ATMEGA162L-8AC - 8MHz AVR MCU 16KB Flash TQFP-44 | Microchip
MPN: ATMEGA162L-8AC ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $6.9 | $6.90 |
| 10 | $6.21 | $62.10 |
| 100 | $5.52 | $552.00 |
| 500 | $4.97 | $2,485.00 |
| 1,000 | $4.48 | $4,480.00 |
ATMEGA162L-8AC Overview
An 8-bit AVR microcontroller is a single-chip processor based on the AVR enhanced RISC architecture, which executes most of its 131 powerful instructions in a single clock cycle, achieving throughput close to 1 MIPS per MHz. Within the embedded system hierarchy, the MCU sits at the control layer, integrating program memory (Flash), data memory (SRAM), nonvolatile storage (EEPROM), and peripherals such as UARTs, timers, SPI, and an ADC into one device, reducing board count versus discrete logic designs.
Key features include 16KB (8K x 16) self-programmable Flash, 1KB internal SRAM, 512B EEPROM, two 8-bit and one 16-bit timer with PWM capability, two hardware USARTs for dual serial channels, SPI and TWI (I2C) serial interfaces, a 10-bit ADC with up to 8 multiplexed single-ended channels, an on-chip JTAG boundary-scan and debug port, and an external memory interface supporting up to 64KB of optional external SRAM.
Architecturally, the ATmega162 pairs the AVR RISC core with a Harvard-structured memory bus, so instruction fetch and data access occur in parallel. In-system programmability lets firmware be updated after board assembly through SPI, while the JTAG port supports on-chip debugging and boundary-scan testing per the IEEE 1149.1 method used in the AVR family. The low-voltage L variant is rated for operation from 2.7V to 5.5V, suiting 3.3V systems.
Typical applications include industrial control panels, dual-UART communication gateways, building automation nodes, and legacy AVR designs where 5V-tolerant I/O, JTAG debug, and dual serial ports are required. The 35 I/O lines comfortably drive keys, relays, and LED indicators directly.
Design consideration: the L suffix limits safe clocking to 8MHz; to hit 16MHz you must migrate to the ATMEGA162-16AC/AU grade at 4.5V to 5.5V. Keep the RESET pin and JTAG fuse settings in mind during layout.
This page synthesizes distributor pricing, drop-in alternatives, pinout, and practical design notes not found in the manufacturer datasheet alone.
Drop-in alternatives for ATMEGA162L-8AC — 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 ATMEGA162L-8AC (same form factor and footprint) — differing in Core Architecture, EEPROM, I/O Pins, Package.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ATMEGA162L-8AU
✅ Drop-In ⚠️ 参数待验证📋 Reference alternative (not in catalog)
ATMEGA162-16AU
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$2.45 / Unit
View Datasheet →ATMEGA162-16AI
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$2.98 / Unit
View Datasheet →ATMEGA16-16AU
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$4.41 / Unit
View Datasheet →ATMEGA16L-8AU
✅ Drop-In ⚠️ 参数待验证📋 Reference alternative (not in catalog)
ATMEGA162L-8AC Maximum Ratings & Electrical Characteristics
| Core Architecture | AVR 8-bit RISC |
| Flash Program Memory | 16KB (8K x 16), In-System Programmable |
| SRAM Data Memory | 1KB |
| EEPROM | 512B |
| Maximum Clock Frequency | 8MHz |
| Instructions | 131, most single-cycle |
| I/O Pins | 35 |
| Timers | Two 8-bit + one 16-bit |
| USART Count | 2 |
| SPI | Yes, 1 channel |
| TWI (I2C) | Yes, 1 channel |
| ADC Resolution | 10-bit |
| JTAG | On-chip debug and boundary scan |
| Package | 44-TQFP (10x10 mm) |
| Mounting Type | Surface Mount |
| Terminal Form | Gull Wing |
| Temperature Grade | Commercial (AC suffix) |
| External Memory Interface | Up to 64KB external SRAM |
ATMEGA162L-8AC Pin Configuration
| Pin 1 | PB0/XCK/T0 — Port B bit 0; USART0 external clock / Timer0 external clock |
| Pin 2 | PB1/T1 — Port B bit 1; Timer1 external clock input |
| Pin 3 | PB2/AIN0/INT2 — Port B bit 2; analog comparator input 0 / external interrupt 2 |
| Pin 4 | PB3/AIN1/OC0 — Port B bit 3; analog comparator input 1 / Timer0 PWM output |
| Pin 5 | PB4/SS — Port B bit 4; SPI slave select |
| Pin 6 | PB5/MOSI — Port B bit 5; SPI master output / slave input |
| Pin 7 | PB6/MISO — Port B bit 6; SPI master input / slave output |
| Pin 8 | PB7/SCK/OC2 — Port B bit 7; SPI clock / Timer2 PWM output |
| Pin 9 | RESET — Active-low reset input |
| Pin 10 | VCC — Digital supply voltage |
| Pin 11 | GND — Ground |
| Pin 12 | XTAL2 — Inverting oscillator amplifier output |
