ATMEGA8515L-8PI - 8-bit AVR MCU 8KB Flash 40-DIP | Microchip
MPN: ATMEGA8515L-8PI β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $5.2 | $5.20 |
| 10 | $4.7 | $47.00 |
| 100 | $4.25 | $425.00 |
| 500 | $3.85 | $1,925.00 |
| 1,000 | $3.45 | $3,450.00 |
ATMEGA8515L-8PI Overview
A microcontroller is a single-chip computer that integrates a processor core, program memory, data memory, and peripherals on one die. The ATMEGA8515L sits in the 8-bit microcontroller hierarchy: AVR core -> 8-bit MCU -> embedded processor, a class widely used for embedded control in appliances, industrial equipment, and hobby electronics.
Key features include the AVR enhanced RISC architecture with 130 powerful instructions, most executing in a single clock cycle, and 32 general-purpose working registers that deliver up to 1 MIPS per MHz throughput. The L-grade part operates from 2.7 V to 5.5 V, making it suitable for both 3.3 V and 5 V systems. The external memory interface (ALE, RD, WR, multiplexed address/data on Ports A and C) differentiates it from smaller AVRs such as the ATmega8.
Technically, the device is fully static, allowing clock frequencies down to DC without state loss. Peripherals include one 16-bit timer and 8-bit timers, a USART, SPI interface, and three external interrupt sources; notably, the ATmega8515 family has no internal ADC, which is a key selection consideration versus the ATmega8/ATmega32 families.
Typical applications include legacy 8051-pinout replacement designs, industrial control boards, external-memory-expansion systems, and educational or laboratory platforms where through-hole 40-DIP packaging simplifies prototyping and socket-based field replacement.
Design consideration: at 5 V and 8 MHz, keep the power supply within the 4.5 V to 5.5 V full-speed window; below 4.5 V the maximum safe clock frequency must be derated per the AVR frequency-voltage curve in the manufacturer datasheet.
This page synthesizes distributor pricing, drop-in alternatives, a full 40-pin pinout, and practical design notes not found together on the manufacturer product page.
Drop-in alternatives for ATMEGA8515L-8PI 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 ATMEGA8515L-8PI (same form factor and footprint) β differing in Operating Temperature, Package, Core Architecture, External Memory Support, Instruction Set.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
No drop-in alternatives available for this product.
Request AlternativesATMEGA8515L-8PI Maximum Ratings & Electrical Characteristics
| Core Architecture | 8-bit AVR enhanced RISC |
| Instruction Set | 130 instructions, most single-cycle |
| Flash Program Memory | 8 KB (4K x 16), In-System Programmable |
| EEPROM | 512 B |
| Internal SRAM | 512 B |
| External Memory Support | Up to 64 KB SRAM |
| General Purpose I/O | 35 programmable I/O lines |
| Maximum Clock Frequency | 8 MHz |
| Throughput | Up to 8 MIPS at 8 MHz |
| Operating Voltage Range | 2.7 V to 5.5 V |
| Timers | One 16-bit (T1) and 8-bit Timer/Counters |
| Serial Interfaces | 1x USART, 1x SPI |
| External Interrupts | 3 (INT0-INT2) |
| Internal ADC | No |
| Debug/Programming | ISP via SPI; debug via MPLAB SNAP |
| Operating Temperature | -40C to +85C (Industrial) |
| Package | 40-PDIP (0.600 in, 15.24 mm) |
| Mounting Type | Through Hole |
ATMEGA8515L-8PI Pin Configuration
| Pin 1 | PB0/XCK/T0 β Port B bit 0 / USART external clock / Timer0 external clock |
| Pin 2 | PB1/T1 β Port B bit 1 / Timer1 external clock |
| Pin 3 | PB2/AIN0 β Port B bit 2 / analog comparator input 0 |
| Pin 4 | PB3/AIN1 β Port B bit 3 / analog comparator input 1 |
| Pin 5 | PB4/SS β Port B bit 4 / SPI slave select |
| Pin 6 | PB5/MOSI β Port B bit 5 / SPI master output |
| Pin 7 | PB6/MISO β Port B bit 6 / SPI master input |
| Pin 8 | PB7/SCK β Port B bit 7 / SPI serial clock |
| Pin 9 | RESET β Active-low reset input |
| Pin 10 | PD0/RXD β Port D bit 0 / USART receive data |
| Pin 11 | PD1/TXD β Port D bit 1 / USART transmit data |
| Pin 12 | PD2/INT0 β Port D bit 2 / external interrupt 0 |
| Pin 13 | PD3/INT1 β Port D bit 3 / external interrupt 1 |
| Pin 14 | PD4/XCK β Port D bit 4 / external memory-related clock/function |
| Pin 15 | PD5/OC1A β Port D bit 5 / Timer1 output compare A |
| Pin 16 | PD6/WR β Port D bit 6 / external memory write strobe |
| Pin 17 | PD7/RD β Port D bit 7 / external memory read strobe |
| Pin 18 | XTAL2 β Crystal oscillator output |
