PIC16C56A-04E/SS - 1KB OTP 8-bit MCU, 4MHz, SSOP-20 | Microchip
MPN: PIC16C56A-04E/SS β End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.28 | $2.28 |
| 10 | $2.05 | $20.50 |
| 100 | $1.82 | $182.00 |
| 500 | $1.55 | $775.00 |
| 1,000 | $1.32 | $1,320.00 |
PIC16C56A-04E/SS Overview
An OTP EPROM-based microcontroller is a one-time-programmable 8-bit MCU whose program memory is implemented in EPROM cells; once blown, the code cannot be electrically erased, which is why OTP parts are designed for low-to-medium volume production where mask-ROM NRE costs are not justified. Within the broader silicon taxonomy, OTP MCUs sit under the family of EPROM/ROM-based microcontrollers, which themselves fall under 8-bit microcontrollers, then microcontrollers (MCU), and finally the integrated circuits (IC) category. The PIC16C5X family is Microchip's baseline low-cost, high-performance RISC architecture family, delivering 33 single-word, single-cycle instructions (branches take two cycles) and 2:1 code compression versus other 8-bit MCUs in its class.
The 04 speed grade denotes a 4MHz oscillator maximum, and the E suffix designates the extended -40C to +125C operating temperature range suitable for industrial and automotive under-hood applications. The SS package indicates a 20-pin Shrink Small Outline (SSOP, 0.209 inch / 5.30mm body width) gull-wing surface-mount outline. With twelve I/O lines and the low pin count, this device targets cost-sensitive embedded control such as appliance controllers, sensor interfaces, LED drivers, and automotive body controllers where extended-temperature reliability is required.
Architecturally, the PIC16C56A uses a Harvard-style separated program/data bus with a 12-bit program word and an 8-bit data path. The OTP memory of 1024 12-bit words gives roughly 1.5KB of code space, and the integrated peripherals - POR, WDT, and one 8-bit timer - are sufficient for simple state-machine and timing control loops. Because the part is OTP rather than Flash, it cannot be reprogrammed in-circuit; production programming requires a device programmer such as the MPLAB PM3 universal device programmer.
Typical applications include automotive body and chassis sub-assemblies (such as mirror controllers, seat switches, and simple sensor conditioning nodes), industrial appliance control (washing-machine sub-controllers, HVAC damper drivers), and cost-sensitive consumer electronics (remote controls, LED signage controllers, and small toys). The wide 3V to 5.5V range also allows direct operation from a regulated 5V rail or two alkaline cells.
When designing with this part, remember that OTP is one-time programmable - firmware bugs cannot be fixed after programming without re-rolling a new silicon lot, so pre-production verification on the pin-compatible PIC16F56 Flash version is recommended. Decoupling must include a 100nF ceramic capacitor between VDD and VSS placed within 5mm of the package, and unused I/O pins should be configured as outputs to minimize current consumption.
This page synthesizes distributor pricing, pin-compatible drop-in alternatives, and practical design notes not found in the manufacturer datasheet - giving engineers a faster, side-by-side comparison for the PIC16C56A-04E/SS and its closest SSOP-20 substitutes in the PIC16C5X family and competitor portfolios.
Drop-in alternatives for PIC16C56A-04E/SS 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 PIC16C56A-04E/SS (same form factor and footprint) β differing in Program Memory Size, Program Memory Type, Package, RoHS Status, Timers.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
PIC16C56A-04/SS
β Drop-Inπ Reference alternative (not in catalog)
PIC16C56A-04E/SO
β Drop-Inπ Reference alternative (not in catalog)
PIC16C56A-04E/P
β Drop-Inβ In Stock
$1.21 / Unit
View Datasheet βPIC16C55A-04E/SS
β Drop-Inβ In Stock
$2.05 / Unit
View Datasheet βPIC16C57C-04E/SS
β Drop-Inβ In Stock
$2.85 / Unit
View Datasheet βPIC16F56-I/SS
β Drop-Inπ Reference alternative (not in catalog)
PIC16C56A-04E/SS Maximum Ratings & Electrical Characteristics
| Program Memory Type | OTP EPROM |
| Program Memory Size | 1K x 12 words (1.5 KB) |
| CPU Core | PIC 8-bit RISC |
