PIC16C56AT-20/SO - 8-bit OTP MCU 1.5KB ROM 20MHz SOIC-18
MPN: PIC16C56AT-20/SO ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.85 | $2.85 |
| 10 | $2.55 | $25.50 |
| 100 | $2.18 | $218.00 |
| 500 | $1.92 | $960.00 |
| 1,000 | $1.71 | $1,710.00 |
PIC16C56AT-20/SO Overview
Background Knowledge: An 8-bit OTP microcontroller is a single-chip computer built around an 8-bit data path and one-time-programmable (OTP) EPROM or ROM program memory. The PIC16C5X family uses a 12-bit wide instruction word with a Harvard architecture, separating program and data memory for deterministic single-cycle instruction execution. As a member of the broader microcontroller class (microcontroller -> MCU -> embedded controller -> semiconductor), the PIC16C56A belongs to the RISC subset, executes one instruction per instruction cycle (four clock periods), and is offered in masked-ROM (PIC16C56), UV-erasable windowed (PIC16C56 JW), and one-time-programmable EPROM (PIC16C56A) variants, with the "T" suffix denoting the tape-and-reel packaging option.
Key features include 12 I/O pins, 20 MHz maximum oscillator input, a 33-instruction RISC instruction set, on-chip power-on reset, watchdog timer with its own on-chip RC oscillator, internal MCLR reset input, programmable code protection, power-saving SLEEP mode, and selectable oscillator configurations (RC, LP, XT, HS, external clock). The 20 in the part number suffix designates the 20 MHz speed grade, the T denotes tape-and-reel, and /SO denotes the SOIC-18 wide-body small-outline package.
Typical applications span consumer appliances, automotive subsystems (non-safety), industrial control nodes, sensor interfaces, and low-cost battery-powered devices that benefit from deterministic single-cycle RISC execution and a mature toolchain based on MPLAB IDE and the MP3/MPLAB PM3 device programmer.
When designing with the PIC16C56AT-20/SO, ensure the Vdd decoupling network (typically 0.1 µF ceramic in parallel with a bulk tantalum/electrolytic cap) is placed within 10 mm of the supply pin, and respect the maximum I/O sink/source ratings per pin and per port.
Drop-in alternatives for PIC16C56AT-20/SO — 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 PIC16C56AT-20/SO (same form factor and footprint) — differing in Package, Timers, Mounting Type, Program Memory Type, Watchdog Timer.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C56AT-04E/SO
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$1.81 / Unit
View Datasheet →PIC16C56A-20I/SS
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$0.67 / Unit
View Datasheet →PIC16C56A-20E/P
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$2.85 / Unit
View Datasheet →PIC16C56A-04E/P
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$1.21 / Unit
View Datasheet →PIC16C55AT-20/SO
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$1.45 / Unit
View Datasheet →PIC16C56AT-20/SO Maximum Ratings & Electrical Characteristics
| Core Architecture | 8-bit RISC, Harvard |
| Family | PIC16C5X (PIC16C56A sub-family) |
| Program Memory Type | OTP EPROM |
| Program Memory Size | 1.5 KB (1K x 12) |
| Data RAM | 25 bytes |
| Maximum Clock Frequency | 20 MHz |
| Instruction Set Size | 33 instructions |
| Instruction Width | 12 bits |
| I/O Pins | 12 |
| Timers | 1 x 8-bit (TMR0) with watchdog |
| Interrupts | External edge-selectable (PIC16C56A sub-family) |
| Watchdog Timer | Yes, with dedicated on-chip RC oscillator |
| Power-on Reset | Yes, on-chip |
| Power-Saving Mode | SLEEP |
| Code Protection | Programmable, on-chip |
| Oscillator Modes | RC, LP, XT, HS, External Clock |
| Temperature Grade | Commercial |
| Package | 18-lead SOIC ("SO"), gull-wing |
| Mounting Type | Surface Mount |
| Lead Form | Gull Wing |
PIC16C56AT-20/SO Pin Configuration
| Pin 1 | RA2/AN2 — Bidirectional I/O / analog channel (PIC16C56A) |
| Pin 2 | RA3/AN3 — Bidirectional I/O / analog channel (PIC16C56A) |
| Pin 3 | T0CKI — Timer0 external clock input |
| Pin 4 | MCLR/Vpp — Master clear reset (active low) / programming voltage input |
| Pin 5 | Vss — Ground reference |
| Pin 6 | RB0/INT — Bidirectional I/O / external interrupt input |
| Pin 7 | RB1 — Bidirectional I/O |
| Pin 8 | RB2 — Bidirectional I/O |
| Pin 9 | RB3 — Bidirectional I/O |
| Pin 10 | RB4 — Bidirectional I/O |
| Pin 11 | RB5 — Bidirectional I/O |
| Pin 12 | RB6 — Bidirectional I/O |
| Pin 13 | RB7 — Bidirectional I/O |
| Pin 14 | OSC2/CLKO — Oscillator crystal output / clock output |
| Pin 15 | OSC1/CLKI — Oscillator crystal input / external clock input |
| Pin 16 | RC0 — Bidirectional I/O (PIC16C56A additional port) |
| Pin 17 | RC1 — Bidirectional I/O (PIC16C56A additional port) |
| Pin 18 | Vdd — Positive supply voltage |
Typical Applications
PIC16C56AT-20/SO is suitable for 6 applications: Consumer Appliance Control, Automotive Body Electronics (Non-Safety), Industrial Sensor Interface Module, Remote Control and Toy Electronics, LED Lighting Controllers, Battery-Powered Sensor Nodes.