| Pin 19 | XTAL1 β Crystal oscillator input / external clock |
| Pin 20 | GND β Ground |
| Pin 21 | PC0/A8 β Port C bit 0 / external memory address bit 8 |
| Pin 22 | PC1/A9 β Port C bit 1 / external memory address bit 9 |
| Pin 23 | PC2/A10 β Port C bit 2 / external memory address bit 10 |
| Pin 24 | PC3/A11 β Port C bit 3 / external memory address bit 11 |
| Pin 25 | PC4/A12 β Port C bit 4 / external memory address bit 12 |
| Pin 26 | PC5/A13 β Port C bit 5 / external memory address bit 13 |
| Pin 27 | PC6/A14 β Port C bit 6 / external memory address bit 14 |
| Pin 28 | PC7/A15 β Port C bit 7 / external memory address bit 15 |
| Pin 29 | PE0/ICP β Port E bit 0 / Timer1 input capture |
| Pin 30 | PE1/ALE β Port E bit 1 / external memory address latch enable |
| Pin 31 | PE2 β Port E bit 2 / general purpose I/O |
| Pin 32 | PA0/AD0 β Port A bit 0 / external memory address-data bit 0 |
| Pin 33 | PA1/AD1 β Port A bit 1 / external memory address-data bit 1 |
| Pin 34 | PA2/AD2 β Port A bit 2 / external memory address-data bit 2 |
| Pin 35 | PA3/AD3 β Port A bit 3 / external memory address-data bit 3 |
| Pin 36 | PA4/AD4 β Port A bit 4 / external memory address-data bit 4 |
| Pin 37 | PA5/AD5 β Port A bit 5 / external memory address-data bit 5 |
| Pin 38 | PA6/AD6 β Port A bit 6 / external memory address-data bit 6 |
| Pin 39 | PA7/AD7 β Port A bit 7 / external memory address-data bit 7 |
| Pin 40 | VCC β Supply voltage (2.7 V to 5.5 V) |
Typical Applications
ATMEGA8515L-8PI is suitable for 6 applications: Legacy 8051 Socket Upgrade, External Memory Expansion Systems, Industrial Control Boards, Educational and Laboratory Platforms, Embedded Communication Nodes, Test Fixtures and Production Jigs.
Legacy 8051 Socket Upgrade
The ATMEGA8515L-8PI was designed to be pin-compatible with the industry-standard 8051 40-pin PDIP footprint, including VCC on pin 40, GND on pin 20, and the crystal on pins 18 and 19, so legacy 8051 control boards can be upgraded by replacing the chip and rewriting firmware. Its 130-instruction AVR RISC core delivers up to 8 MIPS at 8 MHz, roughly an order of magnitude more throughput per clock than a standard 8051 at similar frequencies, while the 2.7 V to 5.5 V L-grade supply range tolerates aging 5 V rails. Designers must port the 8051 memory map to AVR addressing, but the external bus interface (ALE, RD, WR) keeps latch-based bus expansion schemes intact.
Recommended
External Memory Expansion Systems
With 512 B of internal SRAM, the ATMEGA8515L-8PI relies on its built-in external memory interface for data-intensive tasks: Ports A and C provide the multiplexed address/data bus while PE1 (ALE), PD6 (WR), and PD7 (RD) control up to 64 KB of external SRAM. The 8 MHz L-grade clock keeps bus timing relaxed, allowing inexpensive 150 ns SRAM devices without wait-state tuning. Typical uses include data loggers and protocol buffers where 64 KB of RAM exceeds what most 8-bit AVRs can address. The trade-off versus ADC-equipped AVRs is that most Port A pins are consumed by the bus, so analog inputs require an external SPI ADC.
Recommended
Industrial Control Boards
The -40C to +85C industrial temperature rating and 2.7 V to 5.5 V supply tolerance make the ATMEGA8515L-8PI suitable for factory control panels, motor start logic, and sensor polling nodes exposed to wide ambient swings. The USART supports RS-485 networked control via an external transceiver, and SPI connects real-time clocks or isolated I/O expanders. Three external interrupt sources (INT0-INT2) handle safety interlocks. At 8 MHz the device delivers 8 MIPS, adequate for deterministic polling loops under 1 ms. Designers should account for the absence of a watchdog-supplied brown-out guarantee at low VCC by verifying BOD fuse settings per the Microchip datasheet.
Recommended
Educational and Laboratory Platforms
The through-hole 40-pin PDIP package lets students and lab users socket the ATMEGA8515L-8PI on breadboards and training boards, replacing it without hot-air tools. The AVR instruction set of 130 mostly single-cycle instructions is widely documented, and ISP programming over SPI with an MPLAB SNAP or AVRISP-class tool requires only a 5-pin header. The external memory interface is a distinctive teaching feature, demonstrating address latching with a 74HC573 and memory-mapped I/O that simpler 28-pin AVRs cannot show. The 2.7 V to 5.5 V range also allows safe experiments at both 3.3 V and 5 V logic levels with a single part.
