PIC12LF1840-I/SN - 8-bit 32MHz XLP MCU, 7KB Flash, 8-SOIC | Microchip
MPN: PIC12LF1840-I/SN ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.85 | $1.85 |
| 10 | $1.65 | $16.50 |
| 100 | $1.42 | $142.00 |
| 500 | $1.2 | $600.00 |
| 1,000 | $1.05 | $1,050.00 |
PIC12LF1840-I/SN Overview
An 8-bit microcontroller is a small computing-on-a-chip device that executes instructions on 8-bit data words; it sits within the broader taxonomy of microcontroller -> embedded controller -> semiconductor. PIC® microcontrollers use a RISC-style Harvard architecture with separate program and data buses, which enables deterministic instruction timing - most instructions execute in one instruction cycle, simplifying real-time firmware design compared with accumulator-based CISC cores.
Key features of the PIC12LF1840-I/SN include 7 KB Flash, 256 B SRAM, 256 B EEPROM, six I/O pins, four 10-bit ADC channels, two 8-bit timers plus one 16-bit timer, enhanced PWM/CCP/ECCP modules, two comparators, an EUSART, an MSSP (SPI/I²C), an on-chip 32 MHz internal oscillator, and 49 instruction opcodes with a 16-level hardware stack. Per the datasheet, XLP sleep currents are in the low-nanoampere range while the active core draws only a few hundred microampere per MHz.
Typical applications include battery-powered sensor nodes, remote controls, low-end wearable accessories, energy-harvesting controllers, IoT edge nodes, simple LED driver sequencers, and consumer white-goods user-interface boards. The wide 1.8–3.6 V supply window makes it well suited to single-cell Li-ion or two-alkaline-cell topologies.
When designing, choose the internal 32 MHz oscillator to minimize external components and use the LFDS regulator for deep sleep; configure unused I/O as outputs to avoid current leakage, and read errata notes for rev-A silicon peculiarities such as ADC gain-offset behavior in extreme temperatures.
Drop-in alternatives for PIC12LF1840-I/SN — 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 PIC12LF1840-I/SN (same form factor and footprint) — differing in ADC, MSL Level, Package, I/O Pins, Core Architecture.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC12LF1840-E/SN
✅ Drop-In✓ In Stock
$0.85 / Unit
View Datasheet →PIC12LF1840T-I/SN
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$0.58 / Unit
View Datasheet →PIC12F1840-I/SN
✅ Drop-In✓ In Stock
$0.82 / Unit
View Datasheet →PIC12F1840T-I/SN
✅ Drop-In ⚠️ 参数待验证📋 Reference alternative (not in catalog)
PIC12LF1822-I/SN
✅ Drop-In📋 Reference alternative (not in catalog)
PIC12LF1572-I/SN
✅ Drop-In📋 Reference alternative (not in catalog)
PIC12LF1840-I/SN Maximum Ratings & Electrical Characteristics
| Architecture | PIC enhanced mid-range 8-bit RISC |
| Instruction Set | 49 instructions, 16-level hardware stack |
| Core Frequency (max) | 32 MHz (8 MIPS) |
| Program Memory (Flash) | 7 KB (4K x 14) |
| SRAM | 256 B |
| EEPROM | 256 B |
| Supply Voltage Range | 1.8 V to 3.6 V (LF variant) |
| I/O Pins | 6 |
| ADC | 10-bit, 4 channels |
| Timers | 2x 8-bit, 1x 16-bit |
| PWM / CCP | ECCP + 2 CCP, 10-bit PWM |
| Communication | EUSART (LIN-capable), MSSP (SPI / I²C) |
| Comparators | 2 |
| Internal Oscillator | 31 kHz LF + 32 MHz HF, ±1% calibrated |
| XLP Sleep Current | nanoWatt range (low nA) |
| Operating Temperature | -40 °C to +85 °C (industrial, 'I') |
| Package | 8-pin SOIC (SN, 3.90 mm body) |
| Mounting Type | Surface Mount |
| MSL Level | 1 (unlimited floor life per JEDEC J-STD-020) |
| RoHS Status | Compliant |
PIC12LF1840-I/SN Pin Configuration
| Pin 1 | RA5 — Bidirectional I/O; analog input channel 4 |
| Pin 2 | RA0 — Bidirectional I/O; analog input channel 0; ICSPDAT |
| Pin 3 | RA1 — Bidirectional I/O; analog input channel 1; ICSPCLK |
| Pin 4 | RA2 — Bidirectional I/O; analog input channel 2; comparator output |
| Pin 5 | RA3/MCLR/VPP — Bidirectional I/O / master clear reset (configurable weak pull-up) / programming voltage |
| Pin 6 | RA4 — Bidirectional I/O; analog input channel 3; T0CKI clock input; comparator input |
| Pin 7 | VDD — Positive supply voltage (1.8 V to 3.6 V) |
| Pin 8 | VSS — Ground reference |
Typical Applications
PIC12LF1840-I/SN is suitable for 7 applications: Battery-Powered IoT Sensor Node, Remote Control / IR Transmitter, Wearable Fitness / Health Band Controller, Industrial Sensor Transmitter, Smart Home / Building Automation End Node, Automotive Interior Accessory Controller, Consumer White Goods User Interface.
