EFM8 Universal Bee Family
EFM8UB1 Data Sheet
The EFM8UB1, part of the Universal Bee family of MCUs, is a
multi-purpose line of 8-bit microcontrollers with USB feature set in
small packages.
KEY FEATURES
• Pipelined 8-bit C8051 core with 50 MHz
maximum operating frequency
These devices offer high value by integrating an innovative energy-smart USB peripheral
interface, charger detect circuit, 8 kV ESD protection, and enhanced high speed communication interfaces into small packages, making them ideal for space-constrained USB
applications. With an efficient 8051 core and precision analog, the EFM8UB1 family is
also optimal for embedded applications.
• Up to 22 multifunction, 5 V tolerant I/O
pins
• Low Energy USB with full- and low-speed
support saves up to 90% of the USB
energy
• USB charger detect circuit (USB-BCS 1.2
compliant)
EFM8UB1 applications include the following:
• Consumer electronics
• Medical equipment
• USB I/O controls, dongles
• High-speed communication bridge
• One 12-bit ADC and two analog
comparators with internal voltage DAC as
reference input
• Five 16-bit timers
• Two UARTs, SPI, SMBus/I2C master/
slave and I2C slave
• Priority crossbar for flexible pin mapping
Core / Memory
Clock Management
CIP-51 8051 Core
(50 MHz)
Flash Program
Memory
RAM Memory
(2304 bytes)
(up to 16 KB)
Debug Interface
with C2
Energy Management
External CMOS
Oscillator
High Frequency
48 MHz RC
Oscillator
Internal LDO
Regulator
Power-On Reset
Low Frequency
RC Oscillator
High Frequency
24.5 MHz RC
Oscillator
Brown-Out
Detector
5 V-to 3.3 V LDO
Regulator
8-bit SFR bus
Serial Interfaces
2 x UART
SPI
I2C / SMBus
USB
High-Speed I2C Slave
I/O Ports
Timers and Triggers
Analog Interfaces
External
Interrupts
Pin Reset
Timer
0/1/2
PCA/PWM
ADC
Comparator 0
General
Purpose I/O
Pin Wakeup
Watchdog
Timer
Timer 3/4
Comparator 1
Internal
Voltage
Reference
Security
16-bit CRC
Lowest power mode with peripheral operational:
Normal
Idle
Suspend
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Snooze
Shutdown
Rev. 1.3
EFM8UB1 Data Sheet
Feature List
1. Feature List
The EFM8UB1 highlighted features are listed below.
• Core
• Pipelined CIP-51 Core
• Fully compatible with standard 8051 instruction set
• 70% of instructions execute in 1-2 clock cycles
• 50 MHz maximum operating frequency
• Memory
• Up to 16 KB flash memory, in-system re-programmable
from firmware, including 1 KB of 64-byte sectors and 15
KB of 512-byte sectors.
• Up to 2304 bytes RAM (including 256 bytes standard 8051
RAM, 1024 bytes on-chip XRAM, and 1024 bytes of USB
buffer)
• Power
• 5 V-input LDO regulator for direct connection to USB supply
• Internal LDO regulator for CPU core voltage
• Power-on reset circuit and brownout detectors
• I/O: Up to 22 total multifunction I/O pins
• All pins 5 V tolerant under bias
• Flexible peripheral crossbar for peripheral routing
• 5 mA source, 12.5 mA sink allows direct drive of LEDs
• Clock Sources
• Internal 48 MHz oscillator with accuracy of ±1.5% standalone and ±0.25% using USB clock recovery
• Internal 24.5 MHz oscillator with ±2% accuracy
• Internal 80 kHz low-frequency oscillator
• External CMOS clock option
• Timers/Counters and PWM
• 3-channel Programmable Counter Array (PCA) supporting
PWM, capture/compare, and frequency output modes
• 5 x 16-bit general-purpose timers
• Independent watchdog timer, clocked from the low frequency oscillator
• Communications and Digital Peripherals
• USB 2.0-compliant full speed with integrated low-power
transceiver, 4 bidirectional endpoints, and dedicated 1 KB
buffer
• 2 x UART, up to 3 Mbaud
• SPI™ Master / Slave, up to 12 Mbps
• SMBus™/I2C™ Master / Slave, up to 400 kbps
• I2C High-Speed Slave, up to 3.4 Mbps
•
•
•
•
•
•
• 16-bit CRC unit, supporting automatic CRC of flash at 256byte boundaries
Analog
• 12-Bit Analog-to-Digital Converter (ADC)
• 2 x Low-current analog comparators with adjustable reference
On-Chip, Non-Intrusive Debugging
• Full memory and register inspection
• Four hardware breakpoints, single-stepping
Pre-loaded USB bootloader
Temperature range -40 to 85 ºC
Single power supply of 2.2 to 3.6 V or 3.0 to 5.25 V
QSOP24, QFN28, and QFN20 packages
With on-chip power-on reset, voltage supply monitor, watchdog timer, and clock oscillator, the EFM8UB1 devices are truly standalone
system-on-a-chip solutions. The flash memory is reprogrammable in-circuit, providing nonvolatile data storage and allowing field upgrades of the firmware. The on-chip debugging interface (C2) allows non-intrusive (uses no on-chip resources), full speed, in-circuit
debugging using the production MCU installed in the final application. This debug logic supports inspection and modification of memory
and registers, setting breakpoints, single stepping, and run and halt commands. All analog and digital peripherals are fully functional
while debugging. The on-chip 5V-to-3.3V regulator enables operation from 2.2 V up to a 5.25 V supply. Devices are available in 28-pin
QFN, 20-pin QFN, or 24-pin QSOP packages. All package options are lead-free and RoHS compliant.