| Instruction Set | 33 single-word instructions (12-bit wide) |
| Maximum Clock Frequency | 4 MHz (04 speed grade) |
| Supply Voltage Range | 3 V to 5.5 V |
| I/O Pins | 12 |
| Timers | 1 x 8-bit Timer/Counter |
| Watchdog Timer (WDT) | Yes (on-chip) |
| Power-On Reset (POR) | Yes (on-chip) |
| Operating Temperature Range | -40 C to +125 C (E = extended) |
| Package | 20-pin SSOP (5.30 mm body width) |
| Mounting Type | Surface Mount (gull-wing) |
| Process Technology | CMOS |
| Programming Method | External device programmer (e.g., MPLAB PM3) |
| RoHS Status | non-compliant (windowed/extended-temp OTP, legacy part) |
PIC16C56A-04E/SS Pin Configuration
| Pin 1 | RA0 β Bidirectional I/O port A bit 0 |
| Pin 2 | RA1 β Bidirectional I/O port A bit 1 |
| Pin 3 | RA2 β Bidirectional I/O port A bit 2 |
| Pin 4 | RA3 β Bidirectional I/O port A bit 3 |
| Pin 5 | RA4 β Bidirectional I/O port A bit 4 (open-drain option) |
| Pin 6 | RB0 β Bidirectional I/O port B bit 0 |
| Pin 7 | RB1 β Bidirectional I/O port B bit 1 |
| Pin 8 | VSS β Ground reference |
| Pin 9 | OSC1 β Oscillator input / external clock input |
| Pin 10 | OSC2 β Oscillator output (crystal mode) |
| Pin 11 | RB2 β Bidirectional I/O port B bit 2 |
| Pin 12 | RB3 β Bidirectional I/O port B bit 3 |
| Pin 13 | RB4 β Bidirectional I/O port B bit 4 |
| Pin 14 | RB5 β Bidirectional I/O port B bit 5 |
| Pin 15 | RB6 β Bidirectional I/O port B bit 6 |
| Pin 16 | RB7 β Bidirectional I/O port B bit 7 |
| Pin 17 | RC0 β Bidirectional I/O port C bit 0 |
| Pin 18 | RC1 β Bidirectional I/O port C bit 1 |
| Pin 19 | VDD β Positive supply voltage (3.0V to 5.5V) |
| Pin 20 | /MCLR β Master Clear reset input, active low |
Typical Applications
PIC16C56A-04E/SS is suitable for 6 applications: Automotive Body Controllers, Industrial Appliance Control, Consumer Electronics (Remote Controls, Toys), Sensor Interface Modules, LED Lighting Controllers, Battery-Powered Embedded Devices.
Automotive Body Controllers
The PIC16C56A-04E/SS fits automotive body and chassis sub-assemblies including mirror adjusters, seat-position switches, window-lift sub-controllers, and simple sensor-conditioning nodes. Its -40C to +125C extended temperature grade (denoted by the E suffix) handles under-hood and cabin thermal stress, and the 12 I/O lines are sufficient to drive relays, sense switches, and PWM LED backlights. The 4 MHz core and 12-bit-wide OTP program memory deliver deterministic 1us instruction cycles for real-time control loops, while the on-chip Watchdog Timer guards against code-lockup in noisy automotive electrical environments. Compared to a Flash MCU, the OTP-only program memory prevents firmware tampering - a security plus for OEM production. Power dissipation is minimal at 3V/5V, typically under 100 mW, so no heatsink is required.
Recommended
Industrial Appliance Control
In washing machines, HVAC damper drivers, and small industrial controllers, the PIC16C56A-04E/SS is well matched because its 3V to 5.5V supply range accepts common regulated 5V rails, and its 12 I/O lines can scan keypads, drive triacs via optocouplers, and read NTC temperature sensors. The single 8-bit Timer/Counter generates the time-base for triac firing and motor-speed PWM, while the Watchdog Timer recovers from mains-induced brownouts. The SSOP-20 surface-mount package supports high-density control boards where through-hole PDIP would not fit. For volume production, OTP silicon costs less per unit than Flash, which is critical when appliance manufacturers ship millions of units per year.
Recommended
Consumer Electronics (Remote Controls, Toys)
Cost-sensitive consumer products such as IR remote controls, simple toys, LED signage controllers, and electronic game peripherals benefit from the PIC16C56A-04E/SS's sub-$1 price at high volume and small SSOP-20 footprint. The 4 MHz core is more than fast enough for RC5/SIRC IR protocol encoding/decoding, and the 12 I/O can scan key matrices up to 4x4. The Watchdog Timer protects against low-battery brown-outs common in battery-powered remote controls, while the 3V operation directly supports two alkaline cells. The OTP memory gives OEMs confidence that competitors cannot easily read out the firmware via the standard Flash-readback technique.
