ATMEGA8535L-8MUR - 8-bit AVR MCU 8KB Flash 44-VQFN | Microchip
MPN: ATMEGA8535L-8MUR β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.6 | $1.60 |
| 10 | $1.45 | $14.50 |
| 100 | $1.3 | $130.00 |
| 500 | $1.18 | $590.00 |
| 1,000 | $1.05 | $1,050.00 |
ATMEGA8535L-8MUR Overview
An AVR ATmega microcontroller is an 8-bit reduced-instruction-set (RISC) MCU that executes most of its 130 powerful instructions in a single clock cycle. In the embedded-systems hierarchy, it belongs to the ATmega family of AVR microcontrollers, which sit within Microchip's broader 8-bit MCU portfolio and typically serve as the main system controller in cost-sensitive, low-power designs.
Key features include the advanced RISC core with 32 x 8-bit general-purpose working registers, a throughput of up to 16 MIPS at 16 MHz (8 MIPS at this part's 8 MHz grade), and 32 programmable I/O lines. The L-suffix grade operates from a 2.7 V to 5.5 V supply at speeds of 0 to 8 MHz, making it suitable for both 3.3 V and 5 V systems, while the non-L ATmega8535 requires 4.5 V to 5.5 V and runs to 16 MHz.
The peripheral set covers two 8-bit and two 16-bit timers/counters with PWM, an 8-channel 10-bit ADC, a byte-oriented Two-Wire Serial Interface (I2C-compatible), an SPI serial port, a programmable serial USART, and an on-chip analog comparator. Six software-selectable power-saving modes (Idle, ADC Noise Reduction, Power-save, Power-down, Standby, and Extended Standby) let designers cut current draw dramatically in battery-operated equipment.
Typical applications include industrial control panels, sensor data acquisition with the 10-bit ADC, motor control via PWM timers, building automation, and legacy AVR system maintenance where the ATmega8535 was originally designed in.
Design-wise, use the VQFN package's exposed pad for solid ground connection, keep the analog reference (AREF) path clean when using the ADC, and remember that debug relies on the debugWIRE-compatible serial interface toolchain since this generation lacks JTAG. Flash endurance and ISP support allow field firmware updates over SPI.
This page synthesizes verified distributor pricing, same-footprint drop-in alternatives across the AVR ATmega family, and practical design notes not consolidated in the manufacturer datasheet.
Drop-in alternatives for ATMEGA8535L-8MUR 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 ATMEGA8535L-8MUR (same form factor and footprint) β differing in Package, EEPROM, SRAM, Analog Comparator, Maximum Clock Frequency.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
ATMEGA8535-16MI
β Drop-In β οΈ εζ°εΎ ιͺθ―β In Stock
$3.35 / Unit
View Datasheet βATMEGA8535-16MUR
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ATMEGA16L-8MUR
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ATMEGA32L-8MUR
β Drop-In β οΈ εζ°εΎ ιͺθ―β In Stock
$4.95 / Unit
View Datasheet βATMEGA8515L-8MUR
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ATMEGA8535L-8MUR Maximum Ratings & Electrical Characteristics
| Core | AVR 8-bit RISC |
| Core Size | 8-bit |
| Program Memory Size | 8 KB (4K x 16) FLASH |
| EEPROM Size | 512 B |
| RAM Size | 512 x 8 |
| Speed | 8 MHz |
| Supply Voltage Range | 2.7 V to 5.5 V (ATmega8535L grade) |
| ADC Channels | 8-channel, 10-bit |
| Programmable I/O Lines | 32 |
| Timers/Counters | Two 8-bit and two 16-bit |
| Communication Interfaces | USART, SPI, Two-Wire Serial Interface (I2C-compatible) |
| Analog Comparator | On-chip |
| Sleep Modes | 6 (Idle, ADC Noise Reduction, Power-save, Power-down, Standby, Extended Standby) |
| Instructions | 130 powerful instructions, most single-clock cycle |
| Throughput | Up to 16 MIPS at 16 MHz (device family) |
| Package | 44-pad VQFN/MLF, 7 x 7 mm body |
| Mounting Type | Surface Mount |
| Speed Grade Definition | 0 - 8 MHz for ATmega8535L; 0 - 16 MHz for ATmega8535 |
| Available Packages (family) | 40-pin PDIP, 44-lead TQFP, 44-lead PLCC, 44-pad QFN/MLF |
ATMEGA8535L-8MUR 40-pin pdip, 44-lead tqfp, 44-lead plcc, 44-pad qfn/mlf Pin Configuration Guide
Pin configuration for ATMEGA8535L-8MUR (40-pin pdip, 44-lead tqfp, 44-lead plcc, 44-pad qfn/mlf 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-8MUR.