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Rev. 1.3 | 2
EFM8UB1 Data Sheet
Ordering Information
2. Ordering Information
EFM8 UB1 0 F 16 G – A – QFN28 R
Tape and Reel (Optional)
Package Type
Revision
Temperature Grade G (-40 to +85)
Flash Memory Size – 16 KB
Memory Type (Flash)
Family Feature Set
Universal Bee 1 Family
Silicon Labs EFM8 Product Line
Figure 2.1. EFM8UB1 Part Numbering
All EFM8UB1 family members have the following features:
• CIP-51 Core running up to 50 MHz
• Three Internal Oscillators (48 MHz, 24.5 MHz and 80 kHz)
• USB Full/Low speed Function Controller
• SMBus
• I2C Slave
• SPI
• 2 UARTs
• 3-Channel Programmable Counter Array (PWM, Clock Generation, Capture/Compare)
• 5 16-bit Timers
• 2 Analog Comparators
• 12-bit Analog-to-Digital Converter with integrated multiplexer, voltage reference, and temperature sensor
• 16-bit CRC Unit
• Pre-loaded USB bootloader
In addition to these features, each part number in the EFM8UB1 family has a set of features that vary across the product line. The
product selection guide shows the features available on each family member.
Temperature Range
Package
Yes
—
-40 to +85 °C
QFN28
EFM8UB11F16G-C-QSOP24
16
2304
17
15
8
9
Yes
Yes
-40 to +85 °C
QSOP24
EFM8UB10F16G-C-QFN20
16
2304
13
11
8
5
Yes
—
-40 to +85 °C
QFN20
EFM8UB10F8G-C-QFN20
8
2304
13
11
8
5
Yes
—
-40 to +85 °C
QFN20
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and VDD Pins
12
Separate VIO
Comparator 1 Inputs
10
(RoHS Compliant)
Comparator 0 Inputs
20
Pb-free
ADC0 Channels
22
I/Os (Total)
2304
Digital Port
RAM (Bytes)
16
Part Number
EFM8UB10F16G-C-QFN28
Ordering
Flash Memory (kB)
Table 2.1. Product Selection Guide
Rev. 1.3 | 3
Table of Contents
1. Feature List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Ordering Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. System Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
3.1 Introduction.
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3.2 Power
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3.3 I/O.
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3.4 Clocking .
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3.5 Counters/Timers and PWM .
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3.6 Communications and Other Digital Peripherals .
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3.7 Analog .
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3.8 Reset Sources
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.13
3.9 Debugging .
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.13
3.10 Bootloader
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.14
4. Electrical Specifications
. . . . . . . . . . . . . . . . . . . . . . . . . . 16
4.1 Electrical Characteristics . . . . . . .
4.1.1 Recommended Operating Conditions .
4.1.2 Power Consumption. . . . . . .
4.1.3 Reset and Supply Monitor . . . . .
4.1.4 Flash Memory . . . . . . . . .
4.1.5 Power Management Timing . . . .
4.1.6 Internal Oscillators . . . . . . .
4.1.7 External Clock Input . . . . . . .
4.1.8 ADC . . . . . . . . . . . .
4.1.9 Voltage Reference . . . . . . .
4.1.10 Temperature Sensor . . . . . .
4.1.11 1.8 V Internal LDO Voltage Regulator
4.1.12 5 V Voltage Regulator. . . . . .
4.1.13 Comparators . . . . . . . . .
4.1.14 Port I/O . . . . . . . . . .
4.1.15 USB Transceiver . . . . . . .
4.1.16 SMBus . . . . . . . . . . .
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.16
.16
.17
.19
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.21
.22
.23
.24
.24
.24
.25
.26
.27
.28
4.2 Thermal Conditions .
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4.3 Absolute Maximum Ratings .
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.30
4.4 Typical Performance Curves .
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.31
5. Typical Connection Diagrams
. . . . . . . . . . . . . . . . . . . . . . . . 35
5.1 Power
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.35
5.2 USB .
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.37
5.3 Debug
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.39
5.4 Other Connections .
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.39
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Rev. 1.3 | 4
6. Pin Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
6.1 EFM8UB1x-QFN28 Pin Definitions .
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.40
6.2 EFM8UB1x-QSOP24 Pin Definitions .
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.44
6.3 EFM8UB1x-QFN20 Pin Definitions .
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.47
7. QFN28 Package Specifications. . . . . . . . . . . . . . . . . . . . . . . .
50
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7.1 QFN28 Package Dimensions
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.50
7.2 QFN28 PCB Land Pattern
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.52
7.3 QFN28 Package Marking .
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.53
8. QSOP24 Package Specifications . . . . . . . . . . . . . . . . . . . . . . . 54
8.1 Package Dimensions
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.54
8.2 PCB Land Pattern
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.56
8.3 Package Marking .
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.57
9. QFN20 Package Specifications. . . . . . . . . . . . . . . . . . . . . . . .
58
9.1 QFN20 Package Dimensions
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.58
9.2 QFN20 PCB Land Pattern
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.60
9.3 QFN20 Package Marking .
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.61
10. Revision History. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
62
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Rev. 1.3 | 5
EFM8UB1 Data Sheet
System Overview
3. System Overview
3.1 Introduction
C2CK/RSTb
CIP-51 8051 Controller
Core
Digital Peripherals
16 KB ISP Flash
Program Memory
Reset
UART0
UART1
Power-On
Reset
Timers 0,
1, 2, 3, 4
256 Byte SRAM
Supply
Monitor
Independent
Watchdog
Timer
I2C Slave
VDD
VREGIN
Power
Net
Voltage
Regulators
CRC
SFR
Bus
Crossbar Control
CMOS Oscillator
Input
Analog Peripherals
Port 1
Drivers
P1.n
Port 2
Drivers
P2.n
Port 3
Drivers
P3.n
Internal
Reference
48 MHz 1.5%
Oscillator
Clock
Recovery
P0.n
SPI
System Clock
Configuration
24.5 MHz 2%
Oscillator
VDD
VREF
VDD
GND
USB Peripheral
D+
DVBUS
I2C /
SMBus
SYSCLK
Port 0
Drivers
Priority
Crossbar
Decoder
3-ch PCA
1024 Byte XRAM
Low Freq.