Consumer Appliance Control
The PIC16C56AT-20/SO is well suited to consumer appliance control boards - washing machines, microwave ovens, coffee makers, dishwashers - where deterministic single-cycle RISC execution, 12 I/O pins, and a 20 MHz instruction throughput of 5 MIPS provide ample headroom for keypad scanning, relay drivers, and simple user-interface state machines. The 1.5 KB OTP program memory accommodates typical appliance firmware (mode selection, timing, fault handling) without external memory, and the on-chip watchdog timer plus power-on reset simplify fail-safe design for unattended equipment. The SOIC-18 surface-mount package supports automated pick-and-place assembly at the volumes typical of white-goods manufacturing.
Recommended
Automotive Body Electronics (Non-Safety)
In automotive body electronics applications such as interior lighting controllers, mirror-adjust modules, seat-position memory, and simple body-control nodes, the PIC16C56AT-20/SO delivers 12 I/O lines and 5 MIPS throughput suitable for low-rate CAN/LIN companion tasks when paired with a dedicated transceiver. The 20 MHz oscillator and edge-selectable external interrupts (a PIC16C56A feature) support precise debouncing of mechanical switch inputs. Note that this part is commercial-temperature-grade and is not qualified to AEC-Q100; for safety-relevant or under-hood modules select a PIC16F1XXX or PIC18 K-series AEC-Q100-qualified MCU instead.
Recommended
Industrial Sensor Interface Module
For industrial sensor-interface modules - simple 4-20 mA loop conditioners, digital thermocouple readers, limit-switch multiplexers, and panel-meter driver boards - the PIC16C56AT-20/SO provides 12 GPIO for matrix keypad or LED segment driving, a hardware watchdog for unattended operation, and a 33-instruction RISC set that compiles small and deterministic code. The 1.5 KB OTP holds linearization tables and modest protocol stacks. Industrial users should note the commercial temperature grade; for -40 to +85C environments the PIC16C56AT-20I/SO industrial variant is required.
Recommended
Remote Control and Toy Electronics
Low-cost remote controls, RC toys, and hobbyist electronics benefit from the PIC16C56AT-20/SO's small SOIC-18 footprint, 12 I/O for matrix keypads or LED indicators, and 20 MHz throughput for IR carrier generation and simple PWM motor control. The on-chip watchdog and SLEEP mode extend battery life in handheld devices, while OTP program memory keeps unit cost low for high-volume consumer goods. Designers can move to the flash-based PIC16F54 for prototype reuse without changing the PCB layout.
Recommended
LED Lighting Controllers
Addressable LED strip controllers, decorative lighting drivers, and DMX-512 node electronics can use the PIC16C56AT-20/SO as a low-cost sequencing engine. The 5 MIPS instruction throughput is more than adequate for WS2812/NeoPixel bit-banging at 800 kHz, and the 12 I/O accommodate a small DIP-switch address selector plus the LED data line. The on-chip watchdog timer is useful for unattended decorative installations. The SOIC-18 package simplifies integration into the small PCBs typical of LED fixtures.
