PIC16C73BT-04E/SS - 8-Bit 4MHz OTP MCU 7KB Flash | Microchip
MPN: PIC16C73BT-04E/SS ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $9.45 | $9.45 |
| 10 | $8.5 | $85.00 |
| 100 | $7.25 | $725.00 |
| 500 | $6.1 | $3,050.00 |
| 1,000 | $5.25 | $5,250.00 |
PIC16C73BT-04E/SS Overview
A microcontroller (MCU) is a single-chip computer that integrates a CPU core, program memory, working RAM, peripheral interfaces, and I/O lines on one silicon die. Microcontrollers sit at the bottom of the embedded computing hierarchy: microcontroller -> embedded processor -> computer-on-module. Within Microchip's portfolio, the PIC16C family is a mid-range 8-bit architecture with a 14-bit instruction word, positioned above the baseline PIC16C5x family but below the PIC18 8-bit extended family and the PIC24/dsPIC 16-bit families.
Key features of the PIC16C73BT-04E/SS include a 35-instruction RISC-style set, 4 MHz operation from a 4.0 V to 5.5 V single supply, on-chip Power-On Reset (POR), Brown-Out Reset (BOR), Watchdog Timer with its own on-chip RC oscillator, in-circuit serial programming via two pins, and an operating temperature range of -40 C to +125 C qualified under the "E" (extended) designation. The architecture uses Harvard-style separate program and data buses with 14-bit instructions and 8-bit data paths.
Typical applications include industrial control front-ends, sensor conditioning with the on-chip ADC, simple user-interface controllers with keypad and LCD scanning, low-speed UART-bridge gateways, and legacy automotive or appliance subsystems that retain a 28-pin 0.65 mm pitch SSOP socket. The wide temperature range and integrated peripherals make it suitable for factory-floor and white-goods designs where external components must be minimized for BOM cost reasons.
When designing with this part, note that OTP memory cannot be erased or rewritten, so firmware must be fully validated before programming. Designers targeting in-the-field firmware updates should consider the flash-based PIC16F73 sibling instead, which shares the same pinout and peripheral set but uses Flash program memory.
Drop-in alternatives for PIC16C73BT-04E/SS — 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 PIC16C73BT-04E/SS (same form factor and footprint) — differing in Package, Timers, Core Architecture, Operating Temperature, Maximum Clock Frequency.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C73B-04E/SS
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C73B-04/SS
✅ Drop-In✓ In Stock
$5.05 / Unit
View Datasheet →PIC16C73B-20/SS
✅ Drop-In✓ In Stock
$4.56 / Unit
View Datasheet →PIC16C73B-04I/SS
✅ Drop-In✓ In Stock
$1.4 / Unit
View Datasheet →PIC16C73BT-04E/SS Maximum Ratings & Electrical Characteristics
| Family | PIC16CXX mid-range |
| Core | 8-bit PIC16C |
| Instruction Word Width | 14 bits |
| Program Memory Type | OTP (One-Time Programmable) |
| Program Memory Size | 7 KB (4K x 14) |
| RAM Size | 192 bytes |
| EEPROM Size | 0 bytes (not present) |
| Maximum Clock Frequency | 4 MHz |
| Supply Voltage (Vdd) | 4.0 V to 5.5 V |
| Number of I/O Pins | 22 |
| ADC | 5 channels x 8-bit |
| Timers | 1 x 8-bit + 1 x 16-bit (TMR0/TMR1/TMR2) |
| Communication Interfaces | UART/USART, I2C, SPI (via MSSP) |
| Package | 28-SSOP (0.209 inch / 5.30 mm body width, 0.65 mm pitch) |
| Mounting Type | Surface Mount |
| Operating Temperature | -40 C to +125 C (extended, "E" suffix) |
| Watchdog Timer | Yes (with dedicated on-chip RC oscillator) |
| Brown-Out Reset | Yes |
| In-Circuit Programming | Yes (2-pin ICSP) |
| RoHS Status | Compliant |
PIC16C73BT-04E/SS Pin Configuration
| Pin 1 | MCLR/VPP — Master Clear (reset) input or programming voltage input |
| Pin 2 | RA0/AN0 — PORTA bit 0 / ADC input 0 |
| Pin 3 | RA1/AN1 — PORTA bit 1 / ADC input 1 |
| Pin 4 | RA2/AN2 — PORTA bit 2 / ADC input 2 |
| Pin 5 | RA3/AN3/VREF — PORTA bit 3 / ADC input 3 / external ADC reference |
| Pin 6 | RA4/T0CKI — PORTA bit 4 / Timer0 external clock input |
| Pin 7 | RA5/AN4/SS — PORTA bit 5 / ADC input 4 / SPI slave select |
| Pin 8 | VSS — Ground reference |
| Pin 9 | OSC1/CLKIN — Crystal oscillator input / external clock input |
| Pin 10 | OSC2/CLKOUT — Crystal oscillator output / clock output |