Recommended
Sensor Interface Modules
The PIC16C56A-04E/SS is well suited as a low-cost sensor-interface front-end for thermistor signal conditioning, hall-effect switches, and optical interrupters. The 8-bit ADC-less architecture relies on ratiometric sensing through the I/O pins with on-chip comparators on some PIC16C5X family members, or simple RC charge-time measurement using the built-in Timer/Counter. The 12 I/O lines easily accommodate multiple sensor inputs and digital outputs, while the 4 MHz clock provides enough resolution for ms-scale timing measurements. Industrial-grade extended temperature ensures sensor modules operate reliably in outdoor enclosures.
Recommended
LED Lighting Controllers
For low-cost LED drivers in decorative lighting, signage, and architectural fixtures, the PIC16C56A-04E/SS provides the PWM and pattern-control logic at a BOM cost under $1. The 12 I/O can drive multiple MOSFETs through external drivers for RGB channels or seven-segment displays, and the Timer/Counter generates PWM frequencies above the audible band to avoid flicker. The wide 3V to 5.5V supply range supports direct operation from a single Li-ion cell or a 5V regulated rail. The OTP memory prevents end users from cloning custom lighting patterns.
Recommended
Battery-Powered Embedded Devices
The PIC16C56A-04E/SS suits battery-powered devices such as wireless sensor nodes, electronic shelf labels, and simple IoT edge devices because its CMOS process delivers nanoampere-level sleep currents and its 3V operation directly supports two alkaline or NiMH cells. The Watchdog Timer wakes the MCU periodically to transmit sensor data, and the 8-bit Timer/Counter can be used for low-power timing. The OTP memory reduces active-mode current draw compared to Flash, extending battery life. The extended -40C to +125C temperature range ensures outdoor and industrial deployments.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C56A-04E/SS β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C56A-04/SS | PIC16C55A-04E/SS | PIC16C57C-04E/SS | PIC16F56-I/SS |
|---|---|---|---|---|---|
| Package | SSOP-20 (5.30 mm) | SSOP-20 (same) | SSOP-20 (same) | SSOP-20 (same) | SSOP-20 (same) |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Program Memory | 1K x 12 OTP (1.5 KB) | 1K x 12 OTP (same) | 512 x 12 OTP (smaller) | 2K x 12 OTP (larger) | 1K x 12 Flash (reprogrammable) |
| Max Clock Frequency | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 20 MHz (max) |
| Supply Voltage | 3.0 V to 5.5 V | 3.0 V to 5.5 V | 3.0 V to 5.5 V | 3.0 V to 5.5 V | 2.0 V to 5.5 V (wider) |
| Operating Temperature | -40 C to +125 C (extended) | -40 C to +85 C (industrial) | -40 C to +125 C (extended) | -40 C to +125 C (extended) | -40 C to +85 C (industrial) |
| I/O Pins | 12 | 12 | 12 | 20 (full port) | 12 |
| Memory Type | OTP EPROM | OTP EPROM | OTP EPROM | OTP EPROM | Flash (reprogrammable) |
| Lifecycle Status | Obsolete | Obsolete | Obsolete | Obsolete | Active |
Key Differentiators
- Extended -40C to +125C operating temperature range (vs PIC16C56A-04/SS)
- Active vs obsolete product lifecycle (vs PIC16F56-I/SS)
- Larger 1.5 KB program memory vs 768-byte siblings (vs PIC16C55A-04E/SS)
Design Notes
OTP EPROM on PIC16C56A-04E/SS is one-time-programmable - firmware bugs cannot be fixed by re-programming in the field. Estimated: a single mask-spin at a 100K-unit order may take 8-12 weeks and cost several thousand dollars NRE. Always prototype on the pin-compatible PIC16F56-I/SS (Flash) and validate firmware before committing to OTP silicon. Use a windowed PIC16C56A-04E/JW sample only for engineering verification, never in production.
Place a 100 nF decoupling capacitor between VDD (pin 19) and VSS (pin 8) within 5 mm of the package, and add a 10 uF bulk capacitor at the regulator output. Keep the OSC1/OSC2 traces short and surround them with a ground pour to reduce EMI; crystal load capacitors should be sized per Microchip's AN588 application note. Leave /MCLR (pin 20) tied to VDD through a 10 kohm pull-up if not used for external reset.
PIC16C56A-04E/SS typical active current is below 2 mA at 4 MHz / 5 V, giving power dissipation under 10 mW and junction temperature rise negligible above ambient. The SSOP-20 thermal resistance is approximately 100 C/W, but this never becomes a limiting factor at MCU-level currents. No heatsink is required under any normal operating profile.
Compliance Information
PIC16C56A-04E/SS is a pre-RoHS-2 Microchip part and is marked non-compliant for RoHS due to SnPb termination on legacy OTP silicon. Microchip does not advertise AEC-Q100 qualification for this family; automotive customers should verify with the manufacturer.