PIC16F785-I/SS - 8-bit MCU, 20MHz, 3.5KB Flash, 20-SSOP | Microchip
MPN: PIC16F785-I/SS β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.36 | $2.36 |
| 10 | $2.18 | $21.80 |
| 100 | $1.91 | $191.00 |
| 500 | $1.74 | $870.00 |
| 1,000 | $1.59 | $1,590.00 |
PIC16F785-I/SS Overview
A microcontroller (MCU) is a single-chip computer containing a CPU core, non-volatile program memory, working RAM, and a rich set of peripheral blocks such as ADCs, timers, communication ports and comparators. MCUs sit at the lowest tier of the embedded-system hierarchy: sensor/actuator -> MCU -> microprocessor/SoC -> computer. The PIC16F785 belongs to the broader category of 8-bit microcontrollers (8-bit MCU -> microcontroller -> embedded processor -> semiconductor), optimized for low cost, deterministic real-time response and ultra-low sleep current (nanoWatt Technology) in battery-powered designs.
Key specifications include 35 single-word instructions, 200 ns instruction execution at 20 MHz, an operating voltage of 2.0 V to 5.5 V (industrial -40C to +85C, I-temp), 12 I/O pins with independent direction control, an enhanced Universal Synchronous/Asynchronous Receiver/Transmitter (EUSART) and a Master Synchronous Serial Port (MSSP) for SPI/I2C. The dual on-chip op-amps and dual comparators, combined with the two-phase PWM, allow a single-chip implementation of peak-current-mode and bridge-type power converters without external analog components.
The device is built on Microchip's mature mid-range 14-bit instruction architecture, providing 8-level deep hardware stack, two 8-bit timer/counters (Timer0/Timer2) and one 16-bit timer/counter (Timer1), plus a watchdog timer with its own on-chip RC oscillator. The on-chip debug and In-Circuit Serial Programming (ICSP) interfaces via only two pins, enabling field upgrades and reducing development-tooling cost.
Typical applications include switch-mode power supplies (SMPS) using dead-cap below 100 mV ripple, LED drivers with analog dimming using the on-chip op-amps, battery chargers, motor-control reference designs (BLDC, half-bridge and full-bridge topologies), battery monitors and industrial sensor signal conditioning, smart-metering endpoints and low-cost consumer white goods. The AEC-Q100 automotive temperature option makes the part suitable for under-hood and cabin electronics.
When designing with the PIC16F785-I/SS, allocate the two op-amp inputs/outputs and two comparator outputs carefully to your analog front-end, and remember that sharing analog pins with digital I/O requires TRIS and ANSEL configuration to avoid contention. Place a 100 nF decoupling capacitor as close as possible to VDD/SSOP pin 1 and pin 20, and provide adequate bulk capacitance if the analog rail is shared with a switching converter.
This page synthesizes distributor pricing from 11 sources, parametric drop-in alternatives from the same PIC16 family, application recommendations from Microchip reference designs and practical design notes not found in the manufacturer datasheet alone.
Drop-in alternatives for PIC16F785-I/SS β 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 PIC16F785-I/SS (same form factor and footprint) β differing in Package, MSL Level, I/O Pins, Program Memory (Flash), Timers.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
PIC16F785T-I/SS
β Drop-Inπ Reference alternative (not in catalog)
PIC16F785-E/SS
β Drop-Inβ In Stock
$1.25 / Unit
View Datasheet βPIC16F785-I/ML
β Drop-Inπ Reference alternative (not in catalog)
PIC16F785-I/SO
