PIC16LC73BT-04I/SS - 8-Bit PIC MCU, 7KB OTP, 4MHz, 28-SSOP | Microchip
MPN: PIC16LC73BT-04I/SS ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $7.2 | $7.20 |
| 10 | $6.5 | $65.00 |
| 100 | $5.8 | $580.00 |
| 500 | $5.1 | $2,550.00 |
| 1,000 | $4.55 | $4,550.00 |
PIC16LC73BT-04I/SS Overview
Background Knowledge: A microcontroller (MCU) is a single-chip computer that integrates a CPU core, non-volatile program memory, working RAM, and peripheral interfaces such as timers, capture/compare/PWM blocks, ADC converters, and serial ports. The PIC16CXX mid-range core used by the PIC16LC73BT belongs to the broader taxonomy of 8-bit microcontrollers -> microcontrollers -> integrated circuits -> semiconductors. Microcontrollers are the heart of embedded systems, replacing discrete logic by executing firmware that controls sensor reading, actuator driving, communication, and human-machine interfaces.
Key features include 22 digital I/O lines, a hardware USART, MSSP (SPI/I2C) peripheral, three timers (Timer0, Timer1, Timer2), a 5-channel 8-bit ADC, dual analog comparators, and an internal watchdog timer. The 04 MHz clock speed suffix designates the maximum oscillator frequency, while the LC prefix indicates the low-voltage/low-power core variant suitable for 3.3 V and 5 V rails. The /SS suffix denotes the 28-SSOP package.
Technical depth: The PIC16LC73BT uses a Harvard architecture with a separate 14-bit program word and 8-bit data path, an 8-level deep hardware stack, and 35 single-cycle instructions. The CMOS process delivers low quiescent current suitable for battery-backed applications, while the OTP program memory allows rapid prototyping without mask charges. The LC core variant draws less than 2 mA at 5 V / 4 MHz typical and supports operation down to 2.5 V, allowing portable or 3.3 V-only designs.
Typical applications include industrial automation controllers, consumer appliance control boards, sensor signal conditioning front-ends, low-cost user-interface panels, and battery-powered data loggers. The PIC16LC73BT was also extended into higher-volume products such as the PIC16F73A flash-based migration path, but the OTP/B variant remains attractive for cost-sensitive production runs.
Design consideration: OTP parts cannot be reprogrammed in-circuit, so firmware must be fully validated before programming. For field-upgradable firmware, select the PIC16F73A/SS flash variant instead; both share the same 28-SSOP pinout and pin-to-pin compatible.
This page synthesizes distributor pricing, drop-in compatible variants, and engineering comparison context not found in the manufacturer datasheet alone.
Drop-in alternatives for PIC16LC73BT-04I/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 PIC16LC73BT-04I/SS (same form factor and footprint) — differing in Package, Program Memory Size, Operating Temperature, RAM Size, RoHS Status.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16LC73B-04I/SS
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16LC73BT-04/SO
✅ Drop-In✓ In Stock
$7.1 / Unit
View Datasheet →PIC16LC73AT-04I/SO
✅ Drop-In✓ In Stock
$4.61 / Unit
View Datasheet →PIC16LC73BT-04I/SO
✅ Drop-In✓ In Stock
$4.68 / Unit
View Datasheet →PIC16LC72-04I/SS
✅ Drop-In✓ In Stock
$2.72 / Unit
View Datasheet →PIC16LC717-I/SO
✅ Drop-In✓ In Stock
$2.85 / Unit
View Datasheet →PIC16LC711T-04E/SS
✅ Drop-In✓ In Stock
$4.95 / Unit
View Datasheet →PIC16LC73BT-04I/SS Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC16CXX mid-range 8-bit |
| Maximum Clock Speed | 4 MHz |
| Program Memory Type | OTP (One-Time Programmable) |
| Program Memory Size | 7 KB (4K x 14 words) |
| Data RAM | 192 bytes |
| Data EEPROM | Not present (OTP part) |
| Supply Voltage Range | 2.5 V to 5.5 V |
| Digital I/O Pins | 22 |
| Operating Temperature | -40 C to +85 C (Industrial) |
| Package | 28-SSOP (5.30 mm body, 0.65 mm pitch) |
| Mounting Type | Surface Mount |
| ADC | 8-bit, 5 channels |
| Timers | Timer0 (8-bit), Timer1 (16-bit), Timer2 (8-bit) |
| Serial Peripherals | USART (SCI), MSSP (SPI / I2C) |
| Analog Comparators | 2 |
| Watchdog Timer | Yes (internal, software-enabled) |
| Instruction Set | 35 single-cycle instructions |
| Hardware Stack Depth | 8 levels |
| MSL Level | 1 (unlimited floor life) |
| RoHS Status | Compliant |
PIC16LC73BT-04I/SS Pin Configuration
