PIC16C73A-20/SP - 8-bit 20MHz MCU 7KB OTP 28-SPDIP | Microchip
MPN: PIC16C73A-20/SP ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $9.88 | $9.88 |
| 10 | $9.1 | $91.00 |
| 100 | $8.45 | $845.00 |
| 500 | $7.85 | $3,925.00 |
| 1,000 | $7.2 | $7,200.00 |
PIC16C73A-20/SP Overview
An 8-bit microcontroller (microcontroller IC) is a single-chip computer that integrates a CPU, memory, and peripherals. The PIC16C73A belongs to the PIC16C family, part of the PIC® mid-range microcontroller family, which itself falls under the broader category of microcontrollers -> microcomputer ICs -> embedded processors -> semiconductors. The PIC16C7X line was designed as low-cost, high-performance, fully-static CMOS 8-bit microcontrollers with on-chip ADC.
Key features include a high-performance RISC CPU with only 35 single-word instructions, all single-cycle except program branches (two cycles), wide operating voltage range up to 6.0V, 25/25 mA high sink/source current on I/O pins, and very low power consumption (5 mA typical at 5V/4 MHz and 1 µA typical standby at 3V/32 kHz). The integrated 8-bit ADC and 22 I/O pins enable direct interfacing to analog sensors and digital peripherals.
The device uses a Harvard architecture with separate program and data paths. The 7KB OTP (one-time programmable EPROM) memory holds firmware, while 192 bytes of RAM store volatile data. Three timer/counters, a synchronous serial port (SSP) for SPI/I2C, a USART, capture/compare/PWM module, and an 8-channel 8-bit ADC are integrated on-chip, reducing external component count.
Typical applications include industrial control systems, automotive body electronics, motor control, sensor signal conditioning, and embedded control in appliances. The integrated ADC suits direct analog sensor interfaces, and the 22 I/O lines accommodate keyboards, displays, and relay drivers.
When designing with this device, ensure OTP programming is performed before final assembly as the memory cannot be erased. For prototyping, the windowed CERDIP variant allows UV erasure. Decoupling capacitors of 0.1 µF near VDD and a bulk capacitor near the IC are recommended. Watchdog timer should be enabled for unattended reset recovery.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for PIC16C73A-20/SP — 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 PIC16C73A-20/SP (same form factor and footprint) — differing in Package, Timers, Program Memory Size, Mounting Type, Program Memory Type.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C73B-20/SP
✅ Drop-In✓ In Stock
$4.95 / Unit
View Datasheet →PIC16C73A-10/SP
✅ Drop-In✓ In Stock
$6.4 / Unit
View Datasheet →PIC16C73A-20E/SP
✅ Drop-In✓ In Stock
$6.75 / Unit
View Datasheet →PIC16C73A-04/SP
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C72-20/SP
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$2.95 / Unit
View Datasheet →PIC16C74A-20/SP
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C73A-20/SP Maximum Ratings & Electrical Characteristics
| Core Processor | PIC |
| Core Size | 8-Bit |
| Speed | 20 MHz |
| Program Memory Size | 7 KB (4K x 14) OTP |
| RAM Size | 192 x 8 |
| Number of I/O | 22 |
| Supply Voltage | 4.0 V to 5.5 V |
| Operating Temperature | 0C to +70C |
| Package | 28-SPDIP (0.300 inch, 7.62 mm) |
| Mounting Type | Through-Hole |
| ADC Resolution | 8-bit |
| ADC Channels | 5 |
| ROM Type | OTP (UV-erasable windowed CERDIP for prototyping) |
| Number of Instructions | 35 (single word) |
| I/O Sink/Source Current | 25 mA / 25 mA |
| Timers | 3 x 8/16-bit |
| Connectivity | I2C, SPI, UART/USART |
| Peripherals | Brown-out Detect/Reset, POR, PWM, WDT |
| Oscillator Type | External |
| EEPROM Size | None |
PIC16C73A-20/SP Pin Configuration
| Pin 1 | MCLR/VPP — Master Clear (Reset) input / Programming voltage |
| Pin 2 | RA0/AN0 — Digital I/O / Analog input channel 0 |
| Pin 3 | RA1/AN1 — Digital I/O / Analog input channel 1 |
| Pin 4 | RA2/AN2 — Digital I/O / Analog input channel 2 |
| Pin 5 | RA3/AN3/VREF — Digital I/O / Analog input 3 / ADC VREF |