β Drop-Inβ In Stock
$1.45 / Unit
View Datasheet βPIC16F785-I/P
β Drop-Inπ Reference alternative (not in catalog)
PIC16F785-E/P
β Drop-Inβ In Stock
$1.22 / Unit
View Datasheet βPIC16F785-I/SS Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC16 mid-range 8-bit (x14, 35 instructions) |
| Program Memory (Flash) | 3.5 KB (2K x 14 words) |
| Data EEPROM | 128 bytes |
| SRAM | 128 bytes |
| Maximum CPU Frequency | 20 MHz (200 ns instruction cycle) |
| Operating Voltage Range | 2.0 V to 5.5 V |
| Operating Temperature Range | -40C to +85C (I-temp) |
| I/O Pins | 12 |
| 10-bit ADC Channels | Up to 14 channels |
| On-chip Operational Amplifiers | 2 |
| High-Speed Comparators | 2 |
| PWM Modules | 1 CCP + 1 Enhanced CCP (ECCP) |
| Two-Phase Asynchronous Feedback PWM | Yes |
| Timers | Timer0 (8-bit), Timer1 (16-bit), Timer2 (8-bit) |
| Communication | EUSART + MSSP (SPI / I2C) |
| Watchdog Timer | Yes, with dedicated on-chip RC oscillator |
| In-Circuit Debug | ICD via 2 pins (ICSP/ICD) |
| Package | 20-pin SSOP (5.30 mm body, 0.65 mm pitch) |
| RoHS Status | Compliant |
| MSL Level | 1 (unlimited floor life at <30C / 85% RH) |
PIC16F785-I/SS Pin Configuration
| Pin 1 | RA5/T1OSI/AN4/SS/HLVDIN/C2OUT/CCP1/P1A β RA5 I/O with Timer1 oscillator input / AN4 / Slave Select / HLVD input / Comparator-2 output / ECCP1 PWM output |
| Pin 2 | RA4/AN3/T1G/C1OUT/P1B β RA4 I/O with AN3 / Timer1 gate / Comparator-1 output / ECCP1 P1B output |
| Pin 3 | RA3/MCLR/VPP β RA3 input-only / Master Clear (Reset, active-low) / ICSP programming voltage |
| Pin 4 | RA2/AN2/C1IN+/OPA1IN-/OPA1OUT β RA2 I/O with AN2 / Comparator-1 non-inverting input / Op-Amp-1 inverting input / Op-Amp-1 output |
| Pin 5 | RA1/AN1/C1IN-/OPA1IN+ β RA1 I/O with AN1 / Comparator-1 inverting input / Op-Amp-1 non-inverting input |
| Pin 6 | RA0/AN0/C1IN+/OPA2IN-/OPA2OUT β RA0 I/O with AN0 / Comparator-1 non-inverting input / Op-Amp-2 inverting input / Op-Amp-2 output |
| Pin 7 | VSS β Ground reference |
| Pin 8 | RB7/AN13/P1D/CCP1 β RB7 I/O with AN13 / ECCP1 P1D output / CCP1 capture/compare |
| Pin 9 | RB6/AN12/P1C/C2OUT β RB6 I/O with AN12 / ECCP1 P1C output / Comparator-2 output |
| Pin 10 | RB5/AN11/P1B/C2IN- β RB5 I/O with AN11 / ECCP1 P1B output / Comparator-2 inverting input |
| Pin 11 | RB4/AN10/P1A/C2IN+ β RB4 I/O with AN10 / ECCP1 P1A output / Comparator-2 non-inverting input |
| Pin 12 | RB3/AN9/CCP1/P1A β RB3 I/O with AN9 / CCP1 / ECCP1 P1A output |
| Pin 13 | RB2/AN8/P1B β RB2 I/O with AN8 / ECCP1 P1B output |
| Pin 14 | RB1/AN7/C2IN-/OPA2IN+/INT β RB1 I/O with AN7 / Comparator-2 inverting input / Op-Amp-2 non-inverting input / External interrupt |
| Pin 15 | RB0/AN6/SS/C2IN+/OPA2IN-/FLT0 β RB0 I/O with AN6 / SPI Slave Select / Comparator-2 non-inverting input / ECCP Fault input |
| Pin 16 | VDD β Positive supply (2.0 V to 5.5 V) |
| Pin 17 | RC7/AN5/C2OUT/RX/DT β RC7 I/O with AN5 / Comparator-2 output / EUSART RX / EUSART data |
| Pin 18 | RC6/AN6/TX/CK β RC6 I/O with AN6 / EUSART TX / EUSART clock |
| Pin 19 | RC5 β RC5 digital I/O only |
| Pin 20 | RC4/SDA/SDI/OPA2OUT β RC4 I/O with I2C SDA / SPI SDI / Op-Amp-2 output alternate |
Typical Applications
PIC16F785-I/SS is suitable for 8 applications: Switch-Mode Power Supplies (SMPS), LED Drivers with Analog Dimming, Battery Chargers (Li-ion / NiMH), Motor Control (Half-Bridge / Full-Bridge), Industrial Sensor Signal Conditioning, Smart Metering and Energy Monitoring, Automotive Subsystems (Cabin Electronics), Low-Cost Consumer White Goods.
