ATMEGA8535L-8JUR - 8-Bit AVR MCU 8MHz 8KB Flash 44-PLCC | Microchip
MPN: ATMEGA8535L-8JUR ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.62 | $3.62 |
| 10 | $3.26 | $32.60 |
| 100 | $2.9 | $290.00 |
| 500 | $2.61 | $1,305.00 |
| 1,000 | $2.35 | $2,350.00 |
ATMEGA8535L-8JUR Overview
An AVR microcontroller is a modified-Harvard-architecture, 8-bit reduced instruction set computer (RISC) device in the broader hierarchy of microcontrollers (MCU -> embedded processor -> integrated circuit). AVR cores execute most instructions in a single clock cycle through a two-stage pipeline, giving deterministic instruction timing that is prized in real-time embedded systems. The ATmega8535 sits in the mid-range ATmega family between the smaller ATmega8 and larger ATmega64 parts, offering the classic AVR peripheral set with an expanded analog section.
Key features include up to 16 MIPS throughput at 16 MHz (8 MIPS at this part's 8 MHz ceiling for the L-grade), 130 powerful instructions most of which execute in a single cycle, 32 general-purpose working registers, and fully static operation. The 8-channel 10-bit analog-to-digital converter with internal bandgap reference supports direct sensor interfacing, while three flexible Timer/Counters with compare modes drive PWM and timing functions.
Connectivity covers a serial programmable USART, a byte-oriented Two-Wire Serial Interface (TWI, compatible with I2C), and a Serial Peripheral Interface (SPI) that doubles as the In-System Programming (ISP) download path. In-System Programmable Flash with Read-While-Write capability allows firmware updates in the end product without removal. Low-power modes (Idle, Power-down, Power-save) extend battery life in portable designs.
Typical applications include industrial control and automation nodes, motor control and HVAC systems, sensor data acquisition using the 8-channel ADC, and legacy AVR design maintenance where the PLCC-44 footprint must be preserved. The L suffix denotes a 2.7 V minimum supply enabling 3V-class battery-powered operation.
Design consideration: the L-grade 8 MHz speed limit must be respected; run the ATMEGA8535-16 variants if a 16 MHz clock is required, and ensure decoupling on both VCC/AVCC pins plus a stable analog reference for ADC accuracy.
This page synthesizes distributor availability, drop-in PLCC-44 alternatives, and practical design notes not found in a single manufacturer datasheet, with pricing as of 2026-09-19.
Drop-in alternatives for ATMEGA8535L-8JUR — 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 ATMEGA8535L-8JUR (same form factor and footprint) — differing in Package, Instructions, Core Architecture, Timers, Communication Interfaces.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ATMEGA8535L-8JU
✅ Drop-In✓ In Stock
$1.72 / Unit
View Datasheet →ATMEGA8535-16PJ
✅ Drop-In✓ In Stock
$3.4 / Unit
View Datasheet →ATMEGA8515L-8AUR
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$1.98 / Unit
View Datasheet →ATMEGA8515-16JI
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$5.44 / Unit
View Datasheet →AT89LP828-20JU
✅ Drop-In📋 Reference alternative (not in catalog)
ATMEGA8535L-8JUR Maximum Ratings & Electrical Characteristics
| Core Architecture | 8-bit AVR RISC |
| Core Size | 8-bit |
| Maximum Clock Frequency | 8 MHz |
| Program Memory Type | FLASH |
| Flash Program Memory | 8 KB (4K x 16) |
| SRAM Data Memory | 512 B |
| EEPROM | 512 B |
| ADC Resolution | 10-bit |
| ADC Channels | 8 |
| Supply Voltage Range | 2.7 V to 5.5 V (L grade) |
| Number of I/O Lines | 32 |
| Timers | 3 Timer/Counters with compare modes |
| Communication Interfaces | USART, SPI, TWI (I2C-compatible) |
| Instruction Set | 130 instructions, most single-cycle |
| Working Registers | 32 general purpose |
| MIPS | 16 MIPS at 16 MHz (8 MIPS at 8 MHz) |
| Programming Method | In-System Programmable (ISP) via SPI |
| Package | 44-PLCC (16.6 x 16.6 mm) |
| Mounting Type | Surface Mount |
| Temperature Range | Industrial |
| Package Option | GREEN, Tape & Reel (R suffix) |
ATMEGA8535L-8JUR green, tape & reel (r suffix) Pin Configuration Guide
Pin configuration for ATMEGA8535L-8JUR (green, tape & reel (r suffix) package). This digital IC includes GPIO, communication interfaces (UART, SPI, I2C), and power pins. Refer to the manufacturer datasheet for alternate pin functions and configuration options. Essential for embedded system design and PCB layout.