Oscillator
EXTCLK
Port I/O Configuration
Full / Low
Speed
Transceiver
1 KB RAM
12/10 bit
ADC
AMUX
Debug /
C2D
Programming
Hardware
Controller
Charge
Detection
Low Power
Temp
Sensor
+
-+
2 Comparators
Figure 3.1. Detailed EFM8UB1 Block Diagram
This section describes the EFM8UB1 family at a high level.
For more information on the device packages and pinout, electrical specifications, and typical connection diagrams, see the EFM8UB1
Data Sheet. For more information on each module including register definitions, see the EFM8UB1 Reference Manual. For more information on any errata, see the EFM8UB1 Errata.
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Rev. 1.3 | 6
EFM8UB1 Data Sheet
System Overview
3.2 Power
All internal circuitry draws power from the VDD supply pin. External I/O pins are powered from the VIO supply voltage (or VDD on devices without a separate VIO connection), while most of the internal circuitry is supplied by an on-chip LDO regulator. Control over the
device power can be achieved by enabling/disabling individual peripherals as needed. Each analog peripheral can be disabled when
not in use and placed in low power mode. Digital peripherals, such as timers and serial buses, have their clocks gated off and draw little
power when they are not in use.
Table 3.1. Power Modes
Power Mode
Details
Mode Entry
Wake-Up Sources
Normal
Core and all peripherals clocked and fully operational
—
—
Set IDLE bit in PCON0
Any interrupt
Idle
• Core halted
• All peripherals clocked and fully operational
• Code resumes execution on wake event
Suspend
•
•
•
•
•
Core and peripheral clocks halted
HFOSC0 and HFOSC1 oscillators stopped
Regulators in normal bias mode for fast wake
Timer 3 and 4 may clock from LFOSC0
Code resumes execution on wake event
1. Switch SYSCLK to
HFOSC0
2. Set SUSPEND bit in
PCON1
Stop
•
•
•
•
•
All internal power nets shut down
5V regulator remains active (if enabled)
Internal 1.8 V LDO on
Pins retain state
Exit on any reset source
1. Clear STOPCF bit in
REG0CN
2. Set STOP bit in
PCON0
Snooze
• Core and peripheral clocks halted
• HFOSC0 and HFOSC1 oscillators stopped
• Regulators in low bias current mode for energy savings
• Timer 3 and 4 may clock from LFOSC0
• Code resumes execution on wake event
1. Switch SYSCLK to
HFOSC0
2. Set SNOOZE bit in
PCON1
•
•
•
•
•
•
Shutdown
•
•
•
•
•
1. Set STOPCF bit in
REG0CN
2. Set STOP bit in
PCON0
• RSTb pin reset
• Power-on reset
All internal power nets shut down
5V regulator remains active (if enabled)
Internal 1.8 V LDO off to save energy
Pins retain state
Exit on pin or power-on reset
•
•
•
•
•
•
USB0 Bus Activity
Timer 4 Event
SPI0 Activity
I2C0 Slave Activity
Port Match Event
Comparator 0 Falling
Edge
Any reset source
USB0 Bus Activity
Timer 4 Event
SPI0 Activity
I2C0 Slave Activity
Port Match Event
Comparator 0 Falling
Edge
3.3 I/O
Digital and analog resources are externally available on the device’s multi-purpose I/O pins. Port pins P0.0-P2.3 can be defined as general-purpose I/O (GPIO), assigned to one of the internal digital resources through the crossbar or dedicated channels, or assigned to an
analog function. Port pins P3.0 and P3.1 can be used as GPIO. Additionally, the C2 Interface Data signal (C2D) is shared with P3.0.
The port control block offers the following features:
• Up to 22 multi-functions I/O pins, supporting digital and analog functions.
• Flexible priority crossbar decoder for digital peripheral assignment.
• Two drive strength settings for each port.
• Two direct-pin interrupt sources with dedicated interrupt vectors (INT0 and INT1).
• Up to 20 direct-pin interrupt sources with shared interrupt vector (Port Match).
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Rev. 1.3 | 7
EFM8UB1 Data Sheet
System Overview
3.4 Clocking
The CPU core and peripheral subsystem may be clocked by both internal and external oscillator resources. By default, the system
clock comes up running from the 24.5 MHz oscillator divided by 8.
The clock control system offers the following features:
• Provides clock to core and peripherals.
• 24.5 MHz internal oscillator (HFOSC0), accurate to ±2% over supply and temperature corners.
• 48 MHz internal oscillator (HFOSC1), accurate to ±1.5% over supply and temperature corners.
• 80 kHz low-frequency oscillator (LFOSC0).
• External CMOS clock input (EXTCLK).
• Clock divider with eight settings for flexible clock scaling:
• Divide the selected clock source by 1, 2, 4, 8, 16, 32, 64, or 128.
• HFOSC0 and HFOSC1 include 1.5x pre-scalers for further flexibility.
3.5 Counters/Timers and PWM
Programmable Counter Array (PCA0)
The programmable counter array (PCA) provides multiple channels of enhanced timer and PWM functionality while requiring less CPU
intervention than standard counter/timers. The PCA consists of a dedicated 16-bit counter/timer and one 16-bit capture/compare module for each channel. The counter/timer is driven by a programmable timebase that has flexible external and internal clocking options.
Each capture/compare module may be configured to operate independently in one of five modes: Edge-Triggered Capture, Software
Timer, High-Speed Output, Frequency Output, or Pulse-Width Modulated (PWM) Output. Each capture/compare module has its own
associated I/O line (CEXn) which is routed through the crossbar to port I/O when enabled.