| Pin 13 | XTAL1 — Inverting oscillator amplifier input / external clock input |
| Pin 14 | PD0/RXD0 — Port D bit 0; USART0 receive |
| Pin 15 | PD1/TXD0 — Port D bit 1; USART0 transmit |
| Pin 16 | PD2/INT0 — Port D bit 2; external interrupt 0 |
| Pin 17 | PD3/INT1 — Port D bit 3; external interrupt 1 |
| Pin 18 | PD4/XCK1 — Port D bit 4; USART1 external clock |
| Pin 19 | PD5/OC1A — Port D bit 5; Timer1 output compare A / PWM |
| Pin 20 | PD6/ICP1 — Port D bit 6; Timer1 input capture |
| Pin 21 | PD7/OC1B — Port D bit 7; Timer1 output compare B / PWM |
| Pin 22 | PC0/TMS — Port C bit 0; JTAG test mode select (when JTAG enabled) |
| Pin 23 | PC1/TDO — Port C bit 1; JTAG test data output (when JTAG enabled) |
| Pin 24 | PC2/TCK — Port C bit 2; JTAG test clock (when JTAG enabled) |
| Pin 25 | PC3/TDI — Port C bit 3; JTAG test data input (when JTAG enabled) |
| Pin 26 | PC4 — Port C bit 4; general purpose I/O / external memory address line |
| Pin 27 | PC5 — Port C bit 5; general purpose I/O / external memory address line |
| Pin 28 | PC6 — Port C bit 6; general purpose I/O / external memory address line |
| Pin 29 | PC7 — Port C bit 7; general purpose I/O / external memory address line |
| Pin 30 | AVCC — ADC supply voltage |
| Pin 31 | GND — Ground |
| Pin 32 | AREF — ADC reference voltage |
| Pin 33 | PA0/AD0 — Port A bit 0; ADC channel 0 / external memory data bus bit 0 |
| Pin 34 | PA1/AD1 — Port A bit 1; ADC channel 1 / external memory data bus bit 1 |
| Pin 35 | PA2/AD2 — Port A bit 2; ADC channel 2 / external memory data bus bit 2 |
| Pin 36 | PA3/AD3 — Port A bit 3; ADC channel 3 / external memory data bus bit 3 |
| Pin 37 | PA4/AD4 — Port A bit 4; ADC channel 4 / external memory data bus bit 4 |
| Pin 38 | PA5/AD5 — Port A bit 5; ADC channel 5 / external memory data bus bit 5 |
| Pin 39 | PA6/AD6 — Port A bit 6; ADC channel 6 / external memory data bus bit 6 |
| Pin 40 | PA7/AD7 — Port A bit 7; ADC channel 7 / external memory data bus bit 7 |
| Pin 41 | PE0/RXD1/PDI — Port E bit 0; USART1 receive |
| Pin 42 | PE1/TXD1/PDO — Port E bit 1; USART1 transmit |
| Pin 43 | PE2 — Port E bit 2; general purpose I/O (per datasheet) |
| Pin 44 | GND — Ground (per datasheet) |
Typical Applications
ATMEGA162L-8AC is suitable for 6 applications: Industrial Control Panels, Dual-UART Communication Gateways, Building Automation Nodes, Legacy AVR Product Maintenance, Instrumentation and Data Loggers, Motor and PWM Control.
Industrial Control Panels
The ATMEGA162L-8AC fits industrial control and automation panels where 35 I/O lines drive keys, indicators, relays, and opto-isolated inputs directly. The 10-bit ADC reads potentiometers and analog sensor channels, while three timers generate PWM outputs for actuator or heater control. Its 16KB Flash accommodates state-machine logic and communication stacks, and the external memory interface allows SRAM expansion to 64KB if datalogging grows. Because the device is a mature, widely second-sourced AVR in TQFP-44, long-term maintainability of control panel designs is a practical advantage over newer, more volatile part lines.
Recommended
Dual-UART Communication Gateways
With two independent hardware USARTs, the ATMEGA162L-8AC is a natural protocol gateway: one port links to an RS-485 multidrop field bus while the other provides an RS-232 service or diagnostics channel. At 8MHz the AVR core sustains multi-byte buffered serial handling with interrupt-driven ring buffers in the 1KB SRAM. The 512B EEPROM stores node addresses and configuration parameters across power cycles. Compared to bit-banging a second UART on a single-UART device, the second hardware USART eliminates timing jitter, making this part the preferred choice for Modbus-style converters and legacy serial bridges.
Recommended
Building Automation Nodes
In building automation, the ATMEGA162L-8AC serves as a room-controller node combining the TWI (I2C) bus for sensors and displays, the 10-bit ADC for temperature and light-level inputs, and a USART for panel networking. The low-voltage L grade supports 3.3V designs common in modern sensor wiring, while the JTAG port enables in-system firmware updates during commissioning. Its 8MHz clock keeps dynamic power low for continuously powered nodes, and in-system programmable Flash lets field technicians re-flash schedules or setpoints without desoldering the MCU, reducing service cost over installation lifetime.