Refer to the datasheet for full pin configuration.
Typical Applications
ATMEGA8535L-8MUR is suitable for 6 applications: Industrial Control Panels, Multi-Channel Sensor Data Acquisition, DC Motor Control and PWM Drives, Building Automation and HVAC Nodes, Legacy AVR System Maintenance, Battery-Powered Portable Instruments.
Industrial Control Panels
The ATMEGA8535L-8MUR fits industrial control panels because its 32 programmable I/O lines, two 8-bit and two 16-bit timers with PWM, and wide 2.7 V to 5.5 V supply tolerate noisy 5 V industrial rails and brownout conditions. The single-cycle RISC core at 8 MHz delivers roughly 8 MIPS, enough for relay sequencing, button debouncing, and status-LED logic. The VQFN 7 x 7 mm footprint keeps controller area compact, and In-System Programming over SPI allows field firmware updates without desoldering the MCU from the production board.
Recommended
Multi-Channel Sensor Data Acquisition
For sensor data acquisition, the ATMEGA8535L-8MUR provides an 8-channel 10-bit ADC that can multiplex up to eight analog sensor inputs at up to 15 kSPS-class throughput, adequate for temperature, pressure, and level sensing. Running from 2.7 V to 5.5 V, it interfaces directly with 3.3 V or 5 V sensor bridges, while AVCC and AREF pins allow a clean analog supply and selectable reference for best resolution. Results stream out over USART or SPI to a host, and the ADC Noise Reduction sleep mode lowers digital noise during conversions for improved effective bit count.
Recommended
DC Motor Control and PWM Drives
The ATMEGA8535L-8MUR suits small DC motor and actuator control using its two 8-bit timers and two 16-bit timers, which generate multiple independent PWM channels with programmable resolution and dead time via output-compare pins. The 8 MHz clock gives PWM granularity sufficient for fan, pump, and conveyor speed control, and the on-chip analog comparator supports current-limit or zero-cross detection without external op-amps. Six sleep modes let the controller idle between command cycles, cutting average system current in battery-backed industrial equipment.
Recommended
Building Automation and HVAC Nodes
In building automation, the ATMEGA8535L-8MUR's Two-Wire Serial Interface (I2C-compatible) and SPI port connect it to RTC chips, EEPROM expansion, and digital temperature sensors, while the USART links to RS-485 transceivers for networked nodes. The Power-save mode with an asynchronous timer keeps real-time clocking alive at microamp-scale current, and Power-down mode drops consumption further between scheduled sampling windows. Its 512 B EEPROM stores calibration constants and node addresses that survive power cycles, which is essential for plug-and-play field installation.
Recommended
Legacy AVR System Maintenance
The ATMEGA8535L-8MUR is a primary choice for maintaining legacy ATmega8535-based systems because it remains in active lifecycle status per distributor listings as of 2026-09-19 and is still stocked by DigiKey, Mouser, and LCSC. It is firmware-identical to the original ATmega8535L, so existing hex files load without recompilation via SPI ISP. The VQFN pad layout matches the original 44-pad MLF footprint, making it a direct reflow replacement. For boards facing end-of-life sourcing risk, qualifying the pin-compatible ATmega8535-16MI provides a second-source path.
