PIC16F873A-E/ML - 8-Bit 20MHz MCU 7KB Flash 28-QFN | Microchip
MPN: PIC16F873A-E/ML ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $6.4 | $6.40 |
| 10 | $5.78 | $57.80 |
| 100 | $4.92 | $492.00 |
| 500 | $4.05 | $2,025.00 |
| 1,000 | $3.35 | $3,350.00 |
PIC16F873A-E/ML Overview
A microcontroller (MCU) is a single-chip computer that integrates a CPU core, non-volatile program memory, working RAM, and configurable peripherals such as timers, ADCs, communication interfaces, and general-purpose I/O. The PIC16F873A belongs to Microchip's mid-range PIC16 family, sitting architecturally between the baseline PIC10/PIC12/PIC16 and the high-performance PIC18/PIC24 families. The device is fully upwards-compatible with the PIC16C5X, PIC12CXXX, and PIC16C7X lines, and shares its instruction set and pinout philosophy with the PIC16F874A/876A/877A siblings, allowing easy migration to larger-pin-count variants when more I/O is needed.
Key features include 22 digital I/O pins, 5 channels of 10-bit ADC, 2 analog comparators, a synchronous serial port configurable as SPI or I2C, a USART for asynchronous serial, two 8-bit timers plus one 16-bit timer, nanoWatt power management, and In-Circuit Debug (ICD) plus self-programming capability. The PIC16F873A is a member of Microchip's "Enhanced Flash Microcontrollers" family featuring nanoWatt Technology for reduced quiescent current in sleep and idle modes.
Typical applications include automotive body electronics and HVAC controls, industrial sensor interfacing, low-cost consumer appliance control, sensor signal conditioning with on-chip ADC, and battery-powered remote nodes that benefit from nanoWatt sleep modes. The wide operating voltage range of 4.0 V to 5.5 V and robust 20 MHz throughput suit 5V-system designs.
When designing with the PIC16F873A-E/ML, ensure a solid thermal pad solder connection to a copper pour (typically 1 sq. inch minimum) for heat spreading, since the exposed pad (EP) is the primary thermal path. Decoupling: place a 100 nF ceramic capacitor within 5 mm of each VDD/VSS pair and a bulk 10 uF near the supply pin.
Drop-in alternatives for PIC16F873A-E/ML — 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 PIC16F873A-E/ML (same form factor and footprint) — differing in Package, Core Architecture, Serial Interfaces, Timers, ADC.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16F873A-I/ML
✅ Drop-In✓ In Stock
$2.32 / Unit
View Datasheet →PIC16F873AT-I/ML
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16F876A-I/ML
✅ Drop-In✓ In Stock
$5.4 / Unit
View Datasheet →PIC16F876A-E/ML
✅ Drop-In✓ In Stock
$4.85 / Unit
View Datasheet →PIC16F873AT-E/ML
✅ Drop-In✓ In Stock
$4.45 / Unit
View Datasheet →PIC16F1824-I/ML
✅ Drop-In✓ In Stock
$1.18 / Unit
View Datasheet →PIC16F873A-E/ML Maximum Ratings & Electrical Characteristics
| Series | PIC 16F |
| Core Processor | PIC |
| Core Size | 8-Bit |
| Maximum Clock Speed | 20 MHz |
| Instruction Cycle Time | 200 ns |
| Program Memory Size | 7 KB (4K x 14 words) FLASH |
| RAM Size | 192 bytes |
| EEPROM Size | 128 bytes |
| Number of I/O Pins | 22 |
| Supply Voltage Range | 4.0 V to 5.5 V |
| ADC | 10-bit, 5 channels |
| Comparators | 2 |
| Timers | 2 x 8-bit, 1 x 16-bit |
| Communication Interfaces | SPI, I2C, USART |
| Package | 28-QFN (6x6 mm) with Exposed Pad |
| Operating Temperature Range | -40C to +125C (Extended, "-E" grade) |
| Mounting Type | Surface Mount |
| Mounting Style | SMD/SMT |
| Terminal Form | No Lead |
| Package Code | VQCCN (QFN-28) |
| RoHS Status | Compliant |
| Data Flash/EEPROM | 128 bytes |
| Program Memory Type | Flash |
| Peripheral Features | Brown-out Detect, ICD, POR, PWM, WDT, nanoWatt Technology |
PIC16F873A-E/ML Pin Configuration
| Pin 1 | MCLR/VPP — Master Clear (reset) input / programming voltage input |
| Pin 2 | RA0/AN0 — Port A bit 0 / Analog input 0 |
| Pin 3 | RA1/AN1 — Port A bit 1 / Analog input 1 |
| Pin 4 | RA2/AN2/VREF-/CVREF — Port A bit 2 / Analog input 2 / DAC negative reference / comparator voltage reference output |
| Pin 5 | RA3/AN3/VREF+ — Port A bit 3 / Analog input 3 / DAC positive reference |