| Pin 6 | RA4/T0CKI — Digital I/O / Timer 0 clock input |
| Pin 7 | RA5/AN4/SS — Digital I/O / Analog input 4 / SPI slave select |
| Pin 8 | OSC2/CLKOUT — Oscillator output / Clock out |
| Pin 9 | OSC1/CLKIN — Oscillator input / External clock in |
| Pin 10 | RC0/T1OSO/T1CKI — Digital I/O / Timer 1 oscillator output |
| Pin 11 | RC1/T1OSI/CCP1TX — Digital I/O / Timer 1 oscillator in / PWM output |
| Pin 12 | RC2/CCP1 — Digital I/O / Capture/Compare/PWM 1 |
| Pin 13 | RC3/SCK/SCL — Digital I/O / SPI clock / I2C clock |
| Pin 14 | RC4/SDI/SDA — Digital I/O / SPI data in / I2C data |
| Pin 15 | RC5/SDO — Digital I/O / SPI data out |
| Pin 16 | RC6/TX/CK — Digital I/O / USART TX / USART clock |
| Pin 17 | RC7/RX/DT — Digital I/O / USART RX / USART data |
| Pin 18 | VSS — Ground reference |
| Pin 19 | VDD — Positive supply voltage |
| Pin 20 | RB0/INT — Digital I/O / External interrupt |
| Pin 21 | RB1 — Digital I/O |
| Pin 22 | RB2 — Digital I/O |
| Pin 23 | RB3/PGM — Digital I/O / Low-voltage programming |
| Pin 24 | RB4 — Digital I/O |
| Pin 25 | RB5 — Digital I/O |
| Pin 26 | RB6/PGC — Digital I/O / ICSP clock |
| Pin 27 | RB7/PGD — Digital I/O / ICSP data |
| Pin 28 | VSS — Ground reference |
Typical Applications
PIC16C73A-20/SP is suitable for 6 applications: Industrial Process Control Systems, Automotive Body Electronics, HVAC Control and Thermostat, Appliance Motor Control, Security and Alarm Panels, Medical Monitoring Equipment.
Industrial Process Control Systems
The PIC16C73A-20/SP fits industrial process control where its 5-channel 8-bit ADC directly digitizes sensor signals (temperature, pressure, flow) without external ADC ICs, reducing BOM cost and PCB area. With 20 MHz operation (5 MIPS), it executes PID control loops with adequate margin, while 22 digital lines interface relays, contactors, and indicator LEDs at 25 mA sink/source. The brown-out reset and watchdog timer ensure unattended recovery from power glitches, critical for 24/7 industrial deployment.
Recommended
Automotive Body Electronics
In automotive body modules (window lifts, mirror controls, lighting), the PIC16C73A-20/SP's 25 mA I/O drive directly switches incandescent lamps and small relays without driver transistors, saving cost. Its 4-5.5V supply range tolerates automotive 12V battery transients when paired with a 5V regulator. The integrated PWM module provides software-controlled dimming for interior lighting. However, note this part is NRND - new automotive designs should migrate to PIC16F73 or AEC-Q100 qualified PIC16F873A.
Recommended
HVAC Control and Thermostat
The PIC16C73A-20/SP is well-suited for HVAC thermostat controllers where its ADC reads thermistor or RTD temperature sensors while its PWM output drives TRIAC-based heater/coolant actuators. At 20 MHz, it can multiplex several temperature zones and run display refresh concurrently without missing real-time events. The 192-byte RAM accommodates modest control algorithms, and 7KB OTP stores calibration tables. Low standby (1 µA at 32 kHz) extends battery life in wireless thermostat designs.
Recommended
Appliance Motor Control
For washing machines, dishwashers, and small appliance motor control, the PIC16C73A-20/SP provides the on-chip PWM and capture/compare peripherals needed for closed-loop motor commutation without external timer ICs. Its 20 MHz clock supports sensorless or Hall-effect BLDC/PMSM algorithms for low-voltage fans and pumps. 22 I/O pins handle keypad input, LCD output, and motor enable signals. OTP memory protects firmware from accidental field tampering.
Recommended
Security and Alarm Panels
The PIC16C73A-20/SP serves wired alarm panel controllers, with its ADC monitoring battery voltage and analog sensor loops (smoke detectors, PIR analog front-ends). The USART enables connection to central station dialers or keypad modules, while the SSP supports I2C/SPI peripherals like EEPROM (for event log storage) and real-time clocks. Brown-out reset and watchdog timer ensure reliable recovery from brown-out and EMI-induced lockups.