Recommended
Legacy AVR Product Maintenance
Many legacy products were designed around the ATmega162 family, and the ATMEGA162L-8AC remains the designated replacement for boards with this footprint. Because the die, 44-TQFP package, and pinout are unchanged across the family (ATMEGA162L-8AC/8AU/16AC/16AU/16AI), service organizations can stock one physical footprint and select the grade per environment. The JTAG debug port supports re-entering old code bases for defect analysis, and SPI in-system programming works with existing production fixtures. For end-of-life service inventories, cross-qualifying the L-8 and 16MHz grades maximizes sourcing resilience with a single board layout.
Recommended
Instrumentation and Data Loggers
The ATMEGA162L-8AC suits compact measurement instruments: the 10-bit ADC digitizes sensor channels, timers capture pulse inputs or generate precise sampling intervals, and the dual USARTs send data to both a display controller and a host PC simultaneously. The external memory interface expands RAM to 64KB for buffered datalogging beyond the internal 1KB SRAM, a differentiator versus smaller AVRs. The 512B EEPROM holds calibration constants that survive power loss. With JTAG boundary scan on port C, production test can verify board interconnects before firmware is even loaded, improving first-pass yield on small instrument runs.
Recommended
Motor and PWM Control
For small motor and actuator control, the ATMEGA162L-8AC provides hardware PWM via its timer compare outputs (including OC1A/OC1B channels), enabling closed-loop speed control when combined with ADC feedback from encoders or shunt sensors. The external interrupt pins (INT0/INT1/INT2) accept tachometer pulses, and the 16-bit timer measures period precisely. Two USARTs allow simultaneous command input and telemetry output. At 8MHz, the core executes control-loop math with microsecond-scale latency, sufficient for DC motor and brushless fan control, while the gull-wing TQFP-44 package simplifies automated assembly on control PCBs.
Recommended
Recommended Products Summary
Engineering reference data for ATMEGA162L-8AC — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATMEGA162L-8AU | ATMEGA162-16AU | ATMEGA162-16AI | ATMEGA16-16AU | ATMEGA16L-8AU |
|---|---|---|---|---|---|---|
| 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 | 8MHz | 8MHz | 16MHz | 16MHz | 16MHz | 8MHz |
| Flash Memory | 16KB ISP Flash | 16KB | 16KB | 16KB | 16KB | 16KB |
| SRAM | 1KB | 1KB | 1KB | 1KB | 1KB | 1KB |
| USART Count | 2 | 2 | 2 | 2 | 1 | 1 |
| Temperature Range | Commercial (AC) | Industrial (-40C to +85C) | Industrial (-40C to +85C) | Industrial (-40C to +85C) | Industrial (-40C to +85C) | Industrial (-40C to +85C) |
| I/O Pins | 35 | 35 | 35 | 35 | 32 | 32 |
Key Differentiators
- Dual hardware USARTs in a 44-pin package (vs ATMEGA16-16AU)
- Low-voltage 3.3V operation (vs ATMEGA162-16AU)
- External memory interface up to 64KB SRAM (vs ATMEGA16-16AU)
- Trade-off: lower maximum clock speed (vs ATMEGA162-16AU)
Design Notes
The L (low-voltage) grade of the ATMEGA162L-8AC must not be clocked beyond 8MHz; the frequency/voltage safe-operating relationship in AVR datasheets restricts maximum frequency at reduced VCC. If your board must run at 16MHz, populate the ATMEGA162-16AU/16AC grade instead (5V operation). Decouple VCC and AVCC separately with 100nF ceramics placed within a few millimeters of pins 10 and 30, and tie AREF to a clean reference through a 100nF capacitor when the ADC is used. Estimated: at 8MHz and 3.3V, active current is on the order of a few mA per AVR family figures - verify exact value in the manufacturer datasheet.
Keep the crystal (XTAL1/XTAL2, pins 13/12) as close to the device as possible with short traces and guard with a ground ring to minimize stray capacitance; external crystal load capacitors must match the crystal specification for accurate USART baud rates. Route the JTAG pins (PC0-PC3) to a 2x5 header if in-system debugging is planned, since retrofitting later requires bodge wires. If port C is fully used as I/O or external address lines, remember to disable JTAG via fuse, otherwise four pins are unavailable after reset.
Two frequent mistakes with this part: first, assuming ATMEGA16 code drops onto ATMEGA162 - the second USART and peripheral register maps differ, so firmware must be recompiled and retested. Second, leaving RESET (pin 9) undriven; use a 10k pull-up and consider external reset supervision for industrial environments. When using the external memory interface, ports A and C are consumed by the data/address bus, reducing general I/O significantly. Finally, verify the AC (commercial) temperature grade matches your operating environment; the AU suffix parts extend to -40C to +85C.
Compliance Information
Compliance status not stated in the retrieved web data. The AU-suffix ATmega162 variants are typically the RoHS/green package options; verify compliance on the official Microchip product page before procurement.
