PIC16C57CT-04I/SO - 4MHz 8-Bit OTP MCU, 3KB, 20 I/O | Microchip
MPN: PIC16C57CT-04I/SO β End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.42 | $1.42 |
| 10 | $1.28 | $12.80 |
| 100 | $1.15 | $115.00 |
| 500 | $1.05 | $525.00 |
| 1,000 | $0.95 | $950.00 |
PIC16C57CT-04I/SO Overview
A PIC16C5X microcontroller is an 8-bit fully-static CMOS RISC architecture device designed for low-cost, high-performance embedded control. Within the broader semiconductor taxonomy it sits as: 8-bit microcontroller -> microcontroller -> embedded processor -> semiconductor IC. The PIC16C5X core is Harvard-architecture with 12-bit-wide instructions, providing 2:1 code compression over comparable 8-bit CISC controllers in the same price class. With only 33 single-word instructions, programming complexity is minimal and code density is high, which lowers BOM cost in volume production.
Key features of the PIC16C57CT-04I/SO include a 4 MHz maximum clock, 100 ns instruction execution, 3 KB (2K x 12) OTP program memory, 72 bytes of general-purpose RAM, a reset input, watchdog timer, and 20 bidirectional I/O pins. The 28-pin SOIC (SO) industrial package provides a surface-mount footprint compatible with hand-soldering and standard reflow profiles. Power consumption is low for an OTP CMOS MCU of its era, with the static core supporting fully static operation that allows the clock to be stopped without losing register state.
Architecturally the PIC16C57CT uses a two-stage pipeline and a 12-bit program memory bus with an 8-bit data bus. Unlike later PIC16 mid-range parts, the PIC16C5X family does not feature interrupts, which simplifies real-time control loops because timing is fully deterministic from instruction counting. The OTP memory allows factory programming or one-time field programming via a device programmer, which is commonly used for low-volume production runs or end-of-line customization where mask-ROM volumes are uneconomical.
Typical applications include appliance control, sensor signal conditioning, low-end consumer electronics, industrial timers and counters, automotive body controllers (legacy systems), simple LED driving, and remote-control transmitters. The 20 I/O pins and 33-instruction set enable direct interfacing to keypads, seven-segment displays, and discrete analog signals via simple RC networks. The wide industrial temperature range also supports outdoor or factory-floor deployments.
When designing with the PIC16C57CT-04I/SO, plan the program memory as OTP - code must be 100% verified before programming because there is no in-circuit reprogramming. Use a Watchdog Timer to recover from brown-out events, add a decoupling capacitor of 0.1 uF close to VDD, and reserve an RC network on MCLR for clean reset behavior. The -04 speed grade means the oscillator must be selected to keep instruction execution within the 100 ns cycle budget at the chosen VDD.
This page synthesizes distributor pricing, drop-in OTP and windowed EPROM alternatives in the same 28-SOIC footprint, and design notes not found in the manufacturer datasheet.
Drop-in alternatives for PIC16C57CT-04I/SO 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 PIC16C57CT-04I/SO (same form factor and footprint) β differing in Core Architecture, Instruction Cycle Time, Package, RoHS Status, Program Memory Type.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
PIC16C57C-04I/SO
β Drop-Inπ Reference alternative (not in catalog)
PIC16C57CT-04/SO
β Drop-Inπ Reference alternative (not in catalog)
PIC16C57CT-04E/SO
β Drop-In β οΈ εζ°εΎ ιͺθ―β In Stock
$4.37 / Unit
View Datasheet βPIC16C57C-20/SO
β Drop-Inβ In Stock
$2.89 / Unit
View Datasheet βPIC16F57-I/SO
β Drop-Inπ Reference alternative (not in catalog)
PIC16C57CT-04I/SO Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC 8-bit RISC (Harvard) |
| Family | PIC16C5X |
| Core Size | 8-bit |
| Maximum Clock Frequency | 4 MHz |
| Instruction Cycle Time | 100 ns |
| Program Memory Type | OTP (One-Time Programmable) |
| Program Memory Size | 3 KB (2K x 12) |
| RAM Size | 72 bytes |
| Number of I/O Pins | 20 |
| Number of Instructions | 33 single-word |
| Package | 28-SOIC (SO) |
| Mounting Type | Surface Mount |
| Operating Temperature | -40C to +85C (Industrial) |
| Watchdog Timer | Yes |
| RoHS Status | Non-Compliant (OTP, legacy) |
| Data Converters | None |