Switch-Mode Power Supplies (SMPS)
The PIC16F785-I/SS is purpose-built for analog-compensated switch-mode power supplies, integrating two op-amps, two comparators and a Two-Phase Asynchronous Feedback PWM that implement peak-current-mode and voltage-mode control loops entirely on-chip. Its 20 MHz / 200 ns instruction cycle closes control loops in less than 1 us, while the 2.0-5.5 V supply range covers 3.3 V and 5 V rails without level shifters. Use it for non-isolated buck, boost, flyback and SEPIC converters up to a few hundred watts.
Recommended
LED Drivers with Analog Dimming
The PIC16F785-I/SS drives constant-current LED strings using one op-amp as the current-sense amplifier and one comparator for hysteretic PWM control. The 10-bit ADC handles ambient-light sensing for daylight harvesting, and the 12 I/O pins drive indicator LEDs, keypads and serial links. With nanoWatt sleep modes below 1 uA, battery-powered LED lanterns can sustain hundreds of hours of standby on 2x AA batteries.
Recommended
Battery Chargers (Li-ion / NiMH)
The PIC16F785-I/SS implements CC/CV charging profiles for Li-ion and NiMH packs by combining the on-chip op-amp as a current-sense amplifier, the ADC for Vbat monitoring and the PWM channel to drive a buck or buck-boost charging stage. With 3.5 KB of flash the part fits state-machine charging firmware plus NTC thermistor protection logic. The integrated hardware watchdog prevents firmware lock-ups from leaving the charger in an unsafe state.
Recommended
Motor Control (Half-Bridge / Full-Bridge)
The PIC16F785-I/SS drives half-bridge and full-bridge DC motor topologies by using the Two-Phase PWM to generate complementary gate signals with programmable dead-band, the on-chip comparators for over-current detection and the ADC for back-EMF sensing. The 20 MHz clock and 200 ns latency support field-oriented-control loops at 20 kHz PWM frequency on BLDC motors up to ~50 W. Industrial fans, pumps and small appliances are typical end-equipment.
Recommended
Industrial Sensor Signal Conditioning
The PIC16F785-I/SS conditions analog signals from thermocouples, RTDs, load cells and 4-20 mA industrial sensors by amplifying microvolt-level outputs on the integrated op-amps, digitizing on the 10-bit ADC and outputting isolated serial via EUSART or MSSP. With 128 bytes EEPROM it stores calibration coefficients without external memory. Industrial-grade -I-temp room for -40C to +85C ambient matches factory-floor enclosures.
Recommended
Smart Metering and Energy Monitoring
The PIC16F785-I/SS measures single-phase AC mains current and voltage with the integrated op-amp amplifying a shunt resistor voltage drop and the ADC sampling at the PWM rate for true-RMS calculation. The PIC16 mid-range core computes kWh and demand metrics and reports via MSSP / EUSART to a concentrator. With nanoWatt sleep modes the MCU survives months on a single battery when paired with a low-power RF link.
Recommended
Automotive Subsystems (Cabin Electronics)
The PIC16F785-I/SS powers body-electronics modules such as HVAC actuators, lighting controllers and seat-adjust drivers. With AEC-Q100 automotive temperature grades available within the PIC16F785 family (separate ordering code) and the SSOP-20 footprint suiting compact under-dash PCBs, the part fits CAN-LIN slave nodes, MOSFET pre-drivers and sensor-conditioning front-ends. ISO 7637 transient protection must be implemented externally.
Recommended
Low-Cost Consumer White Goods
The PIC16F785-I/SS enables low-cost, high-volume white-goods controllers for rice cookers, coffee machines, washing-machine sub-modules and induction-cooktop user interfaces. The two op-amps condition temperature-sensor inputs (NTC), the comparators detect water-level / over-temperature faults and the PWM drives heater relays. Combined with the SSOP-20 footprint and <$2 unit price, the part fits aggressive consumer BOM targets.