•
•
•
•
•
•
•
•
•
•
16-bit time base
Programmable clock divisor and clock source selection
Up to three independently-configurable channels
8, 9, 10, 11 and 16-bit PWM modes (center or edge-aligned operation)
Output polarity control
Frequency output mode
Capture on rising, falling or any edge
Compare function for arbitrary waveform generation
Software timer (internal compare) mode
Can accept hardware “kill” signal from comparator 0
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Rev. 1.3 | 8
EFM8UB1 Data Sheet
System Overview
Timers (Timer 0, Timer 1, Timer 2, Timer 3, and Timer 4)
Several counter/timers are included in the device: two are 16-bit counter/timers compatible with those found in the standard 8051, and
the rest are 16-bit auto-reload timers for timing peripherals or for general purpose use. These timers can be used to measure time intervals, count external events and generate periodic interrupt requests. Timer 0 and Timer 1 are nearly identical and have four primary
modes of operation. The other timers offer both 16-bit and split 8-bit timer functionality with auto-reload and capture capabilities.
Timer 0 and Timer 1 include the following features:
• Standard 8051 timers, supporting backwards-compatibility with firmware and hardware.
• Clock sources include SYSCLK, SYSCLK divided by 12, 4, or 48, the External Clock divided by 8, or an external pin.
• 8-bit auto-reload counter/timer mode
• 13-bit counter/timer mode
• 16-bit counter/timer mode
• Dual 8-bit counter/timer mode (Timer 0)
Timer 2, Timer 3 and Timer 4 are 16-bit timers including the following features:
• Clock sources for all timers include SYSCLK, SYSCLK divided by 12, or the External Clock divided by 8.
• LFOSC0 divided by 8 may be used to clock Timer 3 and Timer 4 in active or suspend/snooze power modes.
• Timer 4 is a low-power wake source, and can be chained together with Timer 3.
• 16-bit auto-reload timer mode.
• Dual 8-bit auto-reload timer mode.
• External pin capture.
• LFOSC0 capture.
• Comparator 0 capture.
• USB Start-of-Frame (SOF) capture.
Watchdog Timer (WDT0)
The device includes a programmable watchdog timer (WDT) running off the low-frequency oscillator. A WDT overflow forces the MCU
into the reset state. To prevent the reset, the WDT must be restarted by application software before overflow. If the system experiences
a software or hardware malfunction preventing the software from restarting the WDT, the WDT overflows and causes a reset. Following
a reset, the WDT is automatically enabled and running with the default maximum time interval. If needed, the WDT can be disabled by
system software or locked on to prevent accidental disabling. Once locked, the WDT cannot be disabled until the next system reset.
The state of the RST pin is unaffected by this reset.
The Watchdog Timer has the following features:
• Programmable timeout interval
• Runs from the low-frequency oscillator
• Lock-out feature to prevent any modification until a system reset
3.6 Communications and Other Digital Peripherals
Universal Serial Bus (USB0)
The USB0 peripheral provides a full-speed USB 2.0 compliant device controller and PHY with additional Low Energy USB features. The
device supports both full-speed (12MBit/s) and low speed (1.5MBit/s) operation, and includes a dedicated USB oscillator with clock recovery mechanism for crystal-free operation. No external components are required. The USB function controller (USB0) consists of a
Serial Interface Engine (SIE), USB transceiver (including matching resistors and configurable pull-up resistors), and 1 KB FIFO block.
The Low Energy Mode ensures the current consumption is optimized and enables USB communication on a strict power budget.
The USB0 module includes the following features:
• Full and Low Speed functionality.
• Implements 4 bidirectional endpoints.
• Low Energy Mode to reduce active supply current based on bus bandwidth.
• USB 2.0 compliant USB peripheral support (no host capability).
• Direct module access to 1 KB of RAM for FIFO memory.
• Clock recovery to meet USB clocking requirements with no external components.
• Charger detection circuitry with automatic detection of SDP, CDP, and DCP interfaces.
• D+ and D- can be routed to ADC input to support ACM and proprietary charger architectures.
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Rev. 1.3 | 9
EFM8UB1 Data Sheet
System Overview
Universal Asynchronous Receiver/Transmitter (UART0)
UART0 is an asynchronous, full duplex serial port offering modes 1 and 3 of the standard 8051 UART. Enhanced baud rate support
allows a wide range of clock sources to generate standard baud rates. Received data buffering allows UART0 to start reception of a
second incoming data byte before software has finished reading the previous data byte.
The UART module provides the following features:
• Asynchronous transmissions and receptions.
• Baud rates up to SYSCLK/2 (transmit) or SYSCLK/8 (receive).
• 8- or 9-bit data.
• Automatic start and stop generation.
• Single-byte FIFO on transmit and receive.
Universal Asynchronous Receiver/Transmitter (UART1)
UART1 is an asynchronous, full duplex serial port offering a variety of data formatting options. A dedicated baud rate generator with a
16-bit timer and selectable prescaler is included, which can generate a wide range of baud rates. A received data FIFO allows UART1
to receive multiple bytes before data is lost and an overflow occurs.
UART1 provides the following features:
• Asynchronous transmissions and receptions.
• Dedicated baud rate generator supports baud rates up to SYSCLK/2 (transmit) or SYSCLK/8 (receive).
• 5, 6, 7, 8, or 9 bit data.
• Automatic start and stop generation.
• Automatic parity generation and checking.
• Four byte FIFO on transmit and receive.
• Auto-baud detection.
• LIN break and sync field detection.
• CTS / RTS hardware flow control.
Serial Peripheral Interface (SPI0)
The serial peripheral interface (SPI) module provides access to a flexible, full-duplex synchronous serial bus. The SPI can operate as a
master or slave device in both 3-wire or 4-wire modes, and supports multiple masters and slaves on a single SPI bus. The slave-select
(NSS) signal can be configured as an input to select the SPI in slave mode, or to disable master mode operation in a multi-master
environment, avoiding contention on the SPI bus when more than one master attempts simultaneous data transfers. NSS can also be
configured as a firmware-controlled chip-select output in master mode, or disabled to reduce the number of pins required. Additional
general purpose port I/O pins can be used to select multiple slave devices in master mode.
•
•
•
•
•
•
•
•
Supports 3- or 4-wire master or slave modes.
Supports external clock frequencies up to 12 Mbps in master or slave mode.
Support for all clock phase and polarity modes.
8-bit programmable clock rate (master).
Programmable receive timeout (slave).