PIC16C57CT-04I/SO Pin Configuration
| Pin 1 | RA2 β I/O port A bit 2 |
| Pin 2 | RA3 β I/O port A bit 3 |
| Pin 3 | T0CKI β Timer0 clock input / I/O |
| Pin 4 | MCLR β Master clear reset input |
| Pin 5 | VSS β Ground reference |
| Pin 6 | RB0 β I/O port B bit 0 |
| Pin 7 | RB1 β I/O port B bit 1 |
| Pin 8 | RB2 β I/O port B bit 2 |
| Pin 9 | RB3 β I/O port B bit 3 |
| Pin 10 | RB4 β I/O port B bit 4 |
| Pin 11 | RB5 β I/O port B bit 5 |
| Pin 12 | RB6 β I/O port B bit 6 |
| Pin 13 | RB7 β I/O port B bit 7 |
| Pin 14 | VSS β Ground reference |
| Pin 15 | OSC1 β Oscillator input |
| Pin 16 | OSC2 β Oscillator output |
| Pin 17 | RC0 β I/O port C bit 0 |
| Pin 18 | RC1 β I/O port C bit 1 |
| Pin 19 | RC2 β I/O port C bit 2 |
| Pin 20 | RC3 β I/O port C bit 3 |
| Pin 21 | RC4 β I/O port C bit 4 |
| Pin 22 | RC5 β I/O port C bit 5 |
| Pin 23 | RC6 β I/O port C bit 6 |
| Pin 24 | RC7 β I/O port C bit 7 |
| Pin 25 | VSS β Ground reference |
| Pin 26 | VDD β Positive supply voltage |
| Pin 27 | RA0 β I/O port A bit 0 |
| Pin 28 | RA1 β I/O port A bit 1 |
Typical Applications
PIC16C57CT-04I/SO is suitable for 6 applications: Appliance Control Boards, Industrial Timers and Counters, Remote Control Transmitters, LED Display Drivers, Simple Sensor Signal Conditioning, Automotive Body Controllers (Legacy Systems).
Appliance Control Boards
The PIC16C57CT-04I/SO fits appliance control boards such as washing-machine timers, microwave keypads, and dishwasher cycle controllers. Its 3 KB OTP program memory holds complete state-machine code for wash cycles, drying phases, and fault handling, while 20 I/O pins drive relays, triac optocouplers, and seven-segment displays directly. At 4 MHz, the 100 ns instruction cycle is ample to multiplex displays and scan keypads without visible flicker, and the industrial -40C to +85C rating handles kitchen and laundry thermal environments. Unlike flash parts, OTP locks firmware at production, preventing field tampering of safety logic. Recommended companion MPNs: PIC16F57-I/SO (drop-in flash replacement) and ULN2003A (relay driver array).
Recommended
Industrial Timers and Counters
The PIC16C57CT-04I/SO is well suited to industrial timer, counter, and process-interval controllers. Its 33 single-word instructions and fully static CMOS core allow simple software counters and time-base generators without interrupts, which simplifies deterministic timing analysis. The 72-byte RAM supports multiple simultaneous counter variables, while the watchdog timer guards against brown-out-induced code hangups common on factory 24V rails. With 20 I/O pins, the MCU interfaces directly to BCD thumbwheel switches, LED status indicators, and SSR trigger inputs. The -40C to +85C industrial range handles cabinet-mounted deployments. Recommended companion MPNs: PIC16C57C-04I/SO (tube variant) and PC847 optocoupler for 24V signal isolation.
Recommended
Remote Control Transmitters
The PIC16C57CT-04I/SO serves low-cost IR/RF remote control transmitters where its 3 KB OTP memory stores button-scan tables and Manchester-encoded transmission patterns for garage-door openers, ceiling fans, and toy controllers. The 20 I/O pins accept 4x5 matrix keypads directly, and the 4 MHz instruction cycle generates 38 kHz carrier modulation with deterministic sub-microsecond timing. The static CMOS core allows the MCU to wake from sleep between button presses, extending battery life on coin cells. The industrial temperature rating supports outdoor garage-door transmitters exposed to direct sunlight and winter cold. Recommended companion MPNs: TSOP38238 (38 kHz IR receiver companion) and 4 MHz ceramic resonator.
Recommended
LED Display Drivers
The PIC16C57CT-04I/SO drives multiplexed LED matrix and seven-segment displays in scoreboards, price tags, and message boards. The 20 I/O pins can sink an 8-digit seven-segment display plus 8 discrete LEDs with charlieplexing, while the 4 MHz clock executes refresh routines at well above 100 Hz to avoid visible flicker. The 3 KB OTP program memory holds font tables and animation sequences, and the 33-instruction RISC core keeps the code size compact. The CMOS low-power operation reduces heat in enclosed display cabinets. Recommended companion MPNs: ULN2003A (segment driver) and TPIC6B595 high-current shift register for large-matrix implementations.
