PIC16C74BT-20E/PT - 8-Bit 20MHz 7KB OTP MCU | Microchip
MPN: PIC16C74BT-20E/PT ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $12.5 | $12.50 |
| 10 | $11.25 | $112.50 |
| 100 | $9.95 | $995.00 |
| 500 | $8.85 | $4,425.00 |
| 1,000 | $7.75 | $7,750.00 |
PIC16C74BT-20E/PT Overview
What is a PIC16C mid-range MCU? The PIC16C74B belongs to Microchip's PIC16C mid-range family of 8-bit CMOS microcontrollers - fully-static RISC-style processors featuring a 14-bit instruction set, single-cycle execution except for branches, and a Harvard architecture separating program and data memory. The PIC16C family sits within the broader 8-bit MCU hierarchy (8-bit microcontroller -> microcontroller -> embedded computing -> semiconductor IC) and is designed for cost-sensitive embedded control applications requiring deterministic execution, low power consumption, and peripheral integration.
Key features of the PIC16C74BT-20E/PT include an integrated 8-channel, 8-bit Analog-to-Digital Converter (ADC), three timer/counter modules, a Universal Synchronous Asynchronous Receiver Transmitter (USART), a Synchronous Serial Port (SSP) supporting SPI and I2C, a Capture/Compare/PWM (CCP) module, and 33 digital I/O pins across multiple ports. The device operates from 2.5V to 6.0V and offers low-power Sleep mode with wake-up on pin change.
Architecturally, the PIC16C74B uses a 14-bit program word and 8-bit data path with a two-stage pipeline, achieving 200ns instruction cycle at 20MHz. The device is fabricated in CMOS technology with OTP EPROM program memory, making it ideal for mature, stable production designs where field reprogrammability is not required. Brown-out Reset (BOR), Power-on Reset (POR), and Watchdog Timer with its own on-chip RC oscillator provide robust system-level reliability.
Typical applications include industrial motor control, HVAC fan/blower controllers, appliance control boards, automotive body electronics (non-safety), sensor signal conditioning with on-chip ADC, and legacy embedded system upgrades where PIC16C code compatibility is required. The Extended temperature grade supports outdoor and industrial enclosure deployments.
When designing with this MCU, ensure that OTP programming is performed before final PCB conformal coating, as OTP memory cannot be re-programmed in-circuit. The 44-TQFP package requires careful PCB layout with proper ground planes to minimize noise coupling into the analog ADC inputs, and decoupling capacitors must be placed within 3mm of each VDD pin per Microchip guidance.
This page synthesizes distributor pricing, parametric drop-in alternatives, and practical design notes not consolidated in the manufacturer datasheet alone - including lifecycle status, cross-reference candidates, and TQFP-44 layout guidance compiled from Microchip application notes.
Drop-in alternatives for PIC16C74BT-20E/PT — 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 PIC16C74BT-20E/PT (same form factor and footprint) — differing in Core Architecture, Program Memory Size, Program Memory Type, Maximum Clock Frequency, RAM Size.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C74B-20I/PT
✅ Drop-In✓ In Stock
$4.62 / Unit
View Datasheet →PIC16C74BT-04I/PT
✅ Drop-In✓ In Stock
$7.1 / Unit
View Datasheet →PIC16C74BT-20/PT
✅ Drop-In✓ In Stock
$5.45 / Unit
View Datasheet →PIC16C74BT-04E/PT
✅ Drop-In✓ In Stock
$6.08 / Unit