No detailed pinout data available for ATMEGA8535L-8JUR.
Refer to the datasheet for full pin configuration.
Typical Applications
ATMEGA8535L-8JUR is suitable for 6 applications: Industrial Control and Automation, Analog Sensor Data Acquisition, Motor Control and PWM Actuation, Battery-Powered Portable Instruments, HVAC and Building Automation Controllers, Legacy ATmega8535 System Maintenance and MRO.
Industrial Control and Automation
The ATMEGA8535L-8JUR fits industrial control nodes where deterministic single-cycle AVR instruction execution, three Timer/Counters with compare modes, and 32 GPIO lines drive relays, contactors, and status indicators. The TWI (I2C) and SPI interfaces link PLC-style I/O expansion modules, while the USART provides a rugged telemetry link to SCADA gateways. With the L-grade 2.7-5.5 V supply tolerance, the device rides through brownout conditions on loosely regulated industrial 5 V rails, and the industrial temperature rating covers enclosure-mounted electronics. Watchdog timer plus brownout detection support fail-safe recovery in unattended equipment.
Recommended
Analog Sensor Data Acquisition
The integrated 8-channel 10-bit ADC with internal bandgap reference makes this MCU a compact single-chip acquisition front end. Port A multiplexes eight sensor inputs - thermistors, potentiometers, pressure bridges - directly into the 10-bit converter, eliminating an external ADC IC and its bus overhead. Conversion results stream out over USART or SPI; a 10-bit result at 8 MHz clocks through the interrupt-driven ADC routine in microseconds. L-grade 3V operation matches ratiometric sensors powered from the same rail, so accuracy tracks VREF without precision references. PLCC-44 package simplifies through-hole-style legacy panel replacement.
Recommended
Motor Control and PWM Actuation
Three flexible Timer/Counters with compare modes generate multi-channel PWM for DC motor drives, fan speed control, and heater/actuator regulation. The 8-bit AVR core closes control loops in firmware - PI loops at kilohertz rates fit comfortably at 8 MIPS. The 10-bit ADC reads back current-sense shunts or tachometer inputs on port A, while the USART reports drive status to a host. GPIO drives gate-driver or H-bridge inputs through the 32 I/O lines. Legacy 44-PLCC industrial drives built around the ATmega8535 can be serviced with the same footprint, keeping mechanical designs untouched.
Recommended
Battery-Powered Portable Instruments
The L suffix enables operation down to roughly 2.7 V, letting this MCU run directly from three AA cells or a single lithium cell through a low-cost regulator - no boost converter needed for an 8 MHz clock. AVR Idle, Power-down, and Power-save modes cut supply current between measurement bursts; the asynchronous Timer/Counter keeps timekeeping alive in Power-save with only microamp-class drain (per datasheet power tables). The 8-channel ADC digitizes battery voltage and sensor inputs, and 512 B EEPROM stores calibration constants and logged minima/maxima through power cycles without external NVRAM.
Recommended
HVAC and Building Automation Controllers
Building controllers need robust communications plus analog sensing - exactly this part's profile. The TWI/I2C bus addresses environmental sensors and RTC chips; the USART (RS-485 via external transceiver) links to Modbus-style networks; and the 8-channel ADC samples temperature, humidity, and pressure inputs directly. Three timers generate damper-motor PWM and schedule-based outputs through the 32 GPIO. The 44-PLCC through-hole-friendly legacy footprint matches the dense multi-layer and even single-layer boards common in HVAC retrofit hardware, and industrial temperature rating tolerates rooftop equipment enclosures.
