PIC16C57-HS/P - 8-bit OTP MCU 20MHz 3KB | Microchip
MPN: PIC16C57-HS/P β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $7.76 | $7.76 |
| 10 | $6.98 | $69.80 |
| 100 | $5.83 | $583.00 |
| 500 | $5.1 | $2,550.00 |
| 1,000 | $4.62 | $4,620.00 |
PIC16C57-HS/P Overview
An OTP microcontroller is a variant of programmable microcontroller in which the program memory can be written once via a device programmer and is then non-volatile and non-erasable. The PIC16C57 belongs to the baseline PIC16 family hierarchy, which sits under the broader PICmicro 8-bit microcontroller taxonomy and ultimately under Microchip's PIC microcontroller portfolio. OTP parts sit alongside EPROM windowed, Flash, and ROM-based variants in the same silicon family, with OTP favored for cost-sensitive, high-volume production where field re-programmability is not required.
Key features of the PIC16C57-HS/P include a 12-bit wide instruction word with 33 single-word/single-cycle instructions, a two-level deep hardware stack, eight-level deep hardware call stack, direct/indirect/relative addressing modes, a single 8-bit real-time clock/counter (TMR0) with 8-bit programmable prescaler, 20 digital I/O pins capable of sourcing/sinking up to 25mA per pin, watchdog timer with on-chip RC oscillator, power-on reset, power-saving SLEEP mode, and code-protect security fuse. Operating voltage is 3.0V to 5.5V with commercial and industrial temperature grades available.
The architecture uses a Harvard-style RISC design with separate program and data buses, two 8-bit file-select registers (FSR) for indirect addressing, and seven or eight special function hardware registers mapped into a common I/O space. Throughput is approximately 5 million instructions per second at 20MHz, giving cycle times of 200ns - roughly 2:1 code compression over comparable 8-bit CISC microcontrollers in its class.
Typical applications include consumer appliance controls, simple sensor interfaces, automotive body electronics (non-safety), battery chargers, low-end motor control loops, security keypads, and replacement of discrete logic in glue-logic consolidation designs. The 28-pin PDIP package remains popular for through-hole prototyping, educational platforms, and legacy industrial equipment where socketed replacement is required.
When designing with this part, ensure the OTP programming step is integrated into the manufacturing flow because field firmware updates are impossible after programming. For designs requiring in-system reprogrammability, consider migrating to the pin-compatible PIC16F57 flash variant.
This page synthesizes distributor pricing, drop-in alternatives within the same 28-pin PDIP footprint, and practical design notes not collected in any single manufacturer datasheet.
Drop-in alternatives for PIC16C57-HS/P β 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-HS/P (same form factor and footprint) β differing in Package, Timers, Core Architecture, Watchdog Timer, Program Memory Size.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
PIC16C57-LP/P
β Drop-Inβ In Stock
$1.74 / Unit
View Datasheet βPIC16C57-RC/P
β Drop-Inπ Reference alternative (not in catalog)
PIC16C57-XT/P
β Drop-Inπ Reference alternative (not in catalog)
PIC16F57-I/P
β Drop-Inπ Reference alternative (not in catalog)
PIC16C57C-20I/P
β Drop-Inπ Reference alternative (not in catalog)
PIC16C57-10I/P
β Drop-Inβ In Stock
$1.75 / Unit
View Datasheet βPIC16C57-HS/P Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC16 8-bit RISC (Harvard) |
| Program Memory Type | OTP (One-Time Programmable) EPROM |
| Program Memory Size | 2K x 12 (3 KB words) |
| Data RAM | 72 bytes |
| Maximum CPU Frequency | 20 MHz |
| Instruction Word Width | 12 bits |
| Number of Instructions | 33 (single-word, single-cycle) |
| Operating Voltage | 3.0 V to 5.5 V |
| Digital I/O Pins | 20 |
| I/O Pin Current (sink/source) | 25 mA per pin |
| Timers | TMR0 8-bit with 8-bit prescaler |
| Stack Depth | 2 levels (hardware) |
| Watchdog Timer | Yes, with on-chip RC oscillator |
| Package | 28-pin PDIP (0.600 inch, 15.24mm) |
| Operating Temperature | 0C to +70C (commercial) |
| Oscillator Mode | HS (High-Speed crystal/ceramic resonator, up to 20 MHz) |
PIC16C57-HS/P Pin Configuration
| Pin 1 | RA2 β Port A bit 2 (bidirectional I/O) |
| Pin 2 | RA3 β Port A bit 3 (bidirectional I/O) |
