PIC16C57-XT/SS - 8-Bit EPROM MCU 4MHz 28-SSOP | Microchip
MPN: PIC16C57-XT/SS ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.02 | $2.02 |
| 10 | $1.85 | $18.50 |
| 100 | $1.62 | $162.00 |
| 500 | $1.42 | $710.00 |
| 1,000 | $1.28 | $1,280.00 |
PIC16C57-XT/SS Overview
What is a PIC16C5X microcontroller? The PIC16C5X is a family of low-cost, high-performance, 8-bit fully static EPROM/ROM-based CMOS microcontrollers that deliver an order-of-magnitude higher performance than competing 8-bit microcontrollers in the same price category. The 12-bit wide instructions are highly symmetrical, producing a 2:1 code compression over other 8-bit MCUs in its class. These devices belong to the broader category of microcontrollers -> 8-bit MCUs -> EPROM-based MCUs -> embedded controllers -> semiconductors, and are commonly deployed in cost-sensitive, space-constrained embedded designs.
Key features include 12-bit wide instructions, an 8-bit wide data path, seven or eight special function hardware registers, a two-level deep hardware stack, and direct, indirect, and relative addressing modes for both data and instructions. An 8-bit real-time clock/counter (TMR0) with a programmable prescaler handles timing events. The 'XT' suffix denotes a 4 MHz external crystal/oscillator speed option, and 'SS' denotes the 28-pin SSOP (5.30 mm body width) package.
Technically, the PIC16C57-XT/SS uses a RISC architecture with a 12-bit instruction word and an 8-bit data path. The OTP EPROM program memory enables prototype and pre-production programming before committing to a ROM mask, while the SSOP package is suited to surface-mount manufacturing.
Typical applications include consumer appliance controllers, simple sensor interfaces, LED lighting controllers, small white-goods motor controls, and educational/development boards. The PIC16C57-XT/SS is well-suited where an 8-bit MCU with modest memory and GPIO is sufficient and BOM cost must be minimized.
When designing, ensure the oscillator load capacitors match the crystal specification; the absence of an internal oscillator requires an external clock source for the XT variant. Programming is performed via Microchip MPLAB PM3 or compatible device programmers.
This page synthesizes distributor pricing, same-package pin-compatible Microchip drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for PIC16C57-XT/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-XT/SS (same form factor and footprint) — differing in Program Memory Size, Oscillator Type, Package, Timers, Program Memory Type.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C57-XTI/SS
✅ Drop-In✓ In Stock
$3.72 / Unit
View Datasheet →PIC16C57T-RCI/SS
✅ Drop-In✓ In Stock
$1.7 / Unit
View Datasheet →PIC16C57T-RCE/SS
✅ Drop-In✓ In Stock
$4.15 / Unit
View Datasheet →PIC16C55-XT/SS
✅ Drop-In✓ In Stock
$2.42 / Unit
View Datasheet →PIC16C55-XTI/SS
✅ Drop-In✓ In Stock
$2.74 / Unit
View Datasheet →PIC16C56-XTE/SO
✅ Drop-In✓ In Stock
$2.41 / Unit
View Datasheet →PIC16C57-XT/SS Maximum Ratings & Electrical Characteristics
| Core | PIC 8-bit RISC |
| Family | PIC16C5X |
| Program Memory Type | OTP EPROM |
| Program Memory Size | 3 KB (2 K x 12) |
| RAM Size | 72 bytes |
| I/O Pins | 20 |
| Maximum Clock Frequency | 4 MHz |
| Instruction Word Width | 12 bits |
| Data Path Width | 8 bits |
| Supply Voltage | 3.3 V to 5 V |
| Timers | 8-bit TMR0 with programmable prescaler |
| Hardware Stack Depth | 2 levels |
| Addressing Modes | Direct, Indirect, Relative |
| Package | 28-pin SSOP (5.30 mm body) |
| Oscillator Type | XT (external crystal/resonator, 4 MHz) |
| Operating Temperature | 0C to +70C (commercial) |
| Mounting Type | Surface Mount |
PIC16C57-XT/SS Pin Configuration
| Pin 1 | VDD — Positive supply voltage (3.3 V to 5 V) |
| Pin 2 | OSC1 — Crystal/oscillator input (XT mode, 4 MHz) |
| Pin 3 | OSC2 — Crystal/oscillator output (XT mode) |
| Pin 4 | MCLR — Master Clear reset input (active low) |
| Pin 5 | RA0 — GPIO port A bit 0 |
| Pin 6 | RA1 — GPIO port A bit 1 |
| Pin 7 | RA2 — GPIO port A bit 2 |
| Pin 8 | RA3 — GPIO port A bit 3 |
| Pin 9 | RB0 — GPIO port B bit 0 |
| Pin 10 | RB1 — GPIO port B bit 1 |
| Pin 11 | RB2 — GPIO port B bit 2 |
| Pin 12 | RB3 — GPIO port B bit 3 |
| Pin 13 | RB4 — GPIO port B bit 4 |
| Pin 14 | VSS — Ground reference |
| Pin 15 | RB5 — GPIO port B bit 5 |
| Pin 16 | RB6 — GPIO port B bit 6 |
| Pin 17 | RB7 — GPIO port B bit 7 |
| Pin 18 | RC0 — GPIO port C bit 0 |
| Pin 19 | RC1 — GPIO port C bit 1 |
| Pin 20 | RC2 — GPIO port C bit 2 |
| Pin 21 | RC3 — GPIO port C bit 3 |
| Pin 22 | RC4 — GPIO port C bit 4 |
| Pin 23 | RC5 — GPIO port C bit 5 |
| Pin 24 | RC6 — GPIO port C bit 6 |
| Pin 25 | RC7 — GPIO port C bit 7 |
| Pin 26 | T0CKI — Timer0 clock input (shared with RC0) |
| Pin 27 | NC — Not connected (per datasheet) |
| Pin 28 | NC — Not connected (per datasheet) |
Typical Applications
PIC16C57-XT/SS is suitable for 6 applications: Consumer Appliance Control, Simple Sensor Interface Module, LED Lighting Controller, Educational Development Board, Small White-Goods Motor Control, Remote Control and IR Decoder.
