ATMEGA8535-16MU - 8KB AVR MCU 16MHz 44-VQFN | Microchip
MPN: ATMEGA8535-16MU ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $5.42 | $5.42 |
| 10 | $4.88 | $48.80 |
| 100 | $4.35 | $435.00 |
| 500 | $3.91 | $1,955.00 |
| 1,000 | $3.52 | $3,520.00 |
ATMEGA8535-16MU Overview
An 8-bit AVR microcontroller is a single-chip computer that integrates a RISC processor core, program Flash, data SRAM, EEPROM, and peripherals such as timers, USART, and ADC on one die. Within the semiconductor hierarchy it sits under microcontroller unit (MCU) -> embedded processor -> integrated circuit, and it belongs to the AVR ATmega family of flash-based MCUs used across embedded and industrial control systems.
Key features include the advanced AVR RISC architecture with 130 powerful instructions, most executing in a single clock cycle, which yields the 1 MIPS/MHz throughput rating. The 8 KB Flash supports In-System Programming with Read-While-Write capability, enabling field firmware updates. Peripheral set covers three flexible Timer/Counters with compare modes, a programmable USART, a byte-oriented Two-wire Serial Interface (I2C-compatible TWI), and the 8-channel 10-bit A/D converter.
Technically, the -16 speed grade operates from a 4.5 V to 5.5 V supply, with 32 general purpose I/O lines and 32 general purpose working registers all directly connected to the ALU, allowing single-cycle access that eliminates arithmetic bottlenecks typical of accumulator-based 8-bit architectures. Internal and external interrupt sources support responsive real-time control.
Typical applications include industrial automation and motor control nodes, sensor acquisition systems leveraging the 8-channel 10-bit ADC, and legacy embedded products requiring AVR ATmega8535 compatibility. Its 5 V operation suits noisy industrial environments where 3.3 V parts are less robust.
Design consideration: respect the 4.5-5.5 V operating window; the part is not rated for 3.3 V at the 16 MHz speed grade, so lower-voltage designs should select an L-suffix variant instead.
This page synthesizes verified distributor data, drop-in alternatives, and practical design notes beyond the manufacturer datasheet.
Drop-in alternatives for ATMEGA8535-16MU — 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 ATMEGA8535-16MU (same form factor and footprint) — differing in Package, Throughput, ADC, EEPROM, SRAM.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ATMEGA8535-16MI
✅ Drop-In✓ In Stock
$3.35 / Unit
View Datasheet →ATMEGA8535-16MUR
✅ Drop-In📋 Reference alternative (not in catalog)
ATMEGA8515-16MU
✅ Drop-In✓ In Stock
$2.12 / Unit
View Datasheet →ATMEGA8535-16MU Maximum Ratings & Electrical Characteristics
| Core | AVR 8-bit RISC |
| Flash Memory | 8 KB (4K x 16) In-System Programmable |
| SRAM | 512 B |
| EEPROM | 512 B |
| Clock Speed | 16 MHz |
| Throughput | 16 MIPS at 16 MHz |
| Supply Voltage | 4.5 V to 5.5 V |
| ADC | 8-channel, 10-bit |
| I/O Ports | 23 (per digichip listing); 32 general purpose I/O lines per Microchip datasheet |
| Timers | Three Timer/Counters with compare modes |
| Serial Interfaces | USART, Two-wire Serial Interface (TWI) |
| Instructions | 130 powerful instructions, most single-cycle |
| Package | 44-VQFN (7x7 mm, 0.8 mm pitch) |
| Mounting Type | Surface Mount |
ATMEGA8535-16MU 44-vqfn (7x7 mm, 0.8 mm pitch) Pin Configuration Guide
Pin configuration for ATMEGA8535-16MU (44-vqfn (7x7 mm, 0.8 mm pitch) 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 ATMEGA8535-16MU.
Refer to the datasheet for full pin configuration.
Typical Applications
ATMEGA8535-16MU is suitable for 6 applications: Industrial Automation Control Nodes, Multi-Channel Sensor Acquisition, Embedded Motor Control, Legacy AVR Product Continuity, Serial Communication Gateways, Instrumentation and Test Rigs.
Industrial Automation Control Nodes
The ATMEGA8535-16MU fits industrial automation nodes because its 4.5-5.5 V supply tolerates noisy factory-floor power rails better than 3.3 V MCUs, and its three Timer/Counters with compare modes generate PWM for actuators at up to 16 MIPS. In a typical node it reads limit switches and encoders on its general purpose I/O lines, executes the control loop in the 8 KB Flash program, and reports status over the USART. The 512 B EEPROM stores station configuration through power cycles. Trade-off: 512 B SRAM limits buffering, so keep state machines lean and avoid large log buffers in RAM.
Recommended
Multi-Channel Sensor Acquisition
The on-chip 8-channel 10-bit ADC makes the ATMEGA8535-16MU well suited for multi-sensor acquisition: up to eight analog inputs (temperature, pressure, potentiometers) are multiplexed into a single 10-bit converter, saving an external ADC and board area. Sampled values feed a 16 MIPS control or averaging loop in Flash, with calibration constants held in 512 B EEPROM. Running at 16 MHz from 5 V improves ADC noise margins in electrically harsh settings. Performance consideration: the ADC reference and sampling capacitor require adequate settling time per channel switch, so sequence channels with dummy conversions in fast-scan applications.