Recommended
Embedded Communication Nodes
For RS-232/RS-485 field nodes, the ATMEGA8515L-8PI pairs its hardware USART with SPI for secondary peripherals such as EEPROM, RTCs, and network transceivers. Running at 8 MHz gives comfortable baud-rate generation headroom for standard rates up to 115200 from the 8 MHz clock. The 512 B EEPROM stores node addresses and calibration constants through power cycles, while the 512 B internal SRAM (extendable externally to 64 KB) buffers message frames. In battery-backed or brownout-prone installations, the L-grade 2.7 V floor keeps the node alive on declining supply rails longer than standard 4.5 V minimum parts.
Recommended
Test Fixtures and Production Jigs
Production test jigs favor socketed through-hole controllers for rapid swap during fixture maintenance, making the 40-DIP ATMEGA8515L-8PI a practical jig brain. Its 35 I/O lines drive pass/fail indicators, relay muxes, and read back UUT signals directly; the 16-bit Timer/Counter measures pulse widths with 125 ns resolution at 8 MHz. Because jig firmware changes frequently, the self-programming ISP Flash allows field updates without removing the device. The industrial temperature range tolerates non-conditioned factory floors, and 2.7 V to 5.5 V operation accepts unregulated bench supplies within limits documented in the Microchip datasheet.
Recommended
Recommended Products Summary
Engineering reference data for ATMEGA8515L-8PI β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATMEGA8515L-8PU | ATMEGA8515L-8PJ | ATMEGA8515-16PI | ATMEGA8515-16PU | AT90S8515-8PI |
|---|---|---|---|---|---|---|
| Package | 40-PDIP (0.600 in, 15.24 mm) | 40-PDIP (0.600 in) - same | 40-PDIP (0.600 in) - same | 40-PDIP (0.600 in) - same | 40-PDIP (0.600 in) - same | 40-PDIP (0.600 in) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology (Atmel legacy) |
| Max Clock Frequency | 8 MHz | 8 MHz | 8 MHz | 16 MHz | 16 MHz | 8 MHz |
| Flash / EEPROM / SRAM | 8 KB / 512 B / 512 B | 8 KB / 512 B / 512 B | 8 KB / 512 B / 512 B | 8 KB / 512 B / 512 B | 8 KB / 512 B / 512 B | 8 KB / 512 B / 512 B (no self-programming) |
| Temperature Range | -40C to +85C (I grade) | 0C to +70C (C grade) | -40C to +85C (I grade) | -40C to +85C (I grade) | 0C to +70C (C grade) | -40C to +85C (I grade) |
| External Memory Interface | Yes, up to 64 KB | Yes, up to 64 KB | Yes, up to 64 KB | Yes, up to 64 KB | Yes, up to 64 KB | Yes, up to 64 KB |
| Lifecycle Status | Active | Active | Active | Active | Active | Obsolete (EOL) |
Key Differentiators
- Widest supply range in the ATmega8515 DIP family (vs ATMEGA8515-16PI)
- Industrial temperature rating at low cost (vs ATMEGA8515L-8PU)
- External memory interface up to 64 KB (vs ATMEGA8-16PI)
Design Notes
The L-grade device supports 2.7 V to 5.5 V, but full 8 MHz operation is only guaranteed near the upper supply range. Per the AVR frequency-vs-VCC relationship in the manufacturer datasheet, if your board runs at 3.3 V you must limit the clock below 8 MHz (estimate: roughly 4 MHz at 3.3 V, using the classic AVR safe-operating rule of about 1 MHz per volt for the L-grade family). For a 3.3 V design needing full speed, choose a different AVR family rather than overclocking this part. Verify brown-out detector fuse settings so supply dips below 2.7 V trigger a clean reset.
Place a 100 nF ceramic decoupling capacitor directly across VCC (pin 40) and GND (pin 20), plus a 10 uF bulk capacitor near the socket. Because the DIP package has power pins at opposite corners of the package diagonal, keep the ground return path short on through-hole layouts. For the external memory interface, route Port A (AD0-AD7) and Port C address lines with matched lengths where practical, and use a 74HC573 latch clocked by PE1 (ALE) to demultiplex the address bus. Add 10 k-33 k pull-up on RESET (pin 9) for reliable power-on reset with an external supervisor.
The most common selection error is assuming all ATmega parts include an ADC: the ATmega8515 family has none. If analog inputs are needed, budget an external SPI ADC or select another family. Second pitfall: the 8051-compatible pinout is NOT identical to the ATmega32/ATmega16 40-DIP pinout (different VCC/GND and port placement), so do not swap devices between those footprints. Third, reserve PB5-PB7 and PB4 during PCB layout if ISP programming is required; permanently loading these SPI pins can block field firmware updates.
Compliance Information
Compliance status not stated in the provided web data. The -PJ package suffix in the ATmega8515 family is the green (RoHS/Pb-free) variant; verify the -PI suffix compliance on the official Microchip product page before specifying.