Battery-Powered IoT Sensor Node
The PIC12LF1840-I/SN's XLP nanoWatt sleep current and 1.8 V operation make it ideal for coin-cell IoT sensor nodes that spend 99 % of the time asleep. Placed at the heart of a wireless sensor tag with an MSSP-controlled I²C temperature/humidity sensor and an EUSART-driven sub-GHz radio, the device wakes briefly to digitise the sensor, transmits a burst, and returns to deep sleep - drawing single-digit microampere average current. The 32 MHz core is fast enough to run simple on-device calibration routines between transmissions. Its 7 KB Flash accommodates application firmware plus a small RTOS or state machine, while 256 B of EEPROM stores calibration constants across battery replacements. Designers should configure all unused I/O as outputs low to eliminate floating-pin leakage paths in the sub-3 V coin-cell envelope.
Recommended
Remote Control / IR Transmitter
The PIC12LF1840-I/SN is well suited to infrared remote controls thanks to its internal 32 MHz oscillator (no crystal required), 6 I/O pins, and EUSART-driven PWM/CCP that generates precise 38 kHz / 56 kHz carrier waveforms with no external timing components. Connected to a few push-buttons, an IR LED driver transistor, and a CR2032 coin cell, the device runs for years on standby thanks to its nanoWatt sleep mode. Its on-chip EUSART plus timers allow NEC, RC5 or SIRC protocol stacks to be implemented in 7 KB of Flash with room left for custom button mappings. Industrial temperature range plus the LF low-voltage supply ensure stable performance down to the battery's end-of-life voltage around 2.0 V, maximising usable cell capacity.
Recommended
Wearable Fitness / Health Band Controller
The PIC12LF1840-I/SN powers entry-level wearable bands by combining a 10-bit ADC for heart-rate / motion sensing, an EUSART to drive a Bluetooth Low Energy module, and XLP sleep currents that extend a 100 mAh Li-Po battery into weeks of runtime. Housed in a small SOIC-8 footprint, the device fits alongside the BLE SoC on a wristband PCB while its 1.8-3.6 V supply operates directly from the Li-Po charger output. The 10-bit PWM drives vibration motor alerts; 256 B of EEPROM retains step counts and last-used profile through battery swaps; and the calibrated 32 MHz internal oscillator avoids external crystals, reducing BOM cost and PCB area. Use the LFDS regulator and configure the deep-sleep wake-up source to a pin-change interrupt for lowest quiescent draw.
Recommended
Industrial Sensor Transmitter
In industrial 4-20 mA loop or low-voltage bus transmitters, the PIC12LF1840-I/SN digitises a bridge sensor via its 10-bit ADC, applies linearisation in firmware, and drives an EUSART HART or RS-485 output. The -40 to +85 °C industrial temperature range handles factory-floor thermals; the 1.8 V operation suits loop-powered designs with an internal shunt regulator. The 7 KB Flash stores calibration tables and Modbus or HART command interpreters, while the on-chip ECCP PWM can generate a 4-20 mA loop-current reference using a single external op-amp. Pair the PIC with a small TVS protection diode to meet IEC 61000-4-2 ESD on the field-side pins; the SOIC-8 footprint is compatible with hand-rework for prototype retrofitting in legacy 8-pin sensor sockets.
Recommended
Smart Home / Building Automation End Node
The PIC12LF1840-I/SN serves as a low-cost end node in smart-home networks - driving relays, reading temperature set-points, and communicating via EUSART-controlled RS-485 or sub-GHz radios. Its MSSP supports SPI sensors and I²C EEPROM storage for configuration backup. Power is supplied from a 3.3 V LDO or directly from two AA cells, taking advantage of the 1.8-3.6 V LF supply range. The PIC's 16-bit timer captures time-of-day events, and the comparators monitor battery voltage without waking the core. The 7 KB Flash accommodates small Zigbee or LoRaWAN MAC stacks; the 8-pin SOIC package keeps the node footprint below 1 cm², ideal for behind-wall mounting boxes. The device's nanoWatt sleep supports battery-powered window-sensor or doorbell deployments lasting several years.
Recommended
Automotive Interior Accessory Controller
Although not AEC-Q100 qualified by default, the PIC12LF1840-I/SN is widely used in non-safety automotive interior accessories such as ambient lighting, USB chargers, and door-moduled keypads. Its industrial temperature range handles cabin thermal swings; its PWM/ECCP drives LED strings or small DC fans; and the MSSP communicates with body-control modules via LIN-capable EUSART. The 1.8-3.6 V supply operates from the 12 V battery after a small LDO; the 7 KB Flash stores custom lighting sequences, while 256 B of EEPROM retains user preferences across battery disconnects. Pair it with an external CAN/LIN transceiver for body-network nodes; its SOIC-8 package simplifies mechanical mounting and through-hole rework on service-bench fixtures.