Four byte FIFO on transmit and receive.
Can operate in suspend or snooze modes and wake the CPU on reception of a byte.
Support for multiple masters on the same data lines.
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EFM8UB1 Data Sheet
System Overview
System Management Bus / I2C (SMB0)
The SMBus I/O interface is a two-wire, bi-directional serial bus. The SMBus is compliant with the System Management Bus Specification, version 1.1, and compatible with the I2C serial bus.
The SMBus module includes the following features:
• Standard (up to 100 kbps) and Fast (400 kbps) transfer speeds
• Support for master, slave, and multi-master modes
• Hardware synchronization and arbitration for multi-master mode
• Clock low extending (clock stretching) to interface with faster masters
• Hardware support for 7-bit slave and general call address recognition
• Firmware support for 10-bit slave address decoding
• Ability to inhibit all slave states
• Programmable data setup/hold times
• Transmit and receive FIFOs (one byte) to help increase throughput in faster applications
I2C Slave (I2CSLAVE0)
The I2C Slave interface is a 2-wire, bidirectional serial bus that is compatible with the I2C Bus Specification 3.0. It is capable of transferring in high-speed mode (HS-mode) at speeds of up to 3.4 Mbps. Firmware can write to the I2C interface, and the I2C interface can
autonomously control the serial transfer of data. The interface also supports clock stretching for cases where the core may be temporarily prohibited from transmitting a byte or processing a received byte during an I2C transaction. This module operates only as an I2C
slave device.
The I2C module includes the following features:
• Standard (up to 100 kbps), Fast (400 kbps), Fast Plus (1 Mbps), and High-speed (3.4 Mbps) transfer speeds
• Support for slave mode only
• Clock low extending (clock stretching) to interface with faster masters
• Hardware support for 7-bit slave address recognition
• Transmit and receive FIFOs (two bytes) to help increase throughput in faster applications
16-bit CRC (CRC0)
The cyclic redundancy check (CRC) module performs a CRC using a 16-bit polynomial. CRC0 accepts a stream of 8-bit data and posts
the 16-bit result to an internal register. In addition to using the CRC block for data manipulation, hardware can automatically CRC the
flash contents of the device.
The CRC module is designed to provide hardware calculations for flash memory verification and communications protocols. The CRC
module supports the standard CCITT-16 16-bit polynomial (0x1021), and includes the following features:
• Support for CCITT-16 polynomial
• Byte-level bit reversal
• Automatic CRC of flash contents on one or more 256-byte blocks
• Initial seed selection of 0x0000 or 0xFFFF
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Rev. 1.3 | 11
EFM8UB1 Data Sheet
System Overview
3.7 Analog
12-Bit Analog-to-Digital Converter (ADC0)
The ADC is a successive-approximation-register (SAR) ADC with 12-, 10-, and 8-bit modes, integrated track-and hold and a programmable window detector. The ADC is fully configurable under software control via several registers. The ADC may be configured to
measure different signals using the analog multiplexer. The voltage reference for the ADC is selectable between internal and external
reference sources.
•
•
•
•
•
•
•
•
•
•
•
Up to 20 external inputs.
Single-ended 12-bit and 10-bit modes.
Supports an output update rate of 200 ksps samples per second in 12-bit mode or 800 ksps samples per second in 10-bit mode.
Operation in low power modes at lower conversion speeds.
Asynchronous hardware conversion trigger, selectable between software, external I/O and internal timer sources.
Output data window comparator allows automatic range checking.
Support for burst mode, which produces one set of accumulated data per conversion-start trigger with programmable power-on settling and tracking time.
Conversion complete and window compare interrupts supported.
Flexible output data formatting.
Includes an internal fast-settling reference with two levels (1.65 V and 2.4 V) and support for external reference and signal ground.
Integrated temperature sensor.
Low Current Comparators (CMP0, CMP1)
Analog comparators are used to compare the voltage of two analog inputs, with a digital output indicating which input voltage is higher.
External input connections to device I/O pins and internal connections are available through separate multiplexers on the positive and
negative inputs. Hysteresis, response time, and current consumption may be programmed to suit the specific needs of the application.
The comparator includes the following features:
• Up to 10 (CMP0) or 12 (CMP1) external positive inputs
• Up to 10 (CMP0) or 12 (CMP1) external negative inputs
• Additional input options:
• Internal connection to LDO output
• Direct connection to GND
• Direct connection to VDD
• Dedicated 6-bit reference DAC
• Synchronous and asynchronous outputs can be routed to pins via crossbar
• Programmable hysteresis between 0 and ±20 mV
• Programmable response time
• Interrupts generated on rising, falling, or both edges
• PWM output kill feature
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Rev. 1.3 | 12
EFM8UB1 Data Sheet
System Overview
3.8 Reset Sources
Reset circuitry allows the controller to be easily placed in a predefined default condition. On entry to this reset state, the following occur:
• The core halts program execution.
• Module registers are initialized to their defined reset values unless the bits reset only with a power-on reset.
• External port pins are forced to a known state.
• Interrupts and timers are disabled.
All registers are reset to the predefined values noted in the register descriptions unless the bits only reset with a power-on reset. The
contents of RAM are unaffected during a reset; any previously stored data is preserved as long as power is not lost. The Port I/O latches are reset to 1 in open-drain mode. Weak pullups are enabled during and after the reset. For Supply Monitor and power-on resets,
the RSTb pin is driven low until the device exits the reset state. On exit from the reset state, the program counter (PC) is reset, and the
system clock defaults to an internal oscillator. The Watchdog Timer is enabled, and program execution begins at location 0x0000.
Reset sources on the device include:
• Power-on reset
• External reset pin
• Comparator reset
• Software-triggered reset
• Supply monitor reset (monitors VDD supply)
• Watchdog timer reset
• Missing clock detector reset
• Flash error reset
• USB reset
3.9 Debugging
The EFM8UB1 devices include an on-chip Silicon Labs 2-Wire (C2) debug interface to allow flash programming and in-system debugging with the production part installed in the end application. The C2 interface uses a clock signal (C2CK) and a bi-directional C2 data
signal (C2D) to transfer information between the device and a host system. See the C2 Interface Specification for details on the C2
protocol.