Recommended
Battery-Powered Portable Instruments
For portable instruments, the ATMEGA8535L-8MUR combines a 2.7 V minimum supply with the ATmega8535 family's six sleep modes, letting designers run from two alkaline cells or a single Li-ion cell through a simple regulator. ADC Noise Reduction mode keeps only the ADC and clock alive during measurements, improving conversion accuracy while extending runtime; Power-down mode supports years of shelf life between use. The 8 MHz grade keeps switching losses low, and the 32 I/O lines drive displays, keypads, and sensor front ends in a single 7 x 7 mm QFN package.
Recommended
Recommended Products Summary
Engineering reference data for ATMEGA8535L-8MUR β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATMEGA8535-16MI | ATMEGA16L-8MUR | ATMEGA32L-8MUR | ATMEGA8515L-8MUR |
|---|---|---|---|---|---|
| Package | 44-VQFN (7x7) | 44-VQFN (7x7) - same | 44-VQFN (7x7) - same | 44-VQFN (7x7) - same | 44-VQFN (7x7) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Max Clock Speed | 8 MHz | 16 MHz | 8 MHz | 8 MHz | 8 MHz |
| Supply Voltage | 2.7 V - 5.5 V | 4.5 V - 5.5 V | 2.7 V - 5.5 V | 2.7 V - 5.5 V | 2.7 V - 5.5 V |
| Flash Memory | 8 KB | 8 KB | 16 KB | 32 KB | 8 KB |
| SRAM | 512 B | 512 B | 1 KB | 2 KB | 512 B |
| ADC | 8-channel, 10-bit | 8-channel, 10-bit | 8-channel, 10-bit | 8-channel, 10-bit | None |
| JTAG Debug | No | No | Yes | Yes | No |
| Firmware Compatibility | Baseline (ATmega8535L) | Fully compatible (same die) | Porting required | Porting required | Compatible only if ADC unused |
Key Differentiators
- Lowest supply voltage in the ATmega8535 family (vs ATMEGA8535-16MI)
- Cost-effective 8 KB option versus larger pin-compatibles (vs ATMEGA32L-8MUR)
- Integrated 8-channel ADC absent from closest sibling (vs ATMEGA8515L-8MUR)
Design Notes
Decouple VCC and AVCC separately: place a 100 nF ceramic capacitor directly across each VCC pad to the ground return and a second 100 nF plus optional 10 uF on AVCC. AVCC powers the ADC, so tie it to VCC through a low-pass RC (e.g., 10 ohm + 100 nF) when switching loads share the 5 V rail; this suppresses digital noise from the PWM timers reaching the 10-bit converter. Keep AREF decoupled with 100 nF and never drive AREF externally while the internal reference is selected, per the ATmega8535 datasheet analog section.
The 44-pad QFN/MLF lands on the PCB center pad array; connect the die-attached pad (if used as ground) to the ground plane with a 4x4 via array to improve thermal and ground integrity. Use via-in-pad or fanout dogbones for the perimeter pads with 0.25-0.3 mm via stubs for rework access. Keep the RESET trace short and pull it up with 10 kohm for reliable ISP programming, and route XTAL1/XTAL2 as short as possible with the crystal's load capacitors placed within 2 mm of the pads.
Respect the speed-versus-voltage derating: the L grade supports 0 to 8 MHz across 2.7 V to 5.5 V, but if you substitute the ATMEGA8535-16MI, the supply must be 4.5 V to 5.5 V or the device may misbehave. This generation has no JTAG, so plan debug around ISP and serial output before layout freeze. Also note that brown-out detection settings and fuse bits differ between ATmega families; re-verify fuse configuration (clock source, BOD level, SPIEN) when porting firmware to ATmega16/32 pin-compatibles.
Compliance Information
Compliance statuses were not stated in the provided web data; confirm on the Microchip product page or distributor environmental data before procurement.