Recommended
Consumer White Goods User Interface
The PIC12LF1840-I/SN powers the user-interface boards of white goods such as coffee machines, microwaves, dishwashers, and washing machines. The 10-bit ADC reads rotary encoders and temperature probes, the PWM drives beepers or triac-based heater elements, and the EUSART/MSSP talks to main control boards over UART or I²C. The SOIC-8 footprint fits behind a 7-segment display PCB; the LF 1.8 V supply operates from a small switching supply or capacitive dropper. The 7 KB Flash supports multi-stage cooking programs with EEPROM-stored favourite settings, while XLP sleep keeps standby power below 0.5 W to comply with energy-efficiency regulations. The calibrated 32 MHz internal oscillator eliminates external crystals and reduces EMI.
Recommended
Recommended Products Summary
Engineering reference data for PIC12LF1840-I/SN — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC12LF1840-E/SN | PIC12F1840-I/SN | PIC12LF1822-I/SN | PIC12LF1572-I/SN |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 8-SOIC (SN, 3.90 mm) | 8-SOIC (SN, 3.90 mm) - same | 8-SOIC (SN, 3.90 mm) - same | 8-SOIC (SN, 3.90 mm) - same | 8-SOIC (SN, 3.90 mm) - same |
| Flash Memory | 7 KB | 7 KB | 7 KB | 3.5 KB (-50 %) | 3.5 KB (-50 %) |
| Supply Voltage Range | 1.8 V to 3.6 V | 1.8 V to 3.6 V | 2.3 V to 5.5 V (mismatched) | 1.8 V to 3.6 V | 1.8 V to 3.6 V |
| Core Frequency (max) | 32 MHz | 32 MHz | 32 MHz | 32 MHz | 32 MHz |
| I/O Pins | 6 | 6 | 6 | 6 | 6 |
| ADC | 10-bit, 4 ch | 10-bit, 4 ch | 10-bit, 4 ch | 10-bit, 4 ch | 10-bit, 4 ch |
| EUSART / MSSP | Yes / Yes | Yes / Yes | Yes / Yes | Yes / Yes | No / Yes (16-bit PWM) |
| Temperature Range | -40 to +85 °C (industrial) | -40 to +125 °C (extended) | -40 to +85 °C (industrial) | -40 to +85 °C (industrial) | -40 to +85 °C (industrial) |
| EEPROM | 256 B | 256 B | 256 B | 256 B | 256 B |
Key Differentiators
- Wider temperature envelope (extended -40 to +125 °C) (vs PIC12LF1840-I/SN (industrial -40 to +85 °C))
- Doubled Flash for firmware headroom (vs PIC12LF1822-I/SN (3.5 KB Flash))
- Low-voltage 1.8 V operation including coin-cell rails (vs PIC12F1840-I/SN (2.3 V min))
- Rich peripheral set in 8-pin SOIC (vs PIC12LF1572-I/SN)
Design Notes
Configure unused I/O pins as outputs driven low to avoid floating-input leakage currents that can reach microampere levels on sub-3 V coin-cell rails. Use the LFDS low-power sleep regulator and select the deep-sleep mode (DSS = 11) to drop quiescent current to single-digit nanoampere range. According to the Microchip datasheet, current consumption in deep sleep is dominated by leakage from I/O and the WDT; disabling the WDT when not needed saves additional nanoampere.
Pin 5 is a multi-function RA3/MCLR/VPP pin; the configuration word MCLRE must be cleared to disable the master-clear reset if RA3 is needed as a regular I/O. Forgetting this keeps the weak pull-up active and can pull high the I/O line, causing unexpected current draw. Also confirm the WDT and code-protection configuration bits match your firmware - locking out debug access is a common prototyping mistake.
Place a 100 nF decoupling capacitor as close as possible to the VDD pin (pin 7) to suppress switching noise from the internal oscillator; add a bulk 10 µF tantalum or ceramic capacitor near the IC for high-current transient events such as radio-module transmissions. Keep the ICSP pins (RA0/RA1, RA3) on accessible PCB test points for in-circuit programming without removing the device from the board.
At 32 MHz, the PIC12LF1840-I/SN draws only a few milliampere from a 3.3 V supply, dissipating under 15 mW - well within the SOIC-8 thermal envelope. No thermal heatsinking is required for normal operation, and the theta_JA of approximately 100-150 °C/W (per Microchip package thermal data) keeps the junction rise below 2 °C even in enclosed industrial housings. Designers do not need to perform thermal analysis for typical low-voltage MCU designs.
When driving an external radio module via EUSART or SPI, add a 33 Ω series resistor close to the PIC output pin to dampen ringing on long PCB traces. The 32 MHz internal oscillator is factory-calibrated to ±1 % but has temperature drift; use the FOSC<FREQ> calibration routine if your application needs accurate UART baud rates over -40 to +85 °C. For sub-1 % timing accuracy, source the system clock from an external crystal or the FOSC = 16 MHz HFINTOSC tuning routine.
Compliance Information
RoHS compliant per Microchip product page; lead-free SOIC-8 packaging; standard industrial temperature -40 to +85 °C only - for AEC-Q100 qualified automotive variants consult Microchip automotive product catalogue.