Consumer Appliance Control
The PIC16C57-XT/SS is well suited to consumer appliance controllers such as washing machines, microwaves, and small kitchen appliances. Its 3 KB of OTP program memory stores the main control loop and timing state machines, while the 8-bit TMR0 counter handles motor PWM timing, sensor sampling intervals, and user-input debouncing. The 20 GPIO pins drive relays, triac controls, keypads, and seven-segment LED displays directly without external logic. Operating from a single 3.3 V to 5 V supply simplifies the power section, and the low cost per unit makes it ideal for high-volume appliance production. Compared with newer PIC16F1xxx MCUs, the PIC16C57-XT/SS saves approximately 30% on BOM cost for designs that do not require field firmware updates.
Recommended
Simple Sensor Interface Module
For sensor interface modules such as temperature loggers, humidity sensors, and basic alarm panels, the PIC16C57-XT/SS provides a compact, low-power MCU with sufficient GPIO for multiple analog and digital sensor inputs. The 72 bytes of RAM handle small data buffers and averaging algorithms, while the 12-bit instruction width keeps firmware compact enough to fit complex calibration routines in 3 KB. The 4 MHz XT oscillator drives accurate ADC sampling rates through software timing loops. With only 20 I/O available, designs use multiplexing or external I/O expanders for higher-channel-count sensor arrays, but the PIC16C57-XT/SS is cost-optimal for 4- to 8-channel sub-systems found in HVAC and building automation.
Recommended
LED Lighting Controller
In LED lighting controllers for decorative, architectural, and signage applications, the PIC16C57-XT/SS drives multiple LED channels via PWM generated in software using TMR0 interrupts. The 20 GPIO pins can directly sink 20 LED strings with current-limiting resistors, eliminating the need for an external LED driver in low-power installations. Its 3 KB program memory accommodates complex chase patterns, color-mixing sequences, and remote-control decoding for IR or RF receivers. Operating from 3.3 V to 5 V matches standard LED driver ICs, and the SSOP-28 footprint allows compact PCB designs for inline LED controllers. Compared with PIC12F/16F1xxx, the PIC16C57-XT/SS offers more I/O at lower unit cost but trades off flash memory for OTP.
Recommended
Educational Development Board
The PIC16C57-XT/SS is a popular choice for educational development boards and microcontroller training kits because of its simple RISC architecture, 12-bit instruction set, and extensive academic documentation. Students learn core embedded concepts - GPIO manipulation, timer interrupts, polling loops - on a device with just enough complexity to be instructive but not overwhelming. The 28-SSOP package is breadboard-friendly with SSOP-to-DIP adapters, and the 4 MHz XT oscillator supports predictable timing for lab exercises. PIC16C5X assembly programming remains part of many electrical engineering curricula, and the PIC16C57-XT/SS is widely available from hobbyist suppliers and educational distributors at low unit cost.
Recommended
Small White-Goods Motor Control
For small white-goods motor control applications such as fans, blenders, and small pumps, the PIC16C57-XT/SS generates triac-firing-angle control via software-timed interrupts using TMR0. The 20 GPIO pins drive user-interface keypads, indicator LEDs, and zero-cross detection circuits directly. Its 72 bytes of RAM handle the commutation table for 4-pole BLDC motors or stepper sequencing for small universal motors. The 3 KB program memory accommodates speed profiles, soft-start ramps, and overcurrent protection logic. Compared with dedicated motor-control MCUs, the PIC16C57-XT/SS trades off advanced PWM peripherals for cost savings in high-volume sub-100W appliance designs.