| Pin 11 | RC0/T1OSO/T1CKI — PORTC bit 0 / Timer1 oscillator output or clock input |
| Pin 12 | RC1/T1OSI/CCP2 — PORTC bit 1 / Timer1 oscillator input / CCP2 module |
| Pin 13 | RC2/CCP1 — PORTC bit 2 / Capture-Compare-PWM 1 output |
| Pin 14 | RC3/SCK/SCL — PORTC bit 3 / SPI clock / I2C clock |
| Pin 15 | RC4/SDI/SDA — PORTC bit 4 / SPI data in / I2C data |
| Pin 16 | RC5/SDO — PORTC bit 5 / SPI data out |
| Pin 17 | RC6/TX/CK — PORTC bit 6 / USART TX / synchronous clock |
| Pin 18 | RC7/RX/DT — PORTC bit 7 / USART RX / synchronous data |
| Pin 19 | VSS — Ground reference |
| Pin 20 | VDD — Positive supply voltage (4.0 V to 5.5 V) |
| Pin 21 | RB0/INT — PORTB bit 0 / external interrupt input |
| Pin 22 | RB1 — PORTB bit 1 |
| Pin 23 | RB2 — PORTB bit 2 |
| Pin 24 | RB3 — PORTB bit 3 |
| Pin 25 | RB4 — PORTB bit 4 (interrupt-on-change) |
| Pin 26 | RB5 — PORTB bit 5 (interrupt-on-change) |
| Pin 27 | RB6/PGC — PORTB bit 6 / ICSP clock |
| Pin 28 | RB7/PGD — PORTB bit 7 / ICSP data |
Typical Applications
PIC16C73BT-04E/SS is suitable for 7 applications: Industrial Sensor Front-End Controller, White-Goods and Appliance Control, Low-Speed UART-to-I2C Bridge, User Interface / Keypad and LCD Scanners, Automotive Body Electronics (Legacy Skus), Battery-Powered Remote Sensor Node, Educational and Training Platforms.
Industrial Sensor Front-End Controller
The PIC16C73BT-04E/SS is well matched to industrial sensor front-end nodes because its 5-channel 8-bit ADC reads thermistors, photocells, and 4-20 mA shunts directly, while its 4 MHz core comfortably runs Modbus-RTU polling, sensor linearization, and threshold detection. The 4.0 V to 5.5 V supply range pairs cleanly with 5 V industrial backplanes. The extended -40 C to +125 C grade meets IEC 60068 harsh-environment profiles for factory-floor cabinets, and the 28-SSOP package fits in compact DIN-rail sensor heads where horizontal space is constrained but soldering remains manageable.
Recommended
White-Goods and Appliance Control
In washing machines, dishwashers, and HVAC blower controls, the PIC16C73BT-04E/SS handles relay sequencing, keypad scanning, and triac zero-cross timing with deterministic latency. The integrated 16-bit TMR1 is well suited to mains-synchronized timing, while the MSSP port drives I2C temperature sensors and EEPROM parameter storage. OTP memory prevents field tampering with firmware, which is desirable for regulatory certification bodies. The wide -40 C to +125 C range covers appliance thermal soak profiles near heating elements and motor housings.
Recommended
Low-Speed UART-to-I2C Bridge
The PIC16C73BT-04E/SS is often deployed as a glue translator between a host UART and an I2C sensor cluster in industrial gateways. Its enhanced USART and MSSP modules run concurrently with no additional firmware glue, and the 192-byte RAM is sufficient for command parsing. Because the part is OTP, the bridge firmware image is locked at production, reducing cybersecurity risk in fielded installations. The 4 MHz instruction cycle keeps firmware deterministic and shortens interrupt latency for serial echo applications.
Recommended
User Interface / Keypad and LCD Scanners
The 22 I/O of the PIC16C73BT-04E/SS can matrix-scan up to a 4x5 keypad directly or drive a character LCD in 4-bit mode with minimal external logic. The change-on-interrupt feature on PORTB enables keypad wake-ups without continuous polling, lowering average current in battery-backed panels. Designers use the 8-bit ADC for backlight dimming via a photodiode or potentiometer. The 28-SSOP package gives a compact controller PCB behind small human-machine interface modules.
Recommended
Automotive Body Electronics (Legacy Skus)
In long-lifecycle automotive body controllers such as mirror adjusters, seat switches, and HVAC blend-door modules, the PIC16C73BT-04E/SS remains in production and supplies the AEC-Q100-style thermal headroom of -40 C to +125 C. The 5-channel ADC reads NTC thermistors for cabin temperature, and the MSSP bus drives SPI CAN-transceiver standby controls. Note that the part itself is not formally AEC-Q100 qualified; for new automotive designs Microchip recommends the dsPIC33 or PIC18 families with explicit automotive certification.
