EFM8BB31F32A
8-bit MicrocontrollerThe EFM8BB31F32A is a 8-bit microcontroller from Silicon Labs. View the full EFM8BB31F32A datasheet below including key specifications, electrical characteristics, absolute maximum ratings.
EFM8BB31F32A shares its datasheet with EFM8BB31F32G-A-QFN32R, whose page lists every part number it covers.
Official EFM8BB31F32A datasheet (PDF) — the source this page was extracted from.
Manufacturer
Silicon LabsCategory
Microcontrollers (MCU)EFM8BB31F32A Key Specifications
| Parameter | Value |
|---|---|
| ADC | 12-bit/10-bit, up to 20 channels |
| DAC | 2 x 12-bit (on 32 kB devices) |
| RAM | 2304 bytes |
| SPI | Master/Slave, up to 12 Mbps |
| Core | Pipelined CIP-51 8051, up to 50 MHz |
| UART | 2 x UART, up to 3 Mbaud |
| Timers | 6 x 16-bit general-purpose timers, 6-channel PCA |
| I2C/SMBus | Master/Slave up to 400 kbps; High-Speed Slave up to 3.4 Mbps |
| Digital I/O | Up to 29 pins (up to 25 5V tolerant) |
| Flash Memory | 32 kB |
| Qualification | AEC-Q100 |
| Supply Voltage | 2.2V to 3.6V |
| Analog Comparators | 2 low-current with adjustable reference |
| Internal Oscillators | 49 MHz, 24.5 MHz (±2%), 80 kHz |
| Operating Temperature | -40 to 125 °C (A-grade automotive) |
EFM8BB31F32A Overview
Part: EFM8BB31F32G-A-QFN32R — Silicon Labs
Type: 8-bit Microcontroller
Description: A performance line 8-bit microcontroller with a pipelined 8051 core operating at up to 50 MHz, featuring 32 kB Flash, 2304 bytes RAM, 12-bit ADC, two 12-bit DACs, and various communication interfaces, ideal for general-purpose embedded applications.
Operating Conditions:
- Supply voltage: 2.2–3.6 V
- Operating temperature: -40 to 85 °C
- Max operating frequency: 50 MHz
Key Specs:
- Core: Pipelined 8-bit CIP-51
- Flash Memory: 32 kB (user-accessible)
- RAM: 2304 bytes (including 256 bytes 8051 RAM and 2048 bytes XRAM)
- ADC Resolution: 12-bit/10-bit
- DACs: 2 x 12-bit
- Digital I/O Pins: Up to 29 multifunction
- Internal Oscillator Accuracy: ±2% (49 MHz and 24.5 MHz)
- Max SPI Speed: 12 Mbps
Features:
- Fully compatible with standard 8051 instruction set
- In-system reprogrammable flash memory
- Internal LDO regulator, Power-on reset, and brownout detectors
- Up to 25 pins 5 V tolerant under bias
- Flexible peripheral crossbar
- Internal temperature sensor
- 2 x UART, 1 x SPI, 1 x SMBus/I2C (Master/Slave)
- I2C High-Speed Slave (up to 3.4 Mbps)
- 4 Configurable Logic Units
- 6-channel programmable counter array (PCA)
- 6 x 16-bit general-purpose timers
- Independent watchdog timer
- On-chip, non-intrusive debugging
- Pre-programmed UART bootloader
- AEC-Q100 qualified (for A-grade variants)
Applications:
- Consumer electronics
- Precision instrumentation
- Power management and control
- Industrial control and automation
- Smart sensors
- Automotive control
Package:
- QFN32-GI
- QFP32
- QFN24-GI
- QSOP24
- QFN32-AI
- QFN24-AI
EFM8BB31F32A Features
- Pipelined 8-bit 8051 MCU Core with 50 MHz operating frequency
- Up to 29 multifunction I/O pins
- One 12-bit/10-bit ADC
- Four 12-bit DACs with synchronization and PWM capabilities
- Two low-current analog comparators with built-in reference DACs
- Internal temperature sensor
- Internal 49 MHz and 24.5 MHz oscillators accurate to ±2%
- Four channels of Configurable Logic
- 6-channel PWM / PCA
- Six 16-bit general-purpose timers
- Industrial control and automation
- Smart sensors
- Automotive control
EFM8BB31F32A Electrical Characteristics
All electrical parameters in all tables are specified under the conditions listed in Table 4.1 Recommended Operating Conditions on page 19, unless stated otherwise.
EFM8BB31F32A Absolute Maximum Ratings
Stresses above those listed in Table 4.21 Absolute Maximum Ratings on page 40 may cause permanent damage to the device. This is a stress rating only and functional operation of the devices at those or any other conditions above those indicated in the operation listings of this specification is not implied. Exposure to maximum rating conditions for extended periods may affect device reliability. For more information on the available quality and reliability data, see the Quality and Reliability Monitor Report at http://www.silabs.com/ support/quality/pages/default.aspx.