Recommended
Medical Monitoring Equipment
In low-end medical devices such as digital thermometers, blood pressure monitors, and pulse oximeters, the PIC16C73A-20/SP's 8-bit ADC digitizes sensor signals with adequate resolution for diagnostic-grade accuracy. Its low standby current (1 µA) extends battery life in portable designs, while 22 I/O pins drive LCD displays, button interfaces, and alarm buzzers. Designers must validate IEC 60601 compliance separately; for new medical IEC 62304 lifecycle development, migrate to PIC16F73 or PIC24+.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C73A-20/SP — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C73B-20/SP | PIC16C73A-10/SP | PIC16C73A-20E/SP | PIC16C73A-04/SP | PIC16C72-20/SP |
|---|---|---|---|---|---|---|
| Package | 28-SPDIP (0.300 inch) | 28-SPDIP (0.300 inch) - same | 28-SPDIP (0.300 inch) - same | 28-SPDIP (0.300 inch) - same | 28-SPDIP (0.300 inch) - same | 28-SPDIP (0.300 inch) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Program Memory | 7 KB OTP | 7 KB OTP | 7 KB OTP | 7 KB OTP | 7 KB OTP | 7 KB OTP |
| Clock Speed | 20 MHz | 20 MHz | 10 MHz | 20 MHz | 4 MHz | 20 MHz |
| ADC | 8-bit, 5 channels | 8-bit, 5 channels | 8-bit, 5 channels | 8-bit, 5 channels | 8-bit, 5 channels | None |
| RAM Size | 192 bytes | 192 bytes | 192 bytes | 192 bytes | 192 bytes | 192 bytes |
| Operating Temperature | 0C to +70C (Commercial) | 0C to +70C | 0C to +70C | -40C to +125C (Extended) | 0C to +70C | 0C to +70C |
| Lifecycle Status | NRND | Active (recommended) | NRND | NRND | NRND | NRND |
Key Differentiators
- Integrated 8-bit ADC with 5 channels eliminates external ADC IC (vs PIC16C72-20/SP)
- PIC16C73B is Microchip's officially recommended successor with bug fixes (vs PIC16C73B-20/SP)
- Extended temperature variant available with same pinout (vs PIC16C73A-20E/SP)
Design Notes
Place a 0.1 µF ceramic decoupling capacitor as close as possible to pin 19 (VDD) and pin 28 (VSS), with a bulk 10 µF tantalum or aluminum capacitor on the same supply rail within 1 inch. For noise-sensitive ADC applications, add a 10 µH inductor and additional 10 µF capacitor to form an LC pi-filter on VDD. This reduces digital switching noise coupling into analog VREF, improving ADC SNR by 6-10 dB.
The PIC16C73A-20/SP uses OTP (one-time programmable) memory - once programmed, firmware cannot be erased. For development, use the windowed CERDIP variant or the PIC16C73B (EPROM-based) or PIC16F73 (flash-based) instead. Field returns due to firmware bugs cannot be recovered in-circuit; ensure code is fully validated with the development part before committing to OTP programming for inventory.
For the 28-SPDIP package, allow at least 0.1 inch (2.54 mm) hole diameter for through-hole pins and use a 0.045 inch (1.14 mm) pad diameter. Place a ground pour on the bottom layer under the IC to provide thermal dissipation and EMI shielding. Keep clock traces (OSC1/OSC2) short and surrounded by ground pour to minimize radiated EMI, particularly when the IC drives external relays or PWM outputs.
When using the integrated ADC, connect AVSS to the same ground as VSS and use a star-ground topology to prevent digital return currents from corrupting analog readings. Place a 100 nF capacitor close to VREF pin if used externally. For accurate ADC readings, perform at least 10 µs of acquisition time on the sample-and-hold capacitor; configure ADC clock divider to ensure ADCS period falls within 1.6 µs minimum (TAD) per datasheet specification.
Compliance Information
Original PIC16C73A-20/SP is non-RoHS (windowed CERDIP, lead-bearing). RoHS-compliant equivalents are typically marked with /SLASH or /SO packages rather than the SPDIP windowed CERDIP /SP. AEC-Q100 qualification not applicable to this commercial-grade part; PIC16F873A is the AEC-Q100 qualified alternative for automotive.