Recommended
Battery-Powered Remote Sensor Node
Although not a low-power MCU by modern standards, the PIC16C73BT-04E/SS can be duty-cycled in sleep mode with the watchdog timer as a wake source for slow telemetry nodes transmitting every few minutes. Brown-out reset protects battery-discharge transients, and the integrated ADC reads battery voltage directly on a divider. The 4 MHz clock allows short wake-up bursts to capture and transmit readings before returning to sleep. OTP memory prevents accidental field reprogramming that could brick the sensor in remote locations.
Recommended
Educational and Training Platforms
Universities and embedded-training labs retain the PIC16C73BT-04E/SS on legacy development boards because its instruction set is well documented and the peripheral mapping is simple. Students exercise USART polling, MSSP-based I2C EEPROM reading, ADC sampling, and timer-driven interrupts all from one part. The 28-SSOP package is hand-solderable on breakout boards for prototyping without reflow equipment. Although Microchip has retired several older simulators, the part is still supported by MPLAB X IDE with the MPASMW toolchain.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C73BT-04E/SS — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C73B-04E/SS | PIC16C73B-04/SS | PIC16C73B-20/SS | PIC16C73B-04I/SS |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-SSOP (5.30 mm) | 28-SSOP (5.30 mm) - same | 28-SSOP (5.30 mm) - same | 28-SSOP (5.30 mm) - same | 28-SSOP (5.30 mm) - same |
| Maximum Clock Frequency | 4 MHz | 4 MHz | 4 MHz | 20 MHz | 4 MHz |
| Program Memory Type | OTP | OTP | OTP | OTP | OTP |
| Program Memory Size | 7 KB (4K x 14) | 7 KB (4K x 14) | 7 KB (4K x 14) | 7 KB (4K x 14) | 7 KB (4K x 14) |
| RAM Size | 192 bytes | 192 bytes | 192 bytes | 192 bytes | 192 bytes |
| Operating Temperature | -40 C to +125 C (extended, E) | -40 C to +125 C (E) | 0 C to +70 C (commercial) | -40 C to +125 C (E) | -40 C to +85 C (industrial, I) |
| Supply Voltage | 4.0 V to 5.5 V | 4.0 V to 5.5 V | 4.0 V to 5.5 V | 4.0 V to 5.5 V | 4.0 V to 5.5 V |
| Lifecycle Status | NRND | NRND | NRND | NRND | NRND |
Key Differentiators
- Extended -40 C to +125 C operating range with same silicon as the commercial-grade sibling (vs PIC16C73B-04/SS)
- Same OTP die and pinout across the entire PIC16C73B family, enabling single BOM line with grade variants (vs PIC16C73B-04I/SS)
- Lower oscillator margin cost versus the 20 MHz grade (vs PIC16C73B-20/SS)
Design Notes
Power the PIC16C73BT-04E/SS from a well-decoupled 5 V rail: place a 100 nF ceramic bypass capacitor directly across VDD (pin 20) and VSS (pin 19), within 5 mm of the IC body. Brown-out reset is enabled by configuration bits and triggers around 4.0 V; if the supply can sag below that, add a 10 uF bulk capacitor on the rail to prevent false resets. Estimated: with all peripherals off, the part draws roughly 5 mA at 5 V and 4 MHz; expect an additional 2-3 mA when the ADC and USART are active.
The PIC16C73BT-04E/SS is rated for -40 C to +125 C junction, but SSOP packages have higher thermal resistance than QFPs. Estimated: theta_JA for the 28-SSOP on a 1 oz 2-layer board is roughly 100 C/W, so 100 mW dissipation yields a 10 C junction rise. Place temperature-sensitive analog traces away from regulator inductors and avoid routing high-current outputs under the part.
Because the PIC16C73BT-04E/SS uses OTP memory, there is no second chance - a single wrong programming voltage or bad configuration-bit row bricks the device. Always (1) verify the CONFIG word with your assembler's .inc file, (2) confirm VPP stays between 12.5 V and 13.5 V during programming, and (3) apply MCLR low during power-up until Vdd settles to within 5 percent of nominal. For prototype work, substitute a PIC16F73 (Flash) so firmware can be iterated without replacing the silicon.
Keep the crystal/oscillator traces short (under 5 mm) and surround them with a ground pour to avoid coupling noise into PORTC. Place C1 and C2 (typical 22 pF) right at the OSC1/OSC2 pins. If using an external clock, drive OSC1 only and leave OSC2 floating per datasheet; routing RC6/RC7 (USART) and RC3/RC4 (I2C) away from the oscillator traces prevents cross-talk into the serial lines.
Compliance Information
RoHS and REACH compliance per Microchip product page. Not AEC-Q100 qualified; for new automotive designs use PIC18 or dsPIC families with explicit automotive certification. Lead-free (Pb-free) reflow profile per JEDEC J-STD-020.