View Datasheet →PIC16F74-I/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C74BT-20E/PT Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC16C mid-range 8-bit RISC |
| Instruction Set Width | 14 bits |
| Maximum Clock Frequency | 20 MHz |
| Instruction Cycle Time | 200 ns (at 20 MHz) |
| Program Memory Type | OTP EPROM |
| Program Memory Size | 7 KB (4K x 14) |
| RAM | 192 bytes |
| Data EEPROM | Not present (OTP family) |
| ADC | 8-channel, 8-bit |
| Supply Voltage (VDD) | 2.5 V to 6.0 V |
| Operating Temperature | -40 C to +125 C (Extended, "E") |
| Digital I/O Pins | 33 |
| Timers | 3 (Timer0, Timer1, Timer2) |
| CCP Modules | 1 (Capture/Compare/PWM) |
| Communication Peripherals | USART + SSP (SPI / I2C) |
| Package | 44-pin TQFP (10x10 mm) |
| Mounting Type | Surface Mount |
PIC16C74BT-20E/PT Pin Configuration
| Pin 1 | MCLR#/VPP — Master Clear (Reset, active low) / Programming voltage input |
| Pin 2 | RA0/AN0 — PORTA bit 0 / Analog input channel 0 |
| Pin 3 | RA1/AN1 — PORTA bit 1 / Analog input channel 1 |
| Pin 4 | RA2/AN2 — PORTA bit 2 / Analog input channel 2 |
| Pin 5 | RA3/AN3/VREF — PORTA bit 3 / Analog input channel 3 / ADC VREF+ |
| Pin 6 | RA4/T0CKI — PORTA bit 4 / Timer0 clock input |
| Pin 7 | RA5/AN4/SS# — PORTA bit 5 / Analog input 4 / SPI Slave Select |
| Pin 8 | RE0/RD#/AN5 — PORTE bit 0 / Read control / Analog input 5 |
| Pin 9 | RE1/WR#/AN6 — PORTE bit 1 / Write control / Analog input 6 |
| Pin 10 | RE2/CS#/AN7 — PORTE bit 2 / Chip Select / Analog input 7 |
| Pin 11 | VSS — Ground reference |
| Pin 12 | OSC1/CLKIN — Oscillator crystal input / External clock input |
| Pin 13 | OSC2/CLKOUT — Oscillator crystal output / Clock output |
| Pin 14 | RC0/T1OSO/T1CKI — PORTC bit 0 / Timer1 oscillator output / Timer1 clock |
| Pin 15 | RC1/T1OSI/CCP2 — PORTC bit 1 / Timer1 oscillator input / CCP2 output |
| Pin 16 | RC2/CCP1 — PORTC bit 2 / Capture/Compare/PWM1 output |
| Pin 17 | RC3/SCK/SCL — PORTC bit 3 / SPI clock / I2C clock |
| Pin 18 | RD0 — PORTD bit 0 |
| Pin 19 | RD1 — PORTD bit 1 |
| Pin 20 | RD2 — PORTD bit 2 |
| Pin 21 | RD3 — PORTD bit 3 |
| Pin 22 | RC4/SDI/SDA — PORTC bit 4 / SPI data in / I2C data |
| Pin 23 | RC5/SDO — PORTC bit 5 / SPI data out |
| Pin 24 | RC6/TX/CK — PORTC bit 6 / USART transmit / USART clock |
| Pin 25 | RC7/RX/DT — PORTC bit 7 / USART receive / USART data |
| Pin 26 | RD4 — PORTD bit 4 |
| Pin 27 | RD5 — PORTD bit 5 |
| Pin 28 | RD6 — PORTD bit 6 |
| Pin 29 | RD7 — PORTD bit 7 |
| Pin 30 | VSS — Ground reference |
| Pin 31 | VDD — Positive supply voltage |
| Pin 32 | RB0/INT — PORTB bit 0 / External interrupt |
| Pin 33 | RB1 — PORTB bit 1 |
| Pin 34 | RB2 — PORTB bit 2 |
| Pin 35 | RB3 — PORTB bit 3 |
| Pin 36 | RB4 — PORTB bit 4 |
| Pin 37 | RB5 — PORTB bit 5 |
| Pin 38 | RB6/PGC — PORTB bit 6 / In-circuit debugger clock |
| Pin 39 | RB7/PGD — PORTB bit 7 / In-circuit debugger data |
| Pin 40 | VSS — Ground reference |
| Pin 41 | VDD — Positive supply voltage |
| Pin 42 | NC — Not connected (per datasheet) |
| Pin 43 | NC — Not connected (per datasheet) |
| Pin 44 | NC — Not connected (per datasheet) |
Typical Applications
PIC16C74BT-20E/PT is suitable for 6 applications: Industrial Motor Control, HVAC Fan / Blower Controller, Appliance Control Board, Automotive Body Electronics (Non-Safety), Sensor Signal Conditioning Hub, Legacy Embedded System Sustainment.
