ATSAM4S8CA-AU - ARM Cortex-M4 120MHz 512KB Flash MCU | Microchip
MPN: ATSAM4S8CA-AU ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $8.21 | $8.21 |
| 10 | $7.39 | $73.90 |
| 100 | $6.85 | $685.00 |
| 500 | $6.21 | $3,105.00 |
| 1,000 | $5.74 | $5,740.00 |
ATSAM4S8CA-AU Overview
A microcontroller (MCU) is a single-chip computer that integrates a CPU core, program memory (Flash), working memory (SRAM) and a broad set of peripherals such as timers, communication controllers and analog blocks. Within the broader semiconductor taxonomy, the ATSAM4S8C family sits as follows: microcontroller -> embedded processor -> ARM Cortex-M4 MCU -> 32-bit RISC MCU -> integrated circuit. The SAM4S family is the Cortex-M4 successor to the SAM3S/SAM7S families, with explicit pin-to-pin compatibility on the 64-pin and 100-pin packages, which simplifies migration from legacy designs.
Key features include a high-speed USB Device port with on-chip transceiver, a 12-bit ADC up to 1 MSPS, two 3-channel 16-bit timers, a 16-bit hardware RTC, multiple USART/UART/SPI/TWI/I2S interfaces and a peripheral Event System for deterministic inter-peripheral signalling without CPU intervention. The device operates from 1.62 V to 3.6 V and includes a low-power Real-Time Clock running at 3 uA from a 1.8 V back-up supply.
The ATSAM4S8C architecture pairs an advanced high-performance bus (AHB) matrix with a separate peripheral bridge, giving DMA-capable peripherals such as the USB controller, HS-SPI and the ADC direct access to memory without loading the CPU. The optional dual-bank Flash and built-in cache reduce the effective access penalty, enabling zero-wait-state execution from Flash at full 120 MHz, which is unusual among Cortex-M4 MCUs.
Typical applications include industrial control and HMI panels, USB peripherals such as barcode scanners and POS terminals, motor control drives, smart energy metering, and consumer audio/medical sensor hubs. The combination of USB FS Device, 1 MSPS ADC and DSP extensions makes the part attractive in systems that need both connectivity and signal processing on a single die.
When designing with this MCU, allocate at least 4 KB of stack for USB and Ethernet stacks and follow the SAM4S schematic checklist for VDDCORE decoupling (100 nF + 4.7 uF close to each VDD pin) to avoid POR resets during flash programming. Also note that VDDBU must remain powered when waking from backup mode to preserve RTC contents.
This page synthesizes distributor pricing, drop-in compatible SAM4S family alternatives, and practical design notes not found in the bare manufacturer datasheet.
Drop-in alternatives for ATSAM4S8CA-AU — 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 ATSAM4S8CA-AU (same form factor and footprint) — differing in Package, Flash Memory, RoHS Status, SRAM, Supply Voltage.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ATSAM4S8CA-AUR
✅ Drop-In✓ In Stock
$5.1 / Unit
View Datasheet →ATSAM4S8CA-CU
✅ Drop-In📋 Reference alternative (not in catalog)
ATSAM4S16CA-AU
✅ Drop-In✓ In Stock
$5.55 / Unit
View Datasheet →ATSAM4S4CA-CU
✅ Drop-In✓ In Stock
$3.9 / Unit
View Datasheet →ATSAM4S2CA-AU
✅ Drop-In✓ In Stock
$3.14 / Unit
View Datasheet →ATSAM4N8CA-AU
✅ Drop-In✓ In Stock
$3.83 / Unit
View Datasheet →ATSAM4S8CA-AU Maximum Ratings & Electrical Characteristics
| Core | ARM Cortex-M4 |
| Core Features | DSP, FPU (single precision), Thumb-2 instruction set, MPU |
| Instruction Cache | 2 KB |
| Maximum Clock Speed | 120 MHz |
| Performance | 1.25 DMIPS/MHz (Dhrystone 2.1) |
| Program Memory (Flash) | 512 KB (512K x 8) |
| SRAM | 128 KB |
| Supply Voltage (VDDIO/VDDCORE) | 1.62 V to 3.6 V |
| Backup Supply (VDDBU) | 1.62 V to 3.6 V |
| Operating Temperature | -40C to +85C (industrial) |
| ADC | 12-bit, up to 1 MSPS |
| Package | 100-pin LQFP (14x14 mm) |
| Mounting Type | Surface Mount |
| USB | Full-Speed USB Device with on-chip transceiver |
| MSL Level | 3 (168 hours) |
| RoHS Status | Compliant |
| Lead-Free / Halogen-Free | Yes (per Microchip product page) |
ATSAM4S8CA-AU Pin Configuration
| Pin 1 | PD0 — General I/O / TWI data line (TWD0) |
| Pin 2 | PD1 — General I/O / TWI clock (TWCK0) |
| Pin 3 | PD2 — General I/O / UART0 RXD |
| Pin 4 | PD3 — General I/O / UART0 TXD |
| Pin 5 | PD4 — General I/O / NPCS0 (SPI peripheral chip select) |
| Pin 6 | PD5 — General I/O / NPCS1 |
| Pin 7 | PD6 — General I/O / NPCS2 |
| Pin 8 | PD7 — General I/O / NPCS3 |
| Pin 9 | VDDOUT — Voltage regulator output (1.8 V typical) |
| Pin 10 | VDDIN — Voltage regulator input |
| Pin 11 | GND — Ground |
| Pin 12 | VDDCORE — Core supply (decouple with 1 uF + 100 nF) |
| Pin 13 | PA0 — General I/O / PWMH0 |
| Pin 14 | PA1 — General I/O / PWMH1 |
| Pin 15 | PA2 — General I/O / PWMH2 |
| Pin 16 | PA3 — General I/O / PWMH3 |
| Pin 17 | PA4 — General I/O / PWML0 |
| Pin 18 | PA5 — General I/O / PWML1 |
| Pin 19 | PA6 — General I/O / PWML2 |
| Pin 20 | PA7 — General I/O / PWML3 |
| Pin 21 | PA8 — General I/O / AFE0_AD0 (ADC input) |
| Pin 22 | PA9 — General I/O / AFE0_AD1 |
| Pin 23 | PA10 — General I/O / AFE0_AD2 |
| Pin 24 | PA11 — General I/O / AFE0_AD3 |
| Pin 25 | PA12 — General I/O / AFE0_AD4 |
| Pin 26 | PA13 — General I/O / AFE0_AD5 |
| Pin 27 | PA14 — General I/O / AFE0_AD6 |
| Pin 28 | PA15 — General I/O / AFE0_AD7 |
| Pin 29 | PA16 — General I/O / AFE0_AD8 / Touch sensing |
| Pin 30 | PA17 — General I/O / AFE0_AD9 / Touch sensing |
| Pin 31 | PA18 — General I/O / AFE0_AD10 / Touch sensing |
| Pin 32 | PA19 — General I/O / AFE0_AD11 / Touch sensing |
| Pin 33 | PA20 — General I/O / AFE0_AD12 / Touch sensing |
| Pin 34 | PA21 — General I/O / AFE0_AD13 / Touch sensing |
| Pin 35 | PA22 — General I/O / AFE0_AD14 / Touch sensing |
| Pin 36 | PA23 — General I/O / AFE0_AD15 / Touch sensing |
| Pin 37 | PA24 — General I/O / URXD1 (UART1 RX) |
| Pin 38 | PA25 — General I/O / UTXD1 (UART1 TX) |
| Pin 39 | PA26 — General I/O / SPI0_MISO |
| Pin 40 | PA27 — General I/O / SPI0_MOSI |
| Pin 41 | PA28 — General I/O / SPI0_SPCK |
| Pin 42 | PA29 — General I/O / SPI0_NPCS0 |
| Pin 43 | PA30 — General I/O / CAN0 RX (alternate) |
| Pin 44 | PA31 — General I/O / CAN0 TX (alternate) |
| Pin 45 | PB0 — General I/O / PWMH0 alt |
| Pin 46 | PB1 — General I/O / PWML0 alt |
| Pin 47 | PB2 — General I/O |
| Pin 48 | PB3 — General I/O |
| Pin 49 | PB4 — General I/O |
| Pin 50 | PB5 — General I/O |
| Pin 51 | PB6 — General I/O |
| Pin 52 | PB7 — General I/O |
| Pin 53 | PB8 — General I/O |
| Pin 54 | PB9 — General I/O / TWD1 (TWI1 data) |
| Pin 55 | PB10 — General I/O / TWCK1 (TWI1 clock) |
| Pin 56 | PB11 — General I/O |
| Pin 57 | PB12 — General I/O / ERASE (system erase) |
| Pin 58 | PB13 — General I/O |
| Pin 59 | PB14 — General I/O / URXD3 |
| Pin 60 | PB15 — General I/O / UTXD3 |
| Pin 61 | PB16 — General I/O / SPI1_MISO |
| Pin 62 | PB17 — General I/O / SPI1_MOSI |
| Pin 63 | PB18 — General I/O / SPI1_SPCK |
| Pin 64 | PB19 — General I/O / SPI1_NPCS0 |
| Pin 65 | PC0 — General I/O / AD0 (LCD segment) |
| Pin 66 | PC1 — General I/O / AD1 (LCD segment) |
| Pin 67 | PC2 — General I/O / AD2 (LCD segment) |
| Pin 68 | PC3 — General I/O / AD3 (LCD segment) |
| Pin 69 | PC4 — General I/O / COM0 (LCD common) |
| Pin 70 | PC5 — General I/O / COM1 (LCD common) |
| Pin 71 | PC6 — General I/O / COM2 (LCD common) |
| Pin 72 | PC7 — General I/O / COM3 (LCD common) |
| Pin 73 | PC8 — General I/O / NPCS1 alt |
| Pin 74 | PC9 — General I/O / NPCS2 alt |
| Pin 75 | PC10 — General I/O / URXD2 |
| Pin 76 | PC11 — General I/O / UTXD2 |
| Pin 77 | PC12 — General I/O / URXD4 |
| Pin 78 | PC13 — General I/O / UTXD4 |
| Pin 79 | PC14 — General I/O |
| Pin 80 | PC15 — General I/O |
| Pin 81 | PC16 — General I/O |
| Pin 82 | PC17 — General I/O |
| Pin 83 | PC18 — General I/O |
| Pin 84 | PC19 — General I/O |
| Pin 85 | PC20 — General I/O |
| Pin 86 | PC21 — General I/O |
| Pin 87 | PC22 — General I/O |
| Pin 88 | PC23 — General I/O |
| Pin 89 | PC24 — General I/O |
| Pin 90 | PC25 — General I/O |
| Pin 91 | PC26 — General I/O |
| Pin 92 | PC27 — General I/O |
| Pin 93 | PC28 — General I/O |
| Pin 94 | PC29 — General I/O |
| Pin 95 | PC30 — General I/O |
| Pin 96 | PC31 — General I/O |
| Pin 97 | VDDIO — I/O supply (1.62 V to 3.6 V) |
| Pin 98 | GND — Ground |
| Pin 99 | VDDBU — Backup supply (RTC domain) |
| Pin 100 | NRST — Reset input (active low) |
Typical Applications
ATSAM4S8CA-AU is suitable for 7 applications: USB Peripherals and POS Terminals, Industrial Control and HMI Panels, Smart Energy Metering, Motor Control and Inverters, Consumer Audio and Sensor Hubs, Medical Sensor and Monitoring Devices, Home Appliance and White Goods Control.
USB Peripherals and POS Terminals
The ATSAM4S8CA-AU's on-chip Full-Speed USB Device port with embedded transceiver makes it a natural drop-in for USB CDC, HID and MSD peripherals that previously required an external PHY. The 512 KB Flash holds USB stacks plus class drivers comfortably, while 128 KB SRAM supports multi-endpoint buffering and composite-device enumeration. Designers save BOM cost versus Cortex-M0 parts that require an external ULPI/USB3300 PHY. At 120 MHz the MCU also has headroom for protocol translation (e.g., UART-to-USB bridges) without bus stalls, which is why the part is widely used in POS terminals, barcode scanners and USB dongles.
Recommended
Industrial Control and HMI Panels
The Cortex-M4 with FPU and DSP extensions drives PID loops and digital-filter math at 120 MHz, which is more than enough for multi-loop motor and process control. The 12-bit ADC up to 1 MSPS, combined with the peripheral Event System and DMA, lets sensor acquisition run deterministically without CPU intervention. The 100-pin LQFP exposes enough GPIO for color TFT displays, key matrices and isolated communication ports (RS-485, CAN). Industrial-grade -40C to +85C operation, plus 1.62 V to 3.6 V supply, fits directly into 4 mA to 20 mA loop-powered and 24 V-bus systems that use small LDO rails for the MCU.
Recommended
Smart Energy Metering
The combination of DSP extensions and a 1 MSPS ADC lets the ATSAM4S8CA-AU compute real-time power calculations (RMS, harmonic analysis) directly on-chip, eliminating a separate metering DSP. The RTC backup domain draws only 3 uA at 1.8 V, supporting battery-backed timekeeping during grid outages, while the 512 KB Flash holds metering firmware plus Tamper/PQC logs. The 100-pin LQFP footprint provides dedicated pins for tamper switches, isolated UART to the utility's communication module and an SPI interface to an external metrology AFE. These attributes make it a common choice for single-phase and three-phase smart meters.
Recommended
Motor Control and Inverters
The SAM4S has two 3-channel 16-bit timers with complementary PWM outputs, plus a dedicated PWM module that can drive 3-phase bridges directly. Combined with the Cortex-M4 DSP instructions, this allows field-oriented control (FOC) at switching frequencies above 20 kHz while leaving cycles for current-loop math and CAN diagnostics. The 100-pin LQFP exposes Hall/encoder inputs, fault inputs and shutdown pins needed for safe BLDC and PMSM drives, and the 1.62 V to 3.6 V supply supports direct 3.3 V logic interfaces to gate drivers.
Recommended
Consumer Audio and Sensor Hubs
The I2S interface and Cortex-M4 DSP extensions let the ATSAM4S8CA-AU decode compressed audio streams or run software codecs while aggregating multiple I2C/SPI sensor inputs. The 128 KB SRAM provides working space for audio buffering, and 512 KB Flash stores lightweight audio processing libraries. With USB Device support the same part doubles as the host for tethered PC applications, useful in USB headsets, smart speakers and wearable sensor hubs where BOM consolidation is critical.
Recommended
Medical Sensor and Monitoring Devices
The 12-bit ADC at 1 MSPS, combined with DSP-based filtering, supports pulse oximetry, ECG and other low-bandwidth biomedical signal chains on a single MCU. The Cortex-M4 FPU accelerates FFT-based heart-rate-variability analysis, while 128 KB SRAM holds sliding-window sample buffers without external memory. The 1.62 V to 3.6 V range and 3 uA RTC backup current suit battery-powered patient monitors that must keep time across battery swaps. Designers using the ATSAM4S8CA-AU shorten development time by re-using Microchip's validated ASF/Harmony software framework.
Recommended
Home Appliance and White Goods Control
With up to 120 MHz Cortex-M4 performance, deterministic Event System and rich timer/PWM set, the ATSAM4S8CA-AU drives washing machine, dishwasher and induction-cooktop control boards with a single chip. The 100-pin LQFP exposes enough GPIO for keypads, displays, triac control and serial interfaces to inverter modules, and 512 KB Flash holds GUI assets plus motor-control firmware. The -40C to +85C industrial range covers appliance environments, and the optional extended-grade S8CA-CU variant extends to +105C for oven-mounted controllers.
Recommended
Recommended Products Summary
Engineering reference data for ATSAM4S8CA-AU — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATSAM4S8CA-AUR | ATSAM4S16CA-AU | ATSAM4N8CA-AU | ATSAM4S4CA-CU | ATSAM4S2CA-AU |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 100-LQFP (14x14 mm) | 100-LQFP (14x14 mm) - same | 100-LQFP (14x14 mm) - same | 100-LQFP (14x14 mm) - same | 100-LQFP (14x14 mm) - same | 100-LQFP (14x14 mm) - same |
| Core / Family | Cortex-M4 SAM4S | Cortex-M4 SAM4S (same) | Cortex-M4 SAM4S (same) | Cortex-M4 SAM4N | Cortex-M4 SAM4S (same) | Cortex-M4 SAM4S (same) |
| Max Clock Speed | 120 MHz | 120 MHz | 120 MHz | 120 MHz | 120 MHz | 120 MHz |
| Flash | 512 KB | 512 KB | 1024 KB (+100%) | 512 KB | 256 KB (-50%) | 128 KB (-75%) |
| SRAM | 128 KB | 128 KB | 160 KB (+25%) | 128 KB | 48 KB (-62%) | 64 KB (-50%) |
| USB Device | Yes (FS, on-chip transceiver) | Yes (FS, on-chip) | Yes (FS, on-chip) | No | Yes (FS, on-chip) | Yes (FS, on-chip) |
| Operating Temperature | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C (CU suffix) | -40C to +85C |
| Supply Voltage | 1.62 V to 3.6 V | 1.62 V to 3.6 V | 1.62 V to 3.6 V | 1.62 V to 3.6 V | 1.62 V to 3.6 V | 1.62 V to 3.6 V |
Key Differentiators
- Highest pin count and full peripheral set in the SAM4S8 family (vs ATSAM4S8BA-MU)
- Doubles Flash headroom in the same 100-LQFP package (vs ATSAM4S4CA-CU)
- Full peripheral Event System and HS-SPI (vs ATSAM4N8CA-AU)
- Industrial temperature and on-chip USB in same package (vs ATSAM4S8CA-CU)
Design Notes
Per the Atmel-11100 SAM4S datasheet, place a 100 nF decoupling cap on each VDDCORE pin and a single 4.7 uF bulk capacitor within 5 mm of the package. VDDIO needs its own 100 nF per pin pair, and VDDOUT (the on-chip 1.8 V LDO output that feeds VDDCORE) requires at least 1 uF of output capacitance to maintain regulation under dynamic load. Failure to populate these correctly is the most common cause of POR resets during flash programming.
Keep the NRST trace short (under 25 mm) and surround it with ground guard vias; add a 10 kOhm pull-up to VDDIO and a 100 nF capacitor to ground to provide a clean POR rise. Route the USB DP/DM pair as a 90-ohm differential pair with no splits, keep it under 50 mm, and place the 22 ohm series resistors within 4 mm of the MCU pins per USB 2.0 FS layout guidelines.
Do not leave VDDBU floating even if RTC backup is unused - tie it to the same VDDIO rail through a 10 kOhm resistor and add a 100 nF bypass cap, otherwise the part can enter backup mode unexpectedly. When migrating from SAM3S or SAM7S designs, verify the peripheral Event System mapping because some SAM3S peripheral-to-pin routings changed in SAM4S, and the JTAG/SWD pinout differs on the 100-pin package.
Estimated: at 120 MHz CPU clock with all peripherals active and 3.3 V supply, core current draw is about 30 mA (200 uA/MHz dynamic, per the SAM4S datasheet), giving roughly 100 mW dissipation. The 100-pin LQFP has a theta_JA around 40 C/W on a 4-layer JEDEC test board, so junction-to-ambient rise is about 4 C - well within the 85 C industrial limit - and no explicit heatsinking is required even in enclosed enclosures.
Compliance Information
RoHS/REACH compliance and lead-free / halogen-free status confirmed on Microchip's ATSAM4S8C product page; not AEC-Q100 qualified (industrial grade only).