Recommended
Embedded Motor Control
Motor control exploits the ATMEGA8535-16MU's three Timer/Counters in compare (PWM) mode to drive H-bridges or stepper drivers, while the 10-bit ADC reads current-sense or potentiometer feedback for closed-loop speed control. At 16 MHz the core executes PID updates well within typical PWM periods for small DC motors, and the 5 V I/O directly gates many gate-driver inputs. According to the Microchip datasheet, compare modes offload waveform generation from software, reducing jitter. Designers should budget the 512 B SRAM carefully for control-state and filter coefficients in multi-axis designs.
Recommended
Legacy AVR Product Continuity
For existing products designed around the ATmega8535, the -16MU in 44-VQFN preserves PCB footprint, codebase, and toolchain compatibility with zero redesign. The 8 KB In-System Programmable Flash with Read-While-Write allows field firmware updates over the SPI ISP interface without removing the device, and the AVR instruction set ensures object-level continuity with earlier builds. Sourcing the same-family variants (16MI, 16MUR) mitigates allocation risk. The trade-off is that this is a maintenance play, not a performance upgrade; plan a migration path to newer AVR parts for future feature growth.
Recommended
Serial Communication Gateways
The byte-oriented USART and the Two-wire Serial Interface (TWI, I2C-compatible) let the ATMEGA8535-16MU act as a protocol bridge between RS-232/RS-485 field buses and I2C peripherals such as EEPROMs, RTCs, and displays. At 16 MHz the core sustains respectable UART baud rates with margin for framing and checksum processing in software. The 5 V logic levels simplify interfacing with legacy industrial serial transceivers. Watch out for SRAM limits when implementing multi-slave TWI buffers, and use hardware-level UART interrupts described in the Microchip datasheet to avoid byte-loss at high baud rates.
Recommended
Instrumentation and Test Rigs
Bench instruments and production test rigs benefit from the ATMEGA8535-16MU's combination of 10-bit ADC for measurement, timer compare outputs for stimulus generation, and USART for PC communication. The single-cycle 130-instruction AVR core gives deterministic timing useful in pass/fail sequencing, and the 512 B EEPROM stores calibration tables that survive power cycles. In a typical rig it reads analog DUT outputs, applies threshold logic, and streams results over serial at 5 V logic levels compatible with legacy lab hardware. For finer resolution than 10 bits, add an external delta-sigma ADC via the TWI bus.
Recommended
Recommended Products Summary
Engineering reference data for ATMEGA8535-16MU — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATMEGA8535-16MI | ATMEGA8535-16MUR | ATMEGA8515-16MU | ATMEGA8535-16AU |
|---|---|---|---|---|---|
| Package | 44-VQFN (7x7 mm) | 44-VQFN (7x7 mm) - same | 44-VQFN (7x7 mm) - same | 44-VQFN (7x7 mm) - same | 44-TQFP - different footprint |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash | 8 KB | 8 KB | 8 KB | 8 KB | 8 KB |
| Clock Speed | 16 MHz | 16 MHz | 16 MHz | 16 MHz | 16 MHz |
| ADC | 8-channel 10-bit | 8-channel 10-bit | 8-channel 10-bit | None | 8-channel 10-bit |
| SRAM / EEPROM | 512 B / 512 B | 512 B / 512 B | 512 B / 512 B | 512 B / 512 B | 512 B / 512 B |
| Supply Voltage | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 4.5 V to 5.5 V |
| Lifecycle | Active | Active | Active | Active | Active (functional equivalent per Abacus) |
Key Differentiators
- On-chip 8-channel 10-bit ADC (vs ATMEGA8515-16MU)
- Identical silicon in industrial temperature grade (vs ATMEGA8535-16MI)
- 5 V noise immunity at 16 MIPS (vs Modern 3.3 V MCUs)
Design Notes
The -16 speed grade is specified only for 4.5 V to 5.5 V per the Microchip datasheet. Do not power it from a 3.3 V rail expecting 16 MHz operation - Brown-out resets or timing violations will result. Provide a regulated 5 V rail with at least 100 nF decoupling on each supply pin pair plus a bulk 10 uF capacitor near the IC. If brown-out detection is enabled, set the threshold appropriate to the 4.5 V floor so the MCU does not execute corrupted code during rail sag events.
The 44-VQFN (7x7 mm, 0.8 mm pitch) exposes pads under the package; verify your footprint against the datasheet mechanical drawing and include the center thermal pad per the Microchip recommended land pattern. Because the center pad may be internally connected to ground, tie it to a solid ground plane with an array of vias - this improves both signal integrity of the ADC ground reference and rework access. Use 0.8 mm pitch stencil apertures per IPC guidance to avoid bridging during reflow.
Common pitfalls: (1) assuming ATMEGA8515-16MU is a full substitute - it lacks the 8-channel ADC, so analog firmware will fail; (2) forgetting the ADC reference configuration - accuracy of the 10-bit converter depends on a clean AVCC/AREF, so filter AVCC with an LC network; (3) exceeding EEPROM endurance with frequent calibration writes - 512 B EEPROM is rated for limited write cycles, so wear-level configuration writes; (4) mixing up MU (VQFN) and AU/PJ (TQFP/PLCC) suffixes when ordering - they are not footprint interchangeable.
Compliance Information
Compliance status not stated in the provided verified web data. Similar Microchip ATmega parts are typically RoHS compliant; verify on the official Microchip product page before procurement.