Recommended
Remote Control and IR Decoder
In remote control transmitters and IR decoders for consumer electronics, the PIC16C57-XT/SS handles carrier generation, button scanning, and decoding logic with minimal external components. The 8-bit TMR0 generates the 38 kHz carrier for IR transmission, while the same timer captures incoming RC5 or NEC protocol pulses. With 20 GPIO, the device supports up to 16-button keypads via matrix scanning plus 4 status LED indicators. Its 3 KB program memory accommodates multiple protocol stacks and button-mapping tables. The PIC16C57-XT/SS is widely used in TV, set-top-box, and audio-system remotes where BOM cost under 50 cents per unit is essential.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C57-XT/SS — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C57-XTI/SS | PIC16C57T-RCI/SS | PIC16C57T-RCE/SS | PIC16C55-XT/SS | PIC16C55-XTI/SS |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-SSOP | 28-SSOP - same | 28-SSOP - same | 28-SSOP - same | 28-SSOP - same | 28-SSOP - same |
| Program Memory | 3 KB OTP EPROM | 3 KB OTP EPROM | 3 KB OTP EPROM | 3 KB OTP EPROM | 1.5 KB OTP EPROM (-50%) | 1.5 KB OTP EPROM (-50%) |
| RAM | 72 bytes | 72 bytes | 72 bytes | 72 bytes | 24 bytes (-67%) | 24 bytes (-67%) |
| I/O Pins | 20 | 20 | 20 | 20 | 20 | 20 |
| Oscillator Type | XT (4 MHz) | XT (4 MHz) | RC (up to 4 MHz) | RC (up to 4 MHz) | XT (4 MHz) | XT (4 MHz) |
| Operating Temperature | 0C to +70C (commercial) | -40C to +85C (industrial) | -40C to +85C (industrial) | -40C to +85C (industrial, extended) | 0C to +70C (commercial) | -40C to +85C (industrial) |
| Supply Voltage | 3.3 V to 5 V | 3.3 V to 5 V | 3.3 V to 5 V | 3.3 V to 5 V | 3.3 V to 5 V | 3.3 V to 5 V |
Key Differentiators
- Largest program memory in PIC16C5X 28-SSOP family (vs PIC16C55-XT/SS)
- Standard commercial temperature range minimizes BOM cost (vs PIC16C57-XTI/SS)
- XT oscillator variant provides best frequency stability (vs PIC16C57T-RCI/SS)
Design Notes
Decouple the VDD pin (pin 1) with a 100 nF ceramic capacitor placed within 5 mm of the package, plus a 10 uF bulk tantalum or electrolytic capacitor on the board. The PIC16C57-XT/SS draws typical operating current under 5 mA at 4 MHz, but transient current during EPROM programming can spike to 30 mA per Microchip datasheet 30403D. For battery-powered designs, use the PIC16C57C-04/SS low-power CMOS variant to reduce supply current by approximately 50%.
The 28-SSOP package has a 0.65 mm pitch and 5.30 mm body width, requiring fine-pitch PCB layout. Per IPC-7351 land pattern guidelines, use NSMD (non-solder-mask-defined) pads with 0.4 mm width and 0.4 mm length to reduce solder joint stress. Place the crystal load capacitors (typically 22 pF for 4 MHz XT) within 3 mm of OSC1 and OSC2, and keep the oscillator traces short and shielded from noisy signal lines to avoid coupling that disrupts timing.
Three pitfalls to avoid with the PIC16C57-XT/SS: (1) The OTP EPROM cannot be erased after programming - use the windowed JW package for development and prototypes; (2) The 2-level hardware stack cannot be reconfigured - deep subroutine nesting will corrupt the return address; (3) The MCLR pin must be pulled high through a 10 kohm resistor and cannot be left floating, or the device may intermittently reset. Per Microchip datasheet 30403D section on reset circuitry, use an RC network on MCLR for brown-out protection.
The PIC16C57-XT/SS lacks Schmitt-trigger inputs on most GPIO, so noisy input signals can cause metastability in interrupt-driven firmware. Per Microchip datasheet 30403D, the T0CKI pin (shared with RC0) has Schmitt-trigger input; for other inputs, add an external Schmitt-trigger buffer (74HC14) or implement software debouncing with a 1 ms polling delay. Keep digital switching traces away from analog sensor inputs to avoid conducted EMI coupling into ADC-free analog comparator circuits.
Compliance Information
PIC16C57-XT/SS is in the legacy PIC16C5X family predating RoHS; pin/lead finish may not be RoHS compliant. Per Microchip NRND (Not Recommended for New Designs) notice, new designs should consider PIC16F1xxx flash equivalents. AEC-Q100 not applicable - this is a commercial-temperature MCU.