Table 4.21. Absolute Maximum Ratings
| Parameter | Symbol | Test Condition | Min | Max | Unit |
|---|---|---|---|---|---|
| Ambient Temperature Under Bias | T BIAS | -55 | 125 | °C | |
| Storage Temperature | T STG | -65 | 150 | °C | |
| Voltage on VDD | V DD | GND-0.3 | 4.2 | V | |
| Voltage on VIO 2 | V IO | GND-0.3 | V DD +0.3 | V | |
| Voltage on I/O pins or RSTb, excluding P2.0-P2.3 (QFN24 and QSOP24) or P3.0-P3.3 (QFN32 and QFP32) | V IN | V IO > 3.3 V | GND-0.3 | 5.8 | V |
| Voltage on I/O pins or RSTb, excluding P2.0-P2.3 (QFN24 and QSOP24) or P3.0-P3.3 (QFN32 and QFP32) | V IN | V IO < 3.3 V | GND-0.3 | V IO +2.5 | V |
| Voltage on P2.0-P2.3 (QFN24 and QSOP24) or P3.0-P3.3 (QFN32 and QFP32) | V IN | GND-0.3 | V DD +0.3 | V | |
| Total Current Sunk into Supply Pin | I VDD | - | 200 | mA | |
| Total Current Sourced out of Ground Pin | I GND | 200 | - | mA | |
| Current Sourced or Sunk by any I/O Pin or RSTb | I IO | -100 | 100 | mA | |
| Operating Junction Temperature | T J | T A = -40 °C to 85 °C | -40 | 105 | °C |
| Operating Junction Temperature | T J | T A = -40 °C to 125 °C (I-grade or A- grade parts only) | -40 | 130 | °C |
-
Exposure to maximum rating conditions for extended periods may affect device reliability.
-
In certain package configurations, the VIO and VDD supplies are bonded to the same pin.
EFM8BB31F32A Recommended Operating Conditions
Table 4.1. Recommended Operating Conditions
| Parameter | Symbol | Test Condition | Min | Typ | Max | Unit |
|---|---|---|---|---|---|---|
| Operating Supply Voltage on VDD | V DD | 2.2 | - | 3.6 | V | |
| Operating Supply Voltage on VIO 2, | V IO | 2.2 | - | V DD | V | |
| System Clock Frequency | f SYSCLK | 0 | - | 50 | MHz | |
| Operating Ambient Temperature | T A | G-grade devices | -40 | - | 85 | °C |
| Operating Ambient Temperature | I-grade or A-grade devices | -40 | - | 125 | °C |
-
All voltages with respect to GND
-
In certain package configurations, the VIO and VDD supplies are bonded to the same pin.
-
I/O have reduced current drive/sink capabilities at lower VIO levels. See 4.1.16 Port I/O for additional information.
EFM8BB31F32A Package Information
Figure 7.1. Package Drawing
Table 7.1. Package Dimensions
| Dimension | Min | Typ | Max |
|---|---|---|---|
| A | 0.45 | 0.50 | 0.55 |
| A1 | 0.00 | 0.035 | 0.05 |
| b | 0.15 | 0.20 | 0.25 |
| D | 4.00 BSC. | 4.00 BSC. | 4.00 BSC. |
| D2 | 2.80 | 2.90 | 3.00 |
| e | 0.40 BSC. | 0.40 BSC. | 0.40 BSC. |
| E | 4.00 BSC. | 4.00 BSC. | 4.00 BSC. |
| E2 | 2.80 | 2.90 | 3.00 |
| L | 0.20 | 0.30 | 0.40 |
| aaa | - | - | 0.10 |
| bbb | - | - | 0.10 |
| ccc | - | - | 0.08 |
| ddd | - | - | 0.10 |
| eee | - | - | 0.10 |
| ggg | - | - | 0.05 |
- All dimensions shown are in millimeters (mm) unless otherwise noted.
- Dimensioning and Tolerancing per ANSI Y14.5M-1994.
- This drawing conforms to JEDEC Solid State Outline MO-220.
- Recommended card reflow profile is per the JEDEC/IPC J-STD-020C specification for Small Body Components.
Min
Typ
Max
Variants on the same datasheet
These parts have exact links to the same datasheet. They are candidates to compare, not verified drop-in replacements; check package, pinout and electrical limits.
| Part Number | Manufacturer | Package |
|---|---|---|
| EFM8BB3 | Silicon Labs | — |
| EFM8BB31F16A | Silicon Labs | — |
| EFM8BB31F16G | Silicon Labs | — |
| EFM8BB31F16I | Silicon Labs | — |
| EFM8BB31F32G | Silicon Labs | — |
| EFM8BB31F32G-A-QFN32R | Silicon Labs | QFN-32 5x5mm |
| EFM8BB31F32G-D | Silicon Labs | — |
| EFM8BB31F32G-D-QFN24 | Silicon Labs | QFN-24 3x3mm |
| EFM8BB31F32G-D-QFN32 | Silicon Labs | QFN-32 4x4mm |
| EFM8BB31F32G-D-QFP32 | Silicon Labs | QFP-32 |
| EFM8BB31F32I | Silicon Labs | — |
| EFM8BB31F64A | Silicon Labs | QFN-32 5x5mm |
| EFM8BB31F64G | Silicon Labs | — |
| EFM8BB31F64I | Silicon Labs | — |
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All Microcontrollers (MCU) datasheetsAll Silicon Labs datasheets (179)
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