| Pin 1 | MCLR/VPP — Master Clear (reset) input / programming voltage input |
| 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 channel 3 / ADC voltage reference |
| Pin 6 | RA4/T0CKI — Digital I/O / Timer0 clock input |
| Pin 7 | RA5/AN4/SS — Digital I/O / analog input channel 4 / SPI slave select |
| Pin 8 | OSC1/CLKIN — Oscillator crystal input / external clock input |
| Pin 9 | OSC2/CLKOUT — Oscillator crystal output / clock output |
| Pin 10 | RC0/T1OSO/T1CKI — Digital I/O / Timer1 oscillator output / Timer1 clock input |
| Pin 11 | RC1/T1OSI/CCP2 — Digital I/O / Timer1 oscillator input / Capture-Compare-PWM 2 |
| 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 — Digital I/O / USART asynchronous transmit |
| Pin 17 | RC7/RX — Digital I/O / USART asynchronous receive |
| Pin 18 | VSS — Ground reference |
| Pin 19 | VDD — Positive supply voltage (2.5 V to 5.5 V) |
| Pin 20 | RB0/INT — Digital I/O / external interrupt input |
| Pin 21 | RB1 — Digital I/O |
| Pin 22 | RB2 — Digital I/O |
| Pin 23 | RB3 — Digital I/O |
| 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 | NC — Not connected (per datasheet, pin reserved for future use) |
Typical Applications
PIC16LC73BT-04I/SS is suitable for 6 applications: Industrial Automation Controller, Consumer Appliance Control Board, Sensor Signal Conditioning Front-End, Battery-Powered Data Logger, Low-Cost HMI / User Interface Panel, Automotive Aftermarket Accessory Module.
Industrial Automation Controller
The PIC16LC73BT-04I/SS fits industrial automation controllers through its 22 digital I/O lines, three timers, hardware USART, and MSSP SPI/I2C peripheral that can interface to digital sensors, motor driver ICs, and HMI displays. The 2.5 V to 5.5 V supply range and -40 °C to +85 °C industrial temperature grade support factory-floor operating conditions without additional regulation or thermal management. Its 5-channel 8-bit ADC reads analog sensors such as temperature, pressure, and potentiometer position with sufficient resolution for setpoint control loops. Unlike higher-tier ARM Cortex MCUs it offers a simpler development path with MPLAB-X and free Hi-Tech C compiler for rapid firmware iteration in PLCs and machine controllers.
Recommended
Consumer Appliance Control Board
The PIC16LC73BT-04I/SS suits consumer appliance control boards because the 4 MHz mid-range core delivers enough MIPS to run state-machine firmware for washers, microwave ovens, and HVAC controls while keeping unit cost low for high-volume SKUs. Its 7 KB OTP memory fits typical appliance firmware (UI state machine, sensor polling, drive signals, safety interlocks) with room to spare. The 22 I/O pins directly drive LED indicators, seven-segment displays, keypads, and triac-fired relays without external multiplexers. Compared to flash PIC16F1xxx alternatives the OTP variant saves USD 0.20-0.50 per unit at 100K volume - material in cost-sensitive appliances where firmware is locked at production.
Recommended
Sensor Signal Conditioning Front-End
The PIC16LC73BT-04I/SS acts as a sensor signal conditioning front-end by combining its 5-channel 8-bit ADC with two analog comparators and MSSP I2C bus to read sensors and forward digital readings to a host MCU. The PIC16C73B 8-bit core is more than adequate to filter, average, and threshold-detect analog inputs before transmitting compact data packets over I2C. The 2.5 V minimum supply allows operation directly from a 2x AA battery stack with no boost converter, while the industrial -40 °C to +85 °C grade supports outdoor sensor pods. Unlike higher-pin-count PIC18 parts, the 28-SSOP keeps the BOM small for distributed sensor networks.
Recommended
Battery-Powered Data Logger
The PIC16LC73BT-04I/SS fits battery-powered data loggers through its LC low-voltage core drawing less than 2 mA at 4 MHz / 5 V typical, deep sleep modes below 1 µA, and 2.5 V to 5.5 V supply supporting 2x AA or 1x Li-coin cells directly. The 192-byte RAM is sufficient to buffer time-stamped samples before writing to an external I2C EEPROM such as 24LC256. The 4 MHz clock and 35-instruction PIC16CXX core provide the throughput for sampling at 1-10 Hz while spending most cycles in sleep. Versus flash PIC16F73A, the OTP variant saves cost and removes reprogrammability concerns for sealed logger units.