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Rev. 1.3 | 13
EFM8UB1 Data Sheet
System Overview
3.10 Bootloader
All devices come pre-programmed with a USB bootloader. This bootloader resides in the code security page and last pages of code
flash; it can be erased if it is not needed.
The byte before the Lock Byte is the Bootloader Signature Byte. Setting this byte to a value of 0xA5 indicates the presence of the bootloader in the system. Any other value in this location indicates that the bootloader is not present in flash.
When a bootloader is present, the device will jump to the bootloader vector after any reset, allowing the bootloader to run. The bootloader then determines if the device should stay in bootload mode or jump to the reset vector located at 0x0000. When the bootloader
is not present, the device will jump to the reset vector of 0x0000 after any reset.
More information about the bootloader protocol and usage can be found in AN945: EFM8 Factory Bootloader User Guide. Application
notes can be found on the Silicon Labs website (www.silabs.com/8bit-appnotes) or within Simplicity Studio by using the [Application
Notes] tile.
0xFFC0
0xFFBF
0xFC00
Read-Only
Reserved
0xFBFF
Lock Byte
0xFBFE
Bootloader Signature Byte
Code Security Page
0xF800
0xF7FF
0x4000
0x3FFF
64 Bytes
Bootloader Vector
Nonvolatile Data
Reserved
Bootloader
0xFBC0
0xFBBF
Bootloader
0xFFFF
16 KB Code
(32 x 512 Byte pages)
0x0000
Reset Vector
Figure 3.2. Flash Memory Map with Bootloader—16 KB Devices
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Rev. 1.3 | 14
EFM8UB1 Data Sheet
System Overview
Table 3.2. Summary of Pins for Bootloader Communication
Bootloader
Pins for Bootload Communication
UART
TX – P0.4
RX – P0.5
USB
VBUS
D+
D-
Table 3.3. Summary of Pins for Bootload Mode Entry
Device Package
Pin for Bootload Mode Entry
QFN28
P3.0 / C2D
QSOP24
P2.0 / C2D
QFN20
P2.0 / C2D
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Rev. 1.3 | 15
EFM8UB1 Data Sheet
Electrical Specifications
4. Electrical Specifications
4.1 Electrical Characteristics
All electrical parameters in all tables are specified under the conditions listed in Table 4.1 Recommended Operating Conditions on page
16, unless stated otherwise.
4.1.1 Recommended Operating Conditions
Table 4.1. Recommended Operating Conditions
Parameter
Min
Typ
Max
Unit
2.2
—
3.6
V
Operating Supply Voltage on VIO 3 VIO
1.71
—
VDD
V
Operating Supply Voltage on VRE- VREGIN
GIN
3.0
—
5.25
V
0
—
50
MHz
-40
—
85
°C
Operating Supply Voltage on VDD
Symbol
Test Condition
VDD
1
System Clock Frequency
fSYSCLK
Operating Ambient Temperature
TA
Note:
1. Standard USB compliance tests require a minimum of 3.0 V on VDD for compliant operation.
2. All voltages with respect to GND.
3. On devices without a VIO pin, VIO = VDD.
4. GPIO levels are undefined whenever VIO is less than 1 V.
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Rev. 1.3 | 16
EFM8UB1 Data Sheet
Electrical Specifications
4.1.2 Power Consumption
Table 4.2. Power Consumption
Parameter
Symbol
Test Condition
Min
Typ
Max
Unit
FSYSCLK = 48 MHz (HFOSC1) 2
—
9.4
10.1
mA
FSYSCLK = 24.5 MHz (HFOSC0) 2
—
4.5
5.2
mA
FSYSCLK = 1.53 MHz (HFOSC0) 2
—
600
—
μA
FSYSCLK = 80 kHz 3
—
145
—
μA
FSYSCLK = 48 MHz (HFOSC1) 2
—
6.3
6.8
mA
FSYSCLK = 24.5 MHz (HFOSC0) 2
—
2.9
3.3
mA
FSYSCLK = 1.53 MHz (HFOSC0) 2
—
440
—
μA
FSYSCLK = 80 kHz 3
—
130
—
μA
LFO Running
—
125
—
μA
LFO Stopped
—
120
—
μA
LFO Running
—
25
—
μA
LFO Stopped
—
20
—
μA
Digital Core Supply Current
Normal Mode-Full speed with code IDD
executing from flash
Idle Mode-Core halted with peripherals running
IDD
Suspend Mode-Core halted and
high frequency clocks stopped,
Supply monitor off.
IDD
Snooze Mode-Core halted and
high frequency clocks stopped.
Regulator in low-power state, Supply monitor off.
IDD
Stop Mode—Core halted and all
clocks stopped,Internal LDO On,
Supply monitor off.
IDD
—
120
—
μA
Shutdown Mode—Core halted and
all clocks stopped,Internal LDO
Off, Supply monitor off.