Industrial Motor Control
The PIC16C74BT-20E/PT suits industrial motor control applications requiring deterministic real-time response and integrated analog feedback. Its 20 MHz instruction cycle (200 ns) enables sub-microsecond control loop execution for brushed DC motor velocity and torque loops. The 8-channel 8-bit ADC captures current-sense amplifiers and tachogenerator feedback simultaneously, while the CCP module generates PWM drive signals at up to 10 kHz with 10-bit resolution. The 33 I/O pins provide direct interface to H-bridge drivers, encoder inputs, and fault detection circuitry. Extended -40 C to +125 C operation handles cabinet-mounted applications. Use the PIC16C74BT-20E/PT when firmware is locked and verified; for new designs prefer PIC16F74-I/PT.
Recommended
HVAC Fan / Blower Controller
The PIC16C74BT-20E/PT integrates the I/O, ADC, PWM, and communication peripherals needed for closed-loop HVAC blower control in a single 44-TQFP package. The 8-bit ADC reads temperature sensors (NTC thermistors via resistor divider) and pressure transducers for variable-air-volume systems. The CCP module generates a PWM drive for the blower MOSFET, while the USART interfaces to the building management system (BACnet/Modbus gateway). The Extended -40 C to +125 C temperature range supports rooftop unit installations. The 192-byte RAM and 7 KB OTP memory fit typical fan-control state machines including soft-start, fault lockout, and ramp-down profiles. OTP permanence suits safety-certified HVAC designs where firmware validation is locked.
Recommended
Appliance Control Board
The PIC16C74BT-20E/PT is widely deployed in major-appliance control boards (washing machines, dishwashers, ovens) where its OTP memory, integrated peripherals, and Extended temperature range provide the right balance of cost, integration, and reliability. The 33 digital I/O pins drive relay coils, triac gates, valve solenoids, and seven-segment displays directly. The USART enables in-system diagnostics or factory calibration via an external test fixture. Brown-out Reset and Watchdog Timer maintain safe operation across AC-line brown-outs. The 7 KB OTP program memory holds complex wash-cycle or cooking profiles with multiple phase transitions. Choose this part for legacy or cost-sensitive appliance designs; new designs should evaluate PIC16F1939 for enhanced peripherals.
Recommended
Automotive Body Electronics (Non-Safety)
The PIC16C74BT-20E/PT serves in non-safety automotive body modules such as seat controllers, mirror adjusters, interior lighting, and accessory multiplexers. Its Extended -40 C to +125 C operating range handles under-dash and cabin environments. The USART supports LIN (Local Interconnect Network) slave implementations with bit-banged timing on general I/O when needed. The ADC multiplexes multiple switch-position inputs and thermistor sensors. OTP memory provides firmware immutability, an advantage for anti-tamper or anti-counterfeit applications. Note that AEC-Q100 automotive qualification is not specified for this commercial/industrial grade part; for safety-critical automotive designs, choose PIC16F74-I/PT with appropriate automotive-grade documentation or a Q-qualified equivalent.
Recommended
Sensor Signal Conditioning Hub
The PIC16C74BT-20E/PT functions as a multi-channel sensor signal conditioning and digital conversion hub in industrial instrumentation. The 8-channel 8-bit ADC digitizes strain gauge bridges, thermistors, photocells, and 4-20 mA loop receivers (via burden resistor). The SPI/I2C peripheral reads calibration data from external EEPROM or higher-resolution ADC companions. The USART outputs digital telemetry to a host controller or industrial network gateway. With Extended temperature operation, the device survives factory-floor cabinet environments. OTP memory locks calibration coefficients in firmware, eliminating the need for external non-volatile memory. This suits pressure transmitters, weigh scales, and multi-zone environmental monitors.
