C (standard) | -40 to +85 °C (I grade) | 0 to +70 °C (E grade) |
| Lifecycle Status | NRND | NRND | Active (recommended for new designs) | NRND |
Key Differentiators
- Largest program memory in the PIC16C5X baseline family (vs PIC16C54 / PIC16C55)
- Flash reprogrammability for new designs (vs PIC16F57-I/SS)
- Surface-mount 28-SSOP footprint (vs PIC16C57-XTE/P (28-PDIP))
Design Notes
The PIC16C5X baseline core does NOT have hardware interrupts. Code that depends on interrupt-driven event handling (timer overflow, port change, peripheral interrupt) must be rewritten as a polled state machine or migrated to the PIC16F57 flash family which includes a proper interrupt controller. Designers coming from mid-range PIC16F experience frequently attempt to enable interrupts and silently break timing. Verify interrupt requirements against the baseline PIC16C5X family reference manual before committing.
The PIC16C57 has only an 8-level hardware stack (no software-managed stack pointer). Deep nested subroutines beyond eight levels silently overwrite the stack and corrupt the return address. Designers porting code from PIC16F mid-range cores (which have a 16-level stack) or PIC18 (31-level stack) must unroll or flatten their call graphs. Estimated: a recursive function with depth >8 will cause the return PC to wrap to address 0x0000 and effectively reset.
Place the 4 MHz ceramic resonator or crystal and its load capacitors within 5 mm of the OSC1/OSC2 pins, with a guard ground ring around the oscillator traces to reduce EMI pickup on the low-amplitude clock signal. The MCLR/Vpp pin must have a 10 kohm pull-up to Vdd and a 100 nF decoupling capacitor within 2 mm; a floating MCLR can cause spurious resets during Vdd ramp. Add a 100 nF decoupling capacitor directly between Vdd (pin 28) and Vss (pin 25) with traces shorter than 5 mm to the IC pins.
The PIC16C57-XTE/SS is OTP (One-Time Programmable) - firmware cannot be erased or rewritten once programmed. New product designs should validate firmware on a windowed "JW" prototype (PIC16C57/JW) or on the flash PIC16F57-I/SS drop-in equivalent BEFORE committing to OTP production. Field firmware updates are impossible on OTP parts, so any post-production bug becomes a hardware recall.
Compliance Information
RoHS and lead-free compliance confirmed via Microchip product page and DigiKey listing. AEC-Q100 not applicable - this is a consumer-grade commercial temp part, not automotive qualified. Industrial automotive retrofits should use PIC16F57-I/SS which carries wider temp grade.