| Pin 6 | RA4/T0CKI/C1OUT — Port A bit 4 / Timer 0 clock input / Comparator 1 output |
| Pin 7 | RA5/AN4/SS/C2OUT — Port A bit 5 / Analog input 4 / SPI slave select / Comparator 2 output |
| Pin 8 | VSS — Ground reference |
| Pin 9 | OSC1/CLKIN — Oscillator crystal input / external clock input |
| Pin 10 | OSC2/CLKOUT — Oscillator crystal output / clock output |
| Pin 11 | RC0/T1OSO/T1CKI — Port C bit 0 / Timer 1 oscillator output / Timer 1 clock input |
| Pin 12 | RC1/T1OSI/CCP2 — Port C bit 1 / Timer 1 oscillator input / Capture-Compare-PWM 2 |
| Pin 13 | RC2/CCP1 — Port C bit 2 / Capture-Compare-PWM 1 |
| Pin 14 | RC3/SCK/SCL — Port C bit 3 / SPI clock / I2C clock |
| Pin 15 | RC4/SDI/SDA — Port C bit 4 / SPI data in / I2C data |
| Pin 16 | RC5/SDO — Port C bit 5 / SPI data out |
| Pin 17 | RC6/TX/CK — Port C bit 6 / USART async transmit / USART sync clock |
| Pin 18 | RC7/RX/DT — Port C bit 7 / USART async receive / USART sync data |
| Pin 19 | VSS — Ground reference |
| Pin 20 | VDD — Positive supply voltage (4.0 V to 5.5 V) |
| Pin 21 | RB0/INT — Port B bit 0 / External interrupt |
| Pin 22 | RB1 — Port B bit 1 |
| Pin 23 | RB2 — Port B bit 2 |
| Pin 24 | RB3/PGM — Port B bit 3 / Low-voltage programming input |
| Pin 25 | RB4 — Port B bit 4 |
| Pin 26 | RB5/PGM — Port B bit 5 |
| Pin 27 | RB6/PGC — Port B bit 6 / In-Circuit Debugger clock |
| Pin 28 | RB7/PGD — Port B bit 7 / In-Circuit Debugger data |
Typical Applications
PIC16F873A-E/ML is suitable for 6 applications: Automotive Body Electronics, Industrial Sensor Interface Modules, Low-Cost Consumer Appliance Control, Battery-Powered Remote Sensor Nodes, HVAC Damper and Valve Actuators, Educational and Prototyping Boards.
Automotive Body Electronics
The PIC16F873A-E/ML's Extended -40C to +125C temperature grade and nanoWatt Technology make it a strong fit for automotive body controllers such as seat-position modules, mirror adjusters, and HVAC flap drivers. Its 5-channel 10-bit ADC reads thermistor inputs and potentiometer wiper positions, while the 22 I/O pins drive relays, FET gates, and LED indicators. Compared with the PIC16F873A-I/ML (Industrial grade only), the -E/ML part survives under-hood thermal stress. The 7 KB Flash with self-programming supports field firmware updates via OBD-II.
Recommended
Industrial Sensor Interface Modules
In 4-20 mA loop-powered sensor transmitters and bridge-amplifier signal conditioners, the PIC16F873A-E/ML digitizes analog sensor outputs through its 10-bit ADC and communicates results over USART/RS-485 to a PLC. The Extended temperature grade supports factory-floor and outdoor installations, and the nanoWatt sleep mode reduces quiescent current to a few microamps for loop-powered designs. SPI or I2C can drive an external EEPROM or DAC for calibration storage.
Recommended
Low-Cost Consumer Appliance Control
The PIC16F873A-E/ML targets small appliances like coffee makers, washing machines, and microwave ovens where its 5-channel ADC reads temperature sensors and potentiometers, its PWM drives motor/relay control, and its 22 I/O pins handle keypads and seven-segment displays. The 7 KB Flash fits compact state-machine code while the Extended temperature grade tolerates the heat inside enclosures. I2C connects to EEPROM for user settings.
Recommended
Battery-Powered Remote Sensor Nodes
For battery or energy-harvesting wireless sensor nodes, the PIC16F873A-E/ML's nanoWatt sleep modes drop quiescent current below typical sensing thresholds, extending coin-cell life to years. The USART or SPI drives sub-GHz radios (e.g., MRF89XA), the 10-bit ADC reads sensors on wake-up, and the 128-byte EEPROM stores calibration. The Extended temperature grade supports outdoor/unheated deployments.
Recommended
HVAC Damper and Valve Actuators
In HVAC damper and zone-valve actuators, the PIC16F873A-E/ML's 16-bit timer drives accurate PWM for proportional servo control while the 2 on-chip comparators implement over-current protection without external parts. The Extended temperature grade handles plenum-chamber heat. The 7 KB Flash supports proportional-integral control loops; I2C interfaces to an external temperature/humidity sensor.