Recommended
Low-Cost HMI / User Interface Panel
The PIC16LC73BT-04I/SS drives low-cost HMI panels by combining 22 I/O lines for up to 4x4 matrix keypads and up to 7-segment LED displays, plus an MSSP peripheral for SPI-driven LCD modules. The PIC16C73B's 7 KB OTP memory comfortably fits keypad scan, debounce, display multiplexing, and menu state-machine firmware. At 4 MHz the MCU can refresh a 4-digit 7-segment display at 100+ Hz with simultaneous keypad scanning without flicker. Compared to PIC18 or ARM alternatives, this part keeps the HMI module under USD 5 BOM while still offering a USART for host communication in vending and ticketing machines.
Recommended
Automotive Aftermarket Accessory Module
The PIC16LC73BT-04I/SS fits aftermarket automotive accessory modules such as alarm systems, keyless-entry controllers, lighting controllers, and OBD-II readers where its -40 °C to +85 °C industrial temperature grade covers cabin installations. The 5 V supply rail can be derived from the 12 V automotive bus via a simple linear regulator; the MSSP SPI bus interfaces to CAN transceivers like MCP2515 for OBD-II dongles. Note: this is the industrial-grade part, not AEC-Q100 qualified; for under-hood or safety-critical automotive ECUs, choose the AEC-Q100 qualified PIC16 family member instead. The 7 KB OTP and 192-byte RAM are sufficient for fixed-function automotive accessories with locked firmware.
Recommended
Recommended Products Summary
Engineering reference data for PIC16LC73BT-04I/SS — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16LC73B-04I/SS | PIC16LC73BT-04/SO | PIC16LC73AT-04I/SO | PIC16LC72-04I/SS | PIC16LC717-I/SO |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-SSOP | 28-SSOP - same | 28-SOIC - same pinout | 28-SOIC - same pinout | 28-SSOP - same | 28-SOIC - same pinout |
| Program Memory | 7 KB OTP | 7 KB OTP | 7 KB OTP | 7 KB OTP (PIC16C73A predecessor) | 2 KB OTP (reduced) | 3 KB OTP |
| RAM | 192 bytes | 192 bytes | 192 bytes | 192 bytes | 128 bytes | 256 bytes |
| Max Clock Speed | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 20 MHz (faster) |
| ADC | 8-bit, 5 channels | 8-bit, 5 channels | 8-bit, 5 channels | 8-bit, 5 channels | 8-bit, 5 channels | 8-bit, 8 channels (more) |
| USART | Yes (SCI) | Yes (SCI) | Yes (SCI) | Yes (SCI) | No (not present) | Yes (SCI) |
| Operating Temperature | -40 C to +85 C (Industrial) | -40 C to +85 C (Industrial) | 0 C to +70 C (Commercial) | -40 C to +85 C (Industrial) | -40 C to +85 C (Industrial) | -40 C to +85 C (Industrial) |
Key Differentiators
- Low-voltage LC core with sub-2 mA active current (vs PIC16C73B-04I/SS)
- Industrial temperature grade available as 'I' suffix (vs PIC16LC73BT-04/SO)
- Same 28-SSOP pinout as PIC16C73A predecessor (vs PIC16LC73AT-04I/SO)
Design Notes
The PIC16LC73BT-04I/SS draws under 2 mA typical at 5 V / 4 MHz active, and below 1 µA in sleep mode per Microchip datasheet 30286A. Decouple VDD with a 100 nF ceramic cap placed within 5 mm of the VDD pin and a 10 µF bulk cap on the supply rail. For battery designs, the LC core draws significantly less than the standard C core variant, so verify your code paths maximize sleep duration to extend battery life.
Route the ICSP clock pin (PGC6) and ICSP data pin (PGD7) away from switching power and high-current traces; route the OSC1/OSC2 traces short and symmetric to avoid clock distortion. Place the MCLR pull-up (typically 10 kΩ) close to the MCLR pin and provide a decoupling cap on VCT. The 28-SSOP 0.65 mm pitch requires careful PCB manufacturing tolerance; use ENIG or HASL with proper solder paste stencil apertures per IPC-7525.
Critical: OTP program memory cannot be erased or rewritten after programming, so validate firmware thoroughly on a flash equivalent (PIC16F73A-I/SS) or emulator before committing to OTP programming. Do not exceed 5.5 V on VDD - the LC core has no internal clamp for over-voltage. The MCLR pin must not be left floating; always use the 10 kΩ pull-up. Brown-out reset must be enabled in the configuration fuses for industrial robustness.
Compliance Information
RoHS compliant per Microchip product page material declaration. Industrial temperature grade -40C to +85C; not AEC-Q100 qualified - for AEC-Q100 automotive applications, choose a PIC16 family member with Q100 qualification. Halogen-free status: ask Microchip for confirmation. Conflict-minerals statement available from Microchip.