Recommended
Simple Sensor Signal Conditioning
The PIC16C57CT-04I/SO conditions low-bandwidth sensor signals in HVAC duct sensors, environmental monitors, and basic instrumentation. While it lacks an ADC, external RC networks convert resistive sensors (thermistors, photoresistors) into timing intervals that the PIC measures by counting instruction cycles at 1 us per count - a deterministic and calibration-free approach. The 20 I/O pins handle multiple sensor inputs and alarm outputs, and the 3 KB program memory supports linearization lookup tables. The industrial temperature range ensures outdoor sensor-housing reliability. Recommended companion MPNs: PIC16F57-I/SO (drop-in flash for code updates) and LM35 analog temp sensor with external ADC.
Recommended
Automotive Body Controllers (Legacy Systems)
The PIC16C57CT-04I/SO has historically been used in automotive body controllers for window lifters, seat controllers, mirror adjusters, and simple lighting modules where its 20 I/O pins drive H-bridges and relay coils while 3 KB of OTP memory stores position-memory logic. The industrial -40C to +85C range covers cabin environments, and the CMOS design tolerates the electrical noise of automotive 12V buses. The static core supports sleep mode for parked-vehicle quiescent current budgets below 1 mA. For under-hood or extreme-cold deployments the PIC16C57CT-04E/SO (extended -40C to +125C) variant should be substituted. Recommended companion MPNs: PIC16C57CT-04E/SO (extended temperature) and VNQ5050K high-side driver.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C57CT-04I/SO β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C57C-04I/SO | PIC16C57CT-04/SO | PIC16C57CT-04E/SO | PIC16C57C-20/SO | PIC16F57-I/SO |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-SOIC (SO) | 28-SOIC (SO) - same | 28-SOIC (SO) - same | 28-SOIC (SO) - same | 28-SOIC (SO) - same | 28-SOIC (SO) - same |
| Program Memory | 3 KB OTP (2K x 12) | 3 KB OTP (2K x 12) | 3 KB OTP (2K x 12) | 3 KB OTP (2K x 12) | 3 KB OTP (2K x 12) | 3 KB Flash (2K x 12) |
| Maximum Clock | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 20 MHz | 20 MHz |
| Operating Temperature | -40C to +85C (Industrial) | -40C to +85C | 0C to +70C | -40C to +125C | 0C to +70C | -40C to +85C |
| Memory Type | OTP | OTP | OTP | OTP | OTP | Flash (reprogrammable) |
| RAM Size | 72 bytes | 72 bytes | 72 bytes | 72 bytes | 72 bytes | 72 bytes |
| Number of I/O Pins | 20 | 20 | 20 | 20 | 20 | 20 |
| Lifecycle Status | Obsolete | Obsolete | Obsolete | Obsolete | Obsolete | Active |
Key Differentiators
- Active production replacement with same pinout (vs PIC16F57-I/SO)
- Extended automotive temperature range (vs PIC16C57CT-04E/SO)
- 5x faster instruction execution (vs PIC16C57C-20/SO)
Design Notes
OTP (one-time-programmable) memory on the PIC16C57CT-04I/SO cannot be erased or reprogrammed - any bit-cell programming error is permanent. Per Microchip PIC16C5X datasheet (DS30430F), the device must be 100% code-verified by simulation and emulator (PIC16C5X ICE) before production programming. Allocate engineering time for programmer calibration (VPP=13V typical) and unused code space pattern (typically 0FFF or 0000) per factory programming guide.
Estimated: at 4 MHz and 5V VDD, the PIC16C57CT-04I/SO draws approximately 2-5 mA active and <1 uA sleep, per Microchip PIC16C5X datasheet (DS30430F) DC characteristics. Add a 0.1 uF decoupling capacitor within 5 mm of the VDD pin (pin 26) and a 10 uF bulk capacitor on the same rail. For battery-powered designs use the sleep mode aggressively - the static CMOS core holds registers with the oscillator stopped.
The 28-SOIC footprint is hand-solderable but the 1.27 mm pin pitch requires a fine-tip iron and quality flux. Keep oscillator traces (OSC1/OSC2, pins 15-16) shorter than 20 mm and route them away from high-current relay or triac traces to avoid injected noise on the clock. Place the MCLR pull-up (typically 10 kohm) close to pin 4 with a 100 nF cap to ground for clean power-on-reset behavior.
Compliance Information
Legacy OTP PIC16C5X part predates RoHS transition. Reach status and halogen status not stated in datasheet. Not AEC-Q100 qualified - choose PIC16C57CT-04E/SO for automotive extended-temperature applications. The PIC16F57-I/SO is the recommended RoHS-compliant replacement.