Recommended
Legacy ATmega8535 System Maintenance and MRO
For maintainers of equipment designed around the original Atmel ATmega8535 in PLCC-44, this Tape & Reel part restores production-level sourcing: identical die, register map, and ISP programming, so existing firmware binaries and AVRISP tooling remain valid. Sockets and rework of PLCC-44 are well understood in industrial repair shops, making board-level field replacement practical. The GREEN RoHS-compliant package supports compliant rework and repair in current environmental regimes. Stocking both ATMEGA8535L-8JUR and ATMEGA8535-16PJ covers supply-chain risk across speed grades.
Recommended
Recommended Products Summary
Engineering reference data for ATMEGA8535L-8JUR — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATMEGA8535L-8JU | ATMEGA8535-16PJ | ATMEGA8515L-8AUR | AT89LP828-20JU |
|---|---|---|---|---|---|
| Package | 44-PLCC (16.6 x 16.6 mm) | 44-PLCC - same | 44-PLCC - same | 44-PLCC - same | 44-PLCC - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Core / Instruction Set | AVR RISC 8-bit (130 instructions) | AVR RISC 8-bit - same | AVR RISC 8-bit - same | AVR RISC 8-bit - same | 8051 core - firmware not compatible |
| Flash Memory | 8 KB (4K x 16) | 8 KB | 8 KB | 8 KB | 8 KB |
| Max Clock Frequency | 8 MHz (L grade) | 8 MHz | 16 MHz | 8 MHz | 20 MHz |
| On-chip ADC | 8-channel 10-bit | 8-channel 10-bit | 8-channel 10-bit | None (external memory interface instead) | None |
| Supply Voltage | 2.7 V to 5.5 V (L grade) | 2.7 V to 5.5 V | 4.5 V to 5.5 V | 2.7 V to 5.5 V | 4.5 V to 5.5 V |
| Firmware Compatibility | AVR ATmega8535 binaries / ISP tooling | 100% binary compatible | Binary compatible, recompile for clock | Source compatible, no ADC drivers | Requires rewrite (8051) |
Key Differentiators
- Integrated 8-channel 10-bit ADC on port A (vs ATMEGA8515L-8AUR)
- Wide 2.7-5.5 V L-grade supply range (vs ATMEGA8535-16PJ)
- Firmware-compatible AVR ecosystem in legacy PLCC-44 (vs AT89LP828-20JU)
Design Notes
The L grade (ATMEGA8535L) permits operation down to approximately 2.7 V but caps the clock at 8 MHz; the -16 grade requires 4.5-5.5 V but allows 16 MHz. Do not run the JUR above 8 MHz - instruction timing, USART baud dividers, and ADC sample clocks all assume this ceiling. Decouple both VCC and AVCC with 100 nF ceramic capacitors placed within a few millimeters of each pin, and feed AVCC from a clean supply (RC filter or ferrite from VCC) since ADC accuracy depends directly on AVCC ripple.
PLCC-44 (J-lead) footprints must match the 16.6 x 16.6 mm body with J-leads on 1.27 mm pitch; verify the footprint against the Microchip mechanical drawing before release, because PLCC pin 1 numbering (counter-clockwise from the beveled corner index) differs from TQFP conventions and mis-mapped footprints are a classic retrofit error. Keep the RESET trace short and route it away from the SPI bus, since RESET doubles as the ISP programming strobe and glitches during in-circuit flashing can corrupt the transfer.
Use ISP via the SPI pins (MOSI, MISO, SCK, RESET) for programming - this MCU has no JTAG or debugWIRE, so on-chip debugging is unavailable and testing relies on UART printf-style tracing or an external emulator on the bus. Ensure fuses are set correctly for external crystal on XTAL1/XTAL2; the default internal RC oscillator frequency tolerance is unsuitable for UART timing. Do not exceed 8 KB of flash - leave room for the boot loader section if self-programming firmware updates are planned.
The 10-bit ADC benefits from source impedance below 10 kohm on analog inputs; add 100 nF to ground on high-impedance sensor lines to act as a charge reservoir for the ADC sample capacitor. Keep analog traces on port A away from the SPI clock and USART lines, and use the internal bandgap reference option when measuring signals that vary with supply voltage so ratiometric drift is cancelled.
Compliance Information
FindIC listing identifies the GREEN package option (lead-free, halogen-free, RoHS compliant). REACH, conflict minerals, and AEC-Q100 status should be confirmed on the Microchip product page; this is a general-purpose MCU, not an automotive-qualified part.