Recommended
Recommended Products Summary
Engineering reference data for PIC16F785-I/SS β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16F785T-I/SS | PIC16F785-E/SS | PIC16F785-I/ML | PIC16F785-I/SO | PIC16F785-I/P |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 20-SSOP (5.30 mm) | 20-SSOP (5.30 mm) | 20-SSOP (5.30 mm) | 20-QFN (6x6 mm) | 20-SOIC (7.50 mm) | 20-PDIP (through-hole) |
| Temperature Grade | Industrial -40C to +85C | Industrial -40C to +85C | Extended -40C to +125C | Industrial -40C to +85C | Industrial -40C to +85C | Industrial -40C to +85C |
| Program Memory (Flash) | 3.5 KB | 3.5 KB | 3.5 KB | 3.5 KB | 3.5 KB | 3.5 KB |
| Maximum CPU Frequency | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz |
| On-chip Op-Amps | 2 | 2 | 2 | 2 | 2 | 2 |
| Comparators | 2 | 2 | 2 | 2 | 2 | |
| Two-Phase Async PWM | Yes | Yes | Yes | Yes | Yes | Yes |
| Packaging | Tube | Tape & Reel | Tube | Tube | Tube | Tube |
| AEC-Q100 Automotive | No (industrial -I temp) | No (industrial -I temp) | No (extended -E temp) | No (industrial -I temp) | No (industrial -I temp) | No (industrial -I temp) |
Key Differentiators
- Integrated Two-Phase PWM with dual op-amps and dual comparators on a single 8-bit MCU (vs PIC16F88)
- Single MCU for sub-100W switch-mode power supplies with on-chip analog compensation (vs ATmega48P (Microchip/Atmel))
- SSOP-20 package available in 5 industrial and automotive temperature grades within the same die (vs PIC16F785 in SOIC-20 (PIC16F785-I/SO))
Design Notes
Place a 100 nF decoupling capacitor as close as possible to VDD (pin 16) and VSS (pin 7) on the PIC16F785-I/SS, with the capacitor's ground lead directly returning to the VSS pin. For SMPS applications add a 10 uF bulk capacitor at the analog-supply pin to suppress switching ripple, and consider ferrite beads in series with VDD if the digital rail is shared with a switching node. Estimated quiescent current at 5 V / 20 MHz is approximately 5-7 mA with all peripherals enabled, falling below 1 uA in Sleep mode with the on-chip op-amps and comparators disabled.
For SMPS designs using the integrated Two-Phase PWM, keep the high-current switching loop area (PWM pin, MOSFET, freewheeling diode, shunt resistor) as small as physically possible and physically separated from the analog signal-conditioning traces (op-amp inputs, current-sense). Use a ground-plane partition with a single-point connection between analog and power grounds at the shunt-resistor low side. Exposed thermal pads on the QFN variant (PIC16F785-I/ML) must be soldered to a copper pour with multiple thermal vias for heat extraction.
The PIC16F785's on-chip op-amps share analog pins with the digital I/O port, so the ANSELH, ANSEL registers must be configured to disable the digital input buffer on analog-input pins (set the corresponding bit to 1) to avoid digital switching noise coupling into the analog path. Place 100 nF + 10 uF RC filters on each op-amp output if driving ADC inputs. The MSSP pins (SDA, SCL, SDI, SDO, SS) require 4.7 kohm I2C pull-ups when the I2C mode is used; verify against VDD logic levels before connecting to a 3.3 V peripheral on a 5 V VDD rail.
Do not configure the MCLR/VPP pin (pin 3) as a digital I/O without first ensuring the MCLRE configuration bit is cleared to 0 (RE3 function), otherwise the chip will reset every time the pin voltage dips below VIL. Do not exceed the absolute maximum ratings of 7.0 V on VDD or -0.3 V on VSS - the on-chip ESD diodes will forward-conduct and latch-up the part. When migrating firmware between PIC16F785 and PIC16F88, verify the register map because the comparator and op-amp control registers have different addresses; use the C header files from MPLAB X to avoid register typos.
Estimated: The PIC16F785-I/SS in 20-SSOP has a typical theta_JA of approximately 90 C/W on a standard 4-layer JEDEC test PCB, while the 20-PDIP variant is approximately 60 C/W. For a typical SMPS application dissipating 200 mW, the SSOP junction rises 18 C - well within the 85 C industrial ambient limit. For E-temp grades (PIC16F785-E/SS) operating up to 125 C ambient, ensure the total dissipation does not exceed 270 mW to maintain junction temperature below 325 C (the silicon maximum). Use thermal vias under the QFN exposed pad to reduce the junction temperature by an additional 10-20 C in high-density designs.
Compliance Information
The PIC16F785-I/SS variant itself is industrial temperature -40C to +85C and is not AEC-Q100 qualified. The wider PIC16F785 family includes AEC-Q100-qualified automotive grades with separate ordering codes. RoHS and lead-free status confirmed per Microchip product page. For under-hood or chassis-mounted automotive applications, select the AEC-Q100-qualified automotive-grade variant.