Recommended
Legacy Embedded System Sustainment
The PIC16C74BT-20E/PT supports long-life sustainment of legacy embedded systems where re-qualification of firmware is cost-prohibitive. Examples include industrial CNC controllers, medical instrumentation (post design freeze), and aerospace ground-support equipment. The 7 KB OTP memory holds verified firmware that has accumulated regulatory and customer approvals over decades; replacing the MCU family would trigger costly re-validation. The Extended temperature range and 44-TQFP package match existing PCB footprints, enabling drop-in replacement on field-returned boards. For these sustainment scenarios, the NRND lifecycle status means Microchip provides long-term purchase support with extended lead times, and cross-reference alternatives ensure availability during component shortages.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C74BT-20E/PT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C74B-20I/PT | PIC16C74BT-04I/PT | PIC16C74BT-20/PT | PIC16C74BT-04E/PT | PIC16F74-I/PT |
|---|---|---|---|---|---|---|
| Package | 44-TQFP (10x10 mm) | 44-TQFP (10x10 mm) - same | 44-TQFP (10x10 mm) - same | 44-TQFP (10x10 mm) - same | 44-TQFP (10x10 mm) - same | 44-TQFP (10x10 mm) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Max Clock Frequency | 20 MHz | 20 MHz | 4 MHz | 20 MHz | 4 MHz | 20 MHz |
| Program Memory Type | OTP EPROM | OTP EPROM | OTP EPROM | OTP EPROM | OTP EPROM | Flash |
| Operating Temperature | -40 C to +125 C | -40 C to +85 C | -40 C to +85 C | 0 C to +70 C | -40 C to +125 C | -40 C to +85 C |
| 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) | 7 KB (4K x 14) |
| ADC | 8-ch, 8-bit | 8-ch, 8-bit | 8-ch, 8-bit | 8-ch, 8-bit | 8-ch, 8-bit | 8-ch, 8-bit |
| Lifecycle Status | NRND | NRND | NRND | NRND | NRND | Active |
Key Differentiators
- Extended -40C to +125C temperature grade (vs PIC16C74B-20I/PT)
- Full 20 MHz speed grade versus derated family members (vs PIC16C74BT-04E/PT)
- OTP memory lock for regulatory-approved firmware (vs PIC16F74-I/PT)
Design Notes
Place decoupling capacitors (100 nF ceramic plus optional 10 uF tantalum or ceramic) within 3 mm of each VDD pin (pins 31 and 41 on the 44-TQFP package) and each VSS pin. Use a star-ground topology with separate analog (VSS) and digital (DGND) returns joined only at the MCU VSS pin. For ADC accuracy, place the analog reference bypass capacitor (100 nF) directly at the VREF+ pin with trace length under 5 mm. The exposed pad on the 44-TQFP (PT) package should be soldered to a copper pad on the PCB for thermal dissipation, even though this pin is internally connected to VSS.
The PIC16C74BT-20E/PT uses OTP (One-Time Programmable) EPROM, which CANNOT be re-programmed in-circuit. Once programmed, the device must be discarded if a firmware bug is found. Always program OTP parts on a development board or socketed adapter first, then transfer to production board. Also note the MCLR#/VPP pin requires a careful reset circuit: a 10 kohm pull-up to VDD plus a 100 nF capacitor to ground provides a clean power-on reset; do not leave MCLR# floating. The ICSP (In-Circuit Serial Programming) pins RB6/PGC and RB7/PGD must be accessible for production programming.
Estimated: at 20 MHz clock with VDD = 5.0 V and all peripherals active, the PIC16C74BT-20E/PT typical operating current is approximately 15-20 mA. Sleep mode reduces this to under 5 uA typical. Brown-out Reset (BOR) should be enabled in the configuration word to ensure safe reset on VDD brown-out; BOR threshold options include 2.5V, 4.0V, and 4.5V. The Watchdog Timer (WDT) with its own 18 ms (nominal) internal RC oscillator is independent of the system clock and continues running during Sleep to wake the MCU on overflow.
Compliance Information
RoHS/lead-free status for the PT (TQFP) suffix variant is not explicitly stated in the verified data; verify on Microchip product page before quoting. AEC-Q100 not qualified - for safety-critical automotive, choose a Q-qualified part. Conflict-minerals compliance assumed per Microchip standard policy.