| Pin 3 | T0CKI β TMR0 clock input / RA4 |
| Pin 4 | MCLR β Master Clear (reset, active low) |
| Pin 5 | VSS β Ground reference |
| Pin 6 | RB0 β Port B bit 0 (bidirectional I/O) |
| Pin 7 | RB1 β Port B bit 1 (bidirectional I/O) |
| Pin 8 | RB2 β Port B bit 2 (bidirectional I/O) |
| Pin 9 | RB3 β Port B bit 3 (bidirectional I/O) |
| Pin 10 | RB4 β Port B bit 4 (bidirectional I/O) |
| Pin 11 | RB5 β Port B bit 5 (bidirectional I/O) |
| Pin 12 | RB6 β Port B bit 6 (bidirectional I/O) |
| Pin 13 | RB7 β Port B bit 7 (bidirectional I/O) |
| Pin 14 | VDD β Positive supply (3.0V to 5.5V) |
| Pin 15 | OSC2 β Oscillator output (crystal/resonator connection) |
| Pin 16 | OSC1 β Oscillator input (crystal/resonator connection) |
| Pin 17 | RC0 β Port C bit 0 (bidirectional I/O) |
| Pin 18 | RC1 β Port C bit 1 (bidirectional I/O) |
| Pin 19 | RC2 β Port C bit 2 (bidirectional I/O) |
| Pin 20 | RC3 β Port C bit 3 (bidirectional I/O) |
| Pin 21 | RC4 β Port C bit 4 (bidirectional I/O) |
| Pin 22 | RC5 β Port C bit 5 (bidirectional I/O) |
| Pin 23 | RC6 β Port C bit 6 (bidirectional I/O) |
| Pin 24 | RC7 β Port C bit 7 (bidirectional I/O) |
| Pin 25 | RD0 β Port D bit 0 (bidirectional I/O) |
| Pin 26 | RD1 β Port D bit 1 (bidirectional I/O) |
| Pin 27 | RD2 β Port D bit 2 (bidirectional I/O) |
| Pin 28 | RD3 β Port D bit 3 (bidirectional I/O) |
Typical Applications
PIC16C57-HS/P is suitable for 7 applications: Consumer Appliance Control, Battery Charger Control, Security Keypad / Access Control, Educational / Hobbyist Platforms, Low-End Motor Speed Control, Legacy Industrial Equipment Drop-In, Sensor Interface Bridge.
Consumer Appliance Control
The PIC16C57-HS/P is well suited for consumer appliance controllers such as washing machines, microwave ovens, and small kitchen devices where 20 MHz CPU performance is needed to drive user-interface scanning and simple timing loops. The 20 digital I/O lines are sufficient for keypad matrix input, 7-segment or LCD segment output, and relay drivers. Compared with discrete logic designs, the PIC16C57-HS/P reduces PCB area by 4-6x while adding reconfigurable behavior via software. Pair with a ULN2003A relay driver for 200V load switching.
Recommended
Battery Charger Control
Battery charger control loops benefit from the PIC16C57-HS/P's 20 MHz CPU and 8-bit TMR0 with 8-bit programmable prescaler for accurate charge timing. The HS oscillator supports a precise 32.768 kHz-derived or 20 MHz time base, enabling Coulomb-counting approximations or simple V/I charge profiling. The OTP memory locks the charge algorithm at production time, protecting against tampering. Use with an external op-amp like MCP6001 for current sense amplification and a MOSFET for PWM pass-element control.
Recommended
Security Keypad / Access Control
The PIC16C57-HS/P handles 4x4 or 5x5 matrix keypads using 8 of its 20 I/O lines for scanning, with the remaining I/O available for relay drivers, LEDs, and a buzzer. The 200ns instruction cycle at 20 MHz ensures no perceptible scan latency, while the on-chip watchdog timer detects lock-up conditions for fail-safe operation. OTP programming locks the access code and prevents firmware cloning. Pair with a 4N35 optocoupler if isolation between keypad and door strike is required.
Recommended
Educational / Hobbyist Platforms
The PIC16C57-HS/P in 28-pin PDIP is a popular teaching platform because it can be programmed with low-cost PIC programmers like the PICkit 2/3 and slotted into a 28-pin DIP socket for fast iteration. The 33-instruction baseline PIC16C5X core introduces students to RISC concepts, Harvard architecture, and accumulator-less register-based programming. Commercial teaching kits and university microcontroller courses use this exact part for lab assignments because of its simplicity and PDIP availability.
Recommended
Low-End Motor Speed Control
Open-loop or simple closed-loop motor speed control uses the PIC16C57-HS/P to generate a PWM drive signal via software bit-banging on TMR0, with duty cycle controlled by a potentiometer on an ADC-less input using RC charge timing. The HS oscillator at 20 MHz gives PWM frequencies well above 20 kHz, above the audible range, eliminating motor whine. Pair with a TC4420 MOSFET driver and an N-channel logic-level MOSFET for H-bridge or half-bridge control of brushed DC motors up to 5A.