Recommended
Battery-Powered Sensor Nodes
For battery-powered sensor nodes such as simple wireless push-buttons, thermostats, and environmental loggers, the PIC16C56AT-20/SO offers a hardware SLEEP mode and on-chip watchdog timer that together minimize quiescent current between samples. The 12 I/O connect to low-power sensors and an RF transmitter such as a sub-GHz OOK module. The 20 MHz oscillator can be swapped for the LP oscillator mode at 32.768 kHz for ultra-low-power timekeeping, and 1.5 KB OTP is sufficient for small sensor-fusion and duty-cycle control firmware.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C56AT-20/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C56AT-04E/SO | PIC16C55AT-20/SO | PIC16C56A-20I/SS | PIC16C56A-20E/P |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | SOIC-18 (/SO) | SOIC-18 - same | SOIC-18 - same | SSOP-20 (different footprint) | PDIP-18 (through-hole, different footprint) |
| Core / Family | PIC16C56A (8-bit RISC, PIC16C5X) | PIC16C56A (same) | PIC16C55A (sister family) | PIC16C56A (same) | PIC16C56A (same) |
| Program Memory | 1.5 KB OTP (1K x 12) | 1.5 KB OTP (same) | 1.5 KB OTP (same) | 1.5 KB OTP (same) | 1.5 KB OTP (same) |
| Data RAM | 25 bytes | 25 bytes | 25 bytes | 25 bytes | 25 bytes |
| Maximum Clock Frequency | 20 MHz | 4 MHz (-04 speed grade) | 20 MHz | 20 MHz | 20 MHz |
| I/O Pins | 12 | 12 | 13 | 13 | 13 |
| On-chip Analog Comparator | No | No | Yes | No | No |
| Temperature Grade | Commercial | Extended (-40 to +125 C) | Commercial | Industrial (-40 to +85 C) | Extended (-40 to +125 C) |
Key Differentiators
- SOIC-18 surface-mount variant of the PIC16C56A sub-family (vs PIC16C56A-20E/P (PDIP-18))
- Edge-selectable external interrupt and additional 8-bit I/O port (vs PIC16C56 (legacy))
- 20 MHz speed grade for 5 MIPS instruction throughput (vs PIC16C56AT-04E/SO (4 MHz speed grade))
Design Notes
Estimated: place a 0.1 uF ceramic decoupling capacitor within 5-10 mm of the Vdd pin (pin 18) and a bulk capacitor of 1-10 uF (tantalum or electrolytic) on the same supply rail. The PIC16C56AT-20/SO draws a few mA active and a few uA in SLEEP mode, so the bulk capacitor must sustain Vdd through any expected SLEEP duty cycle. Tie MCLR (pin 4) to Vdd through a 10 kohm pull-up; if external reset is not used, leave the MCLR pin connected to Vdd directly. Add a small-signal diode from MCLR to Vdd if inductive kickback is possible on the reset line.
Estimated: keep oscillator traces short and surround them with a grounded copper pour. Crystal or ceramic resonator loading capacitors (typically 15-33 pF) must be placed within a few millimeters of OSC1 (pin 15) and OSC2 (pin 14). For high-noise environments, place the device away from switching power and signal lines, and add a ground guard ring around the oscillator section. The SOIC-18 footprint leaves adequate room for via-in-pad stitching to the inner ground plane; populate at least two ground stitches directly under the SOIC paddle area for thermal relief.
Estimated: do not program the PIC16C56AT-20/SO with PIC16C56 firmware without verifying the I/O port and interrupt mapping; the PIC16C56A sub-family adds an extra 8-bit I/O port (RC) and edge-selectable interrupts that the legacy PIC16C56 lacks. The OTP device cannot be erased by UV light, so firmware development must use a windowed (JW) package or a flash-based PIC16F54/55 development board. Confirm the toolchain you plan to use supports the PIC16C56A silicon revision; older MPASM / MPLAB IDE 8.x project files may need updating to the latest MPLAB X IDE for current toolchain support.
Estimated: SOIC-18 packages have a typical theta_JA of approximately 70-90 C/W on a standard 4-layer JEDEC test board. At the modest 5 V supply and 20 MHz clock typical for PIC16C56AT-20/SO designs, total device dissipation is well under 100 mW, so the junction temperature rise above ambient is negligible (<10 C) and no heatsink is required. Industrial users should still verify that operating ambient plus worst-case self-heating remains inside the commercial (0-70 C) or industrial (-40 to +85 C) limit of the chosen speed grade.
Compliance Information
RoHS, REACH, lead-free, halogen-free, and conflict-minerals status for PIC16C56AT-20/SO were not present in the verified web data; treat each as 'unknown' until confirmed with the manufacturer or distributor. The part is not AEC-Q100 qualified; for safety-relevant automotive designs select an AEC-Q100-qualified PIC16F or PIC18 K-series MCU instead.