IDD
—
0.2
—
μA
—
105
—
μA
—
850
—
μA
—
4
—
μA
Analog Peripheral Supply Currents
High-Frequency Oscillator 0
IHFOSC0
Operating at 24.5 MHz,
TA = 25 °C
High-Frequency Oscillator 1
IHFOSC1
Operating at 48 MHz,
TA = 25 °C
Low-Frequency Oscillator
ILFOSC
Operating at 80 kHz,
TA = 25 °C
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Rev. 1.3 | 17
EFM8UB1 Data Sheet
Electrical Specifications
Parameter
ADC0 Always-on 4
Symbol
Test Condition
Min
Typ
Max
Unit
IADC
800 ksps, 10-bit conversions or
—
820
1200
μA
—
405
580
μA
200 ksps, VDD = 3.0 V
—
370
—
μA
100 ksps, VDD = 3.0 V
—
185
—
μA
10 ksps, VDD = 3.0 V
—
20
—
μA
200 ksps, VDD = 3.0 V
—
485
—
μA
100 ksps, VDD = 3.0 V
—
245
—
μA
10 ksps, VDD = 3.0 V
—
25
—
μA
100 ksps, VDD = 3.0 V
—
505
—
μA
50 ksps, VDD = 3.0 V
—
255
—
μA
10 ksps, VDD = 3.0 V
—
50
—
μA
100 ksps, VDD = 3.0 V,
—
950
—
μA
—
415
—
μA
—
80
—
μA
Normal Power Mode
—
680
790
μA
Low Power Mode
—
170
210
μA
—
70
120
μA
CPMD = 11
—
0.5
—
μA
CPMD = 10
—
3
—
μA
CPMD = 01
—
8.5
—
μA
CPMD = 00
—
22.5
—
μA
200 ksps, 12-bit conversions
Normal bias settings
VDD = 3.0 V
250 ksps, 10-bit conversions or
62.5 ksps 12-bit conversions
Low power bias settings
VDD = 3.0 V
ADC0 Burst Mode, 10-bit single
conversions, external reference
ADC0 Burst Mode, 10-bit single
conversions, internal reference,
Low power bias settings
ADC0 Burst Mode, 12-bit single
conversions, external reference
ADC0 Burst Mode, 12-bit single
conversions, internal reference
IADC
IADC
IADC
IADC
Normal bias
50 ksps, VDD = 3.0 V,
Low power bias
10 ksps, VDD = 3.0 V,
Low power bias
Internal ADC0 Reference, Alwayson 5
IVREFFS
Temperature Sensor
ITSENSE
Comparator 0 (CMP0, CMP1)
ICMP
Comparator Reference6
ICPREF
—
1.2
—
μA
Voltage Supply Monitor (VMON0)
IVMON
—
15
20
μA
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Rev. 1.3 | 18
EFM8UB1 Data Sheet
Electrical Specifications
Parameter
5V Regulator
Symbol
Test Condition
Min
Typ
Max
Unit
IVREG
Normal Mode
—
245
340
μA
—
60
100
μA
—
2.5
10
μA
—
2.5
—
nA
Low Energy Mode, 64 byte 1ms IN
Interrupt transfers
—
850
—
μA
Low Energy Mode, 64 byte 1ms
OUT Interrupt transfers
—
250
—
μA
Low Energy Mode, Idle (SOF only)
—
50
—
μA
(SUSEN = 0, BIASENB = 0)
Suspend Mode
(SUSEN = 1, BIASENB = 0)
Bias Disabled
(BIASENB = 1)
Disabled
(BIASENB = 1, REG1ENB = 1)
USB (USB0) Full-Speed
IUSB
Note:
1. Currents are additive. For example, where IDD is specified and the mode is not mutually exclusive, enabling the functions increases supply current by the specified amount.
2. Includes supply current from internal LDO regulator, supply monitor, and High Frequency Oscillator.
3. Includes supply current from internal LDO regulator, supply monitor, and Low Frequency Oscillator.
4. ADC0 always-on power excludes internal reference supply current.
5. The internal reference is enabled as-needed when operating the ADC in burst mode to save power.
6. This value is the current sourced from the pin or supply selected as the full-scale reference to the comparator DAC.
4.1.3 Reset and Supply Monitor
Table 4.3. Reset and Supply Monitor
Parameter
Symbol
VDD Supply Monitor Threshold
VVDDM
Power-On Reset (POR) Threshold
VPOR
Test Condition
Min
Typ
Max
Unit
1.95
2.05
2.15
V
Rising Voltage on VDD
—
1.2
—
V
Falling Voltage on VDD
0.75
—
1.36
V
VDD Ramp Time
tRMP
Time to VDD > 2.2 V
10
—
—
μs
Reset Delay from POR
tPOR
Relative to VDD > VPOR
3
10
31
ms
Time between release of reset
source and code execution
—
50
—
μs
15
—
—
μs
—
0.625
1.2
ms
Reset Delay from non-POR source tRST
RST Low Time to Generate Reset
tRSTL
Missing Clock Detector Response
Time (final rising edge to reset)
tMCD
Missing Clock Detector Trigger
Frequency
FMCD
—
7.5
13.5
kHz
VDD Supply Monitor Turn-On Time tMON
—
2
—
μs
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FSYSCLK >1 MHz
Rev. 1.3 | 19
EFM8UB1 Data Sheet
Electrical Specifications
4.1.4 Flash Memory
Table 4.4. Flash Memory
Parameter
Min
Typ
Max
Units
19
20
21
μs
5.2
5.35
5.5
ms
VDD Voltage During Programming 3 VPROG
2.2
—
3.6
V
Endurance (Write/Erase Cycles)
20k
100k
—
Cycles
—
5.5
—
µs
Write Time1 , 2
Symbol
Test Condition
tWRITE
One Byte,
FSYSCLK = 24.5 MHz
Erase Time1 , 2
tERASE
One Page,
FSYSCLK = 24.5 MHz
CRC Calculation Time
NWE
tCRC
One 256-Byte Block
SYSCLK = 48 MHz
Note:
1. Does not include sequencing time before and after the write/erase operation, which may be multiple SYSCLK cycles.
2. The internal High-Frequency Oscillator 0 has a programmable output frequency, which is factory programmed to 24.5 MHz. If
user firmware adjusts the oscillator speed, it must be between 22 and 25 MHz during any flash write or erase operation. It is
recommended to write the HFO0CAL register back to its reset value when writing or erasing flash.