Recommended
Educational and Prototyping Boards
The PIC16F873A-E/ML is widely used in university embedded-systems courses and hobbyist PIC programmer projects because its 28-QFN package is supported by Microchip's PICkit programmers, MPLAB X IDE, and XC8 compiler. The 35-instruction mid-range set is easy to teach; 7 KB Flash fits complete student projects; and the In-Circuit Debugger (ICD) interface allows real-time breakpoints without extra hardware.
Recommended
Recommended Products Summary
Engineering reference data for PIC16F873A-E/ML — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16F873A-I/ML | PIC16F873AT-I/ML | PIC16F876A-I/ML | PIC16F876A-E/ML | PIC16F873AT-E/ML | PIC16F1824-I/ML |
|---|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-QFN (6x6 mm) with EP | 28-QFN (6x6 mm) with EP - same | 28-QFN (6x6 mm) with EP - same | 28-QFN (6x6 mm) with EP - same | 28-QFN (6x6 mm) with EP - same | 28-QFN (6x6 mm) with EP - same | 28-QFN (6x6 mm) with EP - same |
| Program Memory (Flash) | 7 KB (4K x 14) | 7 KB - same | 7 KB - same | 14 KB (+100%) | 14 KB (+100%) | 7 KB - same | 8 KB (+14%) |
| RAM Size | 192 B | 192 B - same | 192 B - same | 368 B (+92%) | 368 B (+92%) | 192 B - same | 256 B (+33%) |
| EEPROM Size | 128 B | 128 B - same | 128 B - same | 256 B (+100%) | 256 B (+100%) | 128 B - same | 256 B (+100%) |
| Max Clock Speed | 20 MHz | 20 MHz - same | 20 MHz - same | 20 MHz - same | 20 MHz - same | 20 MHz - same | 32 MHz (+60% via PLL) |
| Supply Voltage | 4.0 V to 5.5 V | 4.0 V to 5.5 V - same | 4.0 V to 5.5 V - same | 4.0 V to 5.5 V - same | 4.0 V to 5.5 V - same | 4.0 V to 5.5 V - same | 1.8 V to 5.5 V (wider) |
| Temperature Grade | Extended (-40C to +125C) | Industrial (-40C to +85C) | Industrial (-40C to +85C) | Industrial (-40C to +85C) | Extended (-40C to +125C) - same | Extended (-40C to +125C) - same | Industrial (-40C to +85C) |
| Instruction Set | PIC16 mid-range (35 instructions) | PIC16 mid-range (35 instructions) - same | PIC16 mid-range (35 instructions) - same | PIC16 mid-range (35 instructions) - same | PIC16 mid-range (35 instructions) - same | PIC16 mid-range (35 instructions) - same | Enhanced mid-range (49 instructions) |
Key Differentiators
- Extended -40C to +125C temperature grade for harsh environments (vs PIC16F873A-I/ML)
- Double the Flash memory with same footprint (vs PIC16F876A-E/ML)
- Enhanced mid-range core with more peripherals (vs PIC16F1824-I/ML)
Design Notes
The 28-QFN package relies on the exposed thermal pad (EP) as the primary thermal path. For high-temperature Extended-grade (-E) applications, the EP must be soldered to a copper pour of at least 1 sq. inch with multiple thermal vias to the inner/outer ground plane. Without proper EP soldering, junction temperature can exceed 125C at moderate ambient temperatures. Estimated: at 20 MHz with all peripherals active, IDD ~ 10 mA at 5 V, dissipating only 50 mW; thermal concerns are mainly from self-heating of nearby passives, not the MCU itself.
Place a 100 nF ceramic decoupling capacitor within 5 mm of each VDD/VSS pair (pins 20/8 and pins 27/19). Add a bulk 10 uF tantalum or ceramic near the supply entry point. Keep the oscillator traces (OSC1/OSC2) short and shielded by a ground guard ring to reduce EMI susceptibility. Route the ICSP signals PGC/PGD (RB6/RB7) on the same layer to the programming header without vias in the path.
Common pitfalls with PIC16F873A-E/ML designs include: (1) leaving MCLR floating - always tie MCLR to VDD through a 10 kohm resistor for proper reset, (2) using an analog pin as digital input without disabling the ADC via ADCON1, which can cause floating reads, (3) exceeding 5.5 V on any pin including ADC inputs, which can damage the part. The brown-out detect (BOR) and watchdog timer (WDT) should be enabled in safety-critical applications via the configuration bits.
For QFN-28 layout, use 0.4 mm pitch pads with a non-solder-mask-defined (NSMD) land pattern for best solder joint reliability. The center EP pad should have multiple thermal vias (typically 9-12, 0.3 mm diameter) connecting top copper to an inner ground layer. Per IPC-7351 nominal land dimensions, pad width 0.20 mm and length 0.40 mm for the perimeter pads. Avoid placing components within 2 mm of the EP copper pour to maintain thermal isolation.
Compliance Information
RoHS and REACH compliance per Microchip product page. AEC-Q100 qualification status is not explicitly listed on Microchip's standard product page for PIC16F873A-E/ML; contact Microchip for automotive-grade variants such as PIC16F873A-E/MLVAO if AEC-Q100 documentation is required.