Recommended
Legacy Industrial Equipment Drop-In
Industrial equipment built in the 1990s and early 2000s often uses the PIC16C57-HS/P in 28-pin PDIP sockets for control logic. Sourcing the original OTP part is critical for sustaining production of long-lifecycle machines where re-validation of an MCU swap would cost more than the part itself. The 28-pin PDIP socket allows field replacement without desoldering, and the OTP memory prevents unauthorized firmware modifications - a regulatory plus in some industrial certifications.
Recommended
Sensor Interface Bridge
The PIC16C57-HS/P acts as a sensor-to-protocol bridge for legacy sensors that output simple pulse trains or analog thresholds. Its 20 MHz CPU supports software UART bit-banging up to 9600 baud, and the TMR0 captures edge timing of pulse-output flowmeters or proximity sensors. The OTP memory locks the sensor calibration coefficients at production. For designs where the sensor characteristics are stable, OTP lock-in is preferred over Flash for security and reliability reasons.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C57-HS/P β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C57-LP/P | PIC16C57-RC/P | PIC16C57-XT/P | PIC16F57-I/P | PIC16C57-10I/P |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-pin PDIP | 28-pin PDIP - same | 28-pin PDIP - same | 28-pin PDIP - same | 28-pin PDIP - same | 28-pin PDIP - same |
| Program Memory Type | OTP (3KB) | OTP (3KB) - same | OTP (3KB) - same | OTP (3KB) - same | Flash (3KB) - reprogrammable | OTP (3KB) - same |
| Maximum CPU Frequency | 20 MHz | 200 kHz | 4 MHz | 4 MHz | 20 MHz | 10 MHz |
| Oscillator Mode | HS (high-speed crystal) | LP (low-power crystal) | RC (resistor/capacitor) | XT (standard crystal) | HS (high-speed crystal) | HS (high-speed crystal, 10 MHz max) |
| Data RAM | 72 bytes | 72 bytes - same | 72 bytes - same | 72 bytes - same | 72 bytes - same | 72 bytes - same |
| I/O Pins | 20 | 20 - same | 20 - same | 20 - same | 20 - same | 20 - same |
| Operating Voltage | 3.0V to 5.5V | 2.5V to 6.25V | 3.0V to 6.25V | 3.0V to 6.25V | 2.0V to 5.5V | 3.0V to 6.25V |
| In-System Reprogrammable | No (OTP) | No (OTP) | No (OTP) | No (OTP) | Yes (Flash) - key upgrade | No (OTP) |
Key Differentiators
- 20 MHz HS oscillator variant for maximum throughput in 28-pin PDIP (vs PIC16C57-LP/P)
- Pin-compatible Flash upgrade path (vs PIC16F57-I/P)
- Industrial temperature grade available with same die (vs PIC16C57C-20I/P)
Design Notes
The PIC16C57-HS/P draws approximately 2-5 mA active at 5V/20 MHz and 5-20 uA in SLEEP mode, so a 100 nF decoupling capacitor close to VDD (pin 14) is mandatory, plus a 10 uF bulk capacitor on the supply rail. When using a switching regulator upstream, add a ferrite bead and additional LC filtering to keep digital switching noise out of the analog supply if any ADC inputs are routed (note: PIC16C57 has no ADC, but PIC16F57 upgrade candidates may).
Place the crystal or resonator (typically a 20 MHz HC-49S part with 22 pF load capacitors) within 0.5 inch (12 mm) of pins 15 (OSC2) and 16 (OSC1). Keep oscillator traces short, surround them with a ground guard ring, and never route signal traces beneath the crystal can. For the HS mode at 20 MHz, ground plane integrity under the oscillator region is critical to avoid EMI and frequency drift.
Remember that OTP means one-time programmable: any code bug discovered after programming requires physical replacement of the chip. Always prototype with the PIC16F57-I/P first, validate firmware thoroughly, then qualify the PIC16C57-HS/P for production. Also note the two-level hardware stack means deeply nested CALL chains will silently overflow - keep call depth to one level where possible, or restructure code to avoid deep recursion.
For 28-pin PDIP through-hole designs, use a machined-pin IC socket (e.g., 3M 28-pin DIP socket) in production to allow field replacement - critical for legacy industrial equipment with multi-decade service lifecycles. Reserve a clearly labeled silkscreen outline for pin 1 (notch on top, dot at bottom-left). Add a 10 kohm pull-up on MCLR (pin 4) to VDD and a 100 nF cap on MCLR to ground if external reset circuit is used.
Compliance Information
RoHS compliant per Microchip product declaration; lead-free matte-tin finish on PDIP leads. Halogen-free status not explicitly listed in datasheet - set to unknown. Not AEC-Q100 qualified - automotive applications should select PIC16C57C-20I/P industrial grade instead.
