STMicroelectronics Introduces STM32-F3 with FPU

STMicroelectronics has introduced its new STM32-F3 microcontrollers with an FPU.

STM32 F3 microcontrollers are system-on-chip devices based on the Cortex-M4 core with a Floating Point Unit (FPU), and are optimized for efficient handling and processing of analog signals in systems such as three-phase motor controls, biometrics and industrial sensor outputs or audio filters. The new F3 series extends the scope of ST's STM32 family by allowing designers to tackle mixed-signal control applications.

Featuring versatile analog circuitry and the ARM Cortex-M4 with FPU, the new STM32 F3 series provides low to medium memory sizes at competitive cost. The Cortex-M4 with FPU core augments the proven Cortex-M3 CPU with additional Digital Signal Processing (DSP) capabilities including single-cycle and saturating arithmetic instructions. The Floating-Point Unit (FPU) boosts performance significantly over ST's STM32 F1 Cortex-M3 devices.

The new series is positioned between the STM32-F1 and the best-in-performance-class STM32, which features the Cortex-M4 with FPU core and large memory capacity combined with high-speed 168MHz maximum CPU frequency for complex applications.

With the new F3 microcontrollers, ST's STM32 family now offers more than 350 variants addressing applications from entry-level, price-sensitive designs through to those demanding high performance and rich on-chip features. The new F3 series enables ST to deliver the advantages of its STM32 devices and ecosystem to applications that have formerly required both high-performance analog and an entry-level digital signal controller, such as high-performance motor control or embedded digital audio.

"The new F3 series boosts our ARM Cortex-M4 portfolio to more than 70 devices, and will help our customers design even more powerful products leveraging the advantages of the STM32 family," said Michel Buffa, microcontroller division general manager, STMicroelectronics. "Its advanced processor, high-quality advanced analog peripherals and mid-density memory present a strong combination unmatched by competing Cortex-based or proprietary devices."

STM32-F3 microcontrollers also incorporate ST's latest improvements to digital peripherals for its STM32 family, which Michel Buffa explains is a further advantage of the extensive compatibility between all ST's ARM Cortex-M microcontrollers.

STM32-F3 Technical Details:
The STM32 F3 microcontroller family featuring the ARM Cortex-M4 with FPU comprises four product lines, differentiated according to on-chip memory density and integrated peripherals. The peripherals provide analog function integration, including a 12-bit Analog-to-Digital Converter (ADC) with 5 Msamples/second performance.

STM32 F30x devices also have:

• Seven fast comparators with 50ns response time
• Four programmable gain amplifiers supporting four different gain settings with 1% accuracy
• Two 12-bit digital-to-analog converters (DACs),
• Four 12-bit 5Msps analog-to-digital converters (ADCs) (According to ST, this is the fastest ADC performance in any ARM Cortex-M microcontroller, with up to 18Msps in interleaved mode).
• Two advanced motor-control timers running at up to 144MHz.
  Can manage two motors plus power factor correction (PFC) with on-chip peripherals, with timing resolution faster than 7ns.

The STM32 F30x devices feature 8Kbytes of SRAM mapped to the instruction bus as Core Coupled Memory (CCM-SRAM). Critical routines loaded in the 8KB CCM at startup can be completed at full speed with zero wait states, achieving 94 Dhrystone MIPS at 72MHz. This compares with 62 DMIPS when executing from Flash or SRAM; equivalent to a 52% performance increase for critical routines. The STM32 F30x series also has up to 40Kbytes of SRAM mapped on the data bus. The 8K CCM-SRAM can also be used for data storage with no performance trade-off. Devices are pin compatible with the STM32 F1 series, and also share the same API, which simplifies migration to higher performing devices.

The STM32 F37x devices deliver a different blend of peripheral functions.  They are the first microcontrollers from ST to integrate a 16-bit Sigma-Delta ADC on-chip, allowing the STM32 family to solve a wider range of precision-sensing applications and providing a single-chip solution capable of replacing a discrete general-purpose processor and separate ADC. Up to three 16-bit Sigma-Delta ADCs are integrated on-chip, with separate analog supply from 2.2V to 3.6V, up to 21 single or 11 differential channels, and seven programmable gains per channel.

Other STM32 F37x analog peripherals include two fast comparators, three 12-bit DACs, and one 12-bit 1Msps ADC. There is also an enhanced CEC (Consumer Electronics Control) unit, making these devices ideal for consumer multimedia products. Compared to the STM32 F1 series, STM32 F37x devices provide a system-on-chip solution enabling developers to reduce bill-of-materials cost and simplify board designs.

Key common features of STM32 F30x/F37x:

• SRAM and CCM-SRAM with parity bit for secure software data and code execution;
• Memory Protection Unit (MPU);
• Capacitive touch-sense capability (24 keys);
• Support for both USB and CAN connectivity;
• Communication peripherals: SPI 18Mbps, I²C 1MHz (fast mode plus), USART 9Mbps;
• Sub-ppm trimmable RTC with HW calendar
• Four low-power modes with 5µA STOP mode having waking-up capability from communication peripherals with fast start-up time;
• 2µA standby mode with RTC running;
• below 1µA in Vbat mode (battery backup)
• Debug mode: serial wire debug (SWD), JTAG interfaces, Cortex-M4 ETM
• Power supplies: 2.0V to 3.6V or 1.8V+/-8% (dedicated sales types)

STM32-F3 Pricing:
"Pricing for the STM32 F30x series start from $2.54 for the STM32F302 with 128Kbyte Flash in LQFP48 package up to $3.86 for the 256Kbyte STM32F303 in LQFP100, for orders over 1000 pieces. The STM32 F37x starts from $2.24 for the STM32F372 in LQFP48 with 64Kbyte, up to $3.69 for the STM32F373 LQFP100 with 256Kbyte."

Both series are sampling now, to lead customers, and are scheduled to enter full production in Q3 2012.

About STMicroelectronics
STMicroelectronics is a global leader in the semiconductor market serving customers across the spectrum of sense and power technologies and multimedia convergence applications. From energy management and savings to trust and data security, from healthcare and wellness to smart consumer devices, in the home, car and office, at work and at play. In 2011, the Company's net revenues were $9.73 billion.