3. Flash can be safely programmed at any voltage above the supply monitor threshold (VVDDM).
4. Data Retention Information is published in the Quarterly Quality and Reliability Report.
4.1.5 Power Management Timing
Table 4.5. Power Management Timing
Parameter
Symbol
Test Condition
Idle Mode Wake-up Time
tIDLEWK
Suspend Mode Wake-up Time
tSUS-
SYSCLK = HFOSC0
PENDWK
CLKDIV = 0x00
tSLEEPWK
SYSCLK = HFOSC0
Snooze Mode Wake-up Time
Min
Typ
Max
Units
2
—
3
SYSCLKs
—
170
—
ns
—
12
—
µs
CLKDIV = 0x00
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Rev. 1.3 | 20
EFM8UB1 Data Sheet
Electrical Specifications
4.1.6 Internal Oscillators
Table 4.6. Internal Oscillators
Parameter
Symbol
Test Condition
Min
Typ
Max
Unit
High Frequency Oscillator 0 (24.5 MHz)
Oscillator Frequency
fHFOSC0
Full Temperature and Supply
Range
24
24.5
25
MHz
Power Supply Sensitivity
PSSHFOS
TA = 25 °C
—
0.5
—
%/V
—
40
—
ppm/°C
47.3
48
48.7
MHz
—
0.02
—
%/V
TSHFOSC1 VDD = 3.0 V
—
45
—
ppm/°C
Oscillator Frequency
fLFOSC
75
80
85
kHz
Power Supply Sensitivity
PSSLFOSC TA = 25 °C
—
0.05
—
%/V
Temperature Sensitivity
TSLFOSC
—
65
—
ppm/°C
Min
Typ
Max
Unit
fCMOS
0
—
50
MHz
External Input CMOS Clock High
Time
tCMOSH
9
—
—
ns
External Input CMOS Clock Low
Time
tCMOSL
9
—
—
ns
C0
Temperature Sensitivity
TSHFOSC0 VDD = 3.0 V
High Frequency Oscillator 1 (48 MHz)
Oscillator Frequency
fHFOSC1
Full Temperature and Supply
Range
Power Supply Sensitivity
PSSHFOS
TA = 25 °C
C1
Temperature Sensitivity
Low Frequency Oscillator (80 kHz)
Full Temperature and Supply
Range
VDD = 3.0 V
4.1.7 External Clock Input
Table 4.7. External Clock Input
Parameter
External Input CMOS Clock
Symbol
Test Condition
Frequency (at EXTCLK pin)
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EFM8UB1 Data Sheet
Electrical Specifications
4.1.8 ADC
Table 4.8. ADC
Parameter
Resolution
Throughput Rate
Symbol
Test Condition
Nbits
12 Bit Mode
12
Bits
10 Bit Mode
10
Bits
fS
(High Speed Mode)
Throughput Rate
fS
(Low Power Mode)
Tracking Time
tTRK
Power-On Time
tPWR
SAR Clock Frequency
fSAR
Min
Typ
Max
Unit
12 Bit Mode
—
—
200
ksps
10 Bit Mode
—
—
800
ksps
12 Bit Mode
—
—
62.5
ksps
10 Bit Mode
—
—
250
ksps
High Speed Mode
230
—
—
ns
Low Power Mode
450
—
—
ns
1.2
—
—
μs
—
—
6.25
MHz
—
—
12.5
MHz
—
—
4
MHz
High Speed Mode,
Reference is 2.4 V internal
High Speed Mode,
Reference is not 2.4 V internal
Low Power Mode
Conversion Time
tCNV
10-Bit Conversion,
1.1
μs
SAR Clock = 12.25 MHz,
System Clock = 24.5 MHz.
Sample/Hold Capacitor
CSAR
Gain = 1
—
5
—
pF
Gain = 0.5
—
2.5
—
pF
Input Pin Capacitance
CIN
—
20
—
pF
Input Mux Impedance
RMUX
—
550
—
Ω
Voltage Reference Range
VREF
1
—
VDD
V
Input Voltage Range 1
VIN
Gain = 1
0
—
VREF
V
Gain = 0.5
0
—
2xVREF
V
—
70
—
dB
12 Bit Mode
—
±1
±2.3
LSB
10 Bit Mode
—
±0.2
±0.6
LSB
12 Bit Mode
-1
±0.7
1.9
LSB
10 Bit Mode
—
±0.2
±0.6
LSB
12 Bit Mode, VREF = 1.65 V
-3
0
3
LSB
10 Bit Mode, VREF = 1.65 V
-2
0
2
LSB
—
0.004
—
LSB/°C
Power Supply Rejection Ratio
PSRRADC
DC Performance
Integral Nonlinearity
INL
Differential Nonlinearity (Guaranteed Monotonic)
DNL
Offset Error
EOFF
Offset Temperature Coefficient
TCOFF
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EFM8UB1 Data Sheet
Electrical Specifications
Parameter
Slope Error
Symbol
Test Condition
Min
Typ
Max
Unit
EM
12 Bit Mode
—
±0.02
±0.1
%
10 Bit Mode
—
±0.06
±0.24
%
Dynamic Performance 10 kHz Sine Wave Input 1dB below full scale, Max throughput, using AGND pin
Signal-to-Noise
Signal-to-Noise Plus Distortion
SNR
SNDR
Total Harmonic Distortion (Up to
5th Harmonic)
THD
Spurious-Free Dynamic Range
SFDR
12 Bit Mode
61
66
—
dB
10 Bit Mode
53
60
—
dB
12 Bit Mode
61
66
—
dB
10 Bit Mode
53
60
—
dB
12 Bit Mode
—
71
—
dB
10 Bit Mode
—
70
—
dB
12 Bit Mode
—
-79
—
dB
10 Bit Mode
—
-70
—
dB
Note:
1. Absolute input pin voltage is limited by the VDD supply.
4.1.9 Voltage Reference
Table 4.9. Voltage Reference
Parameter
Symbol
Test Condition
Min
Typ
Max
Unit
VREFFS
1.65 V Setting
1.62
1.65
1.68
V
2.4 V Setting, VDD > 2.6 V
2.35
2.4
2.45
V
Internal Fast Settling Reference
Output Voltage
(Full Temperature and Supply
Range)
Temperature Coefficient
TCREFFS
—
50
—
ppm/°C
Turn-on Time
tREFFS
—
—
1.5
μs
Power Supply Rejection
PSRRREF
—
400
—
ppm/V
—
8
—
μA
FS
External Reference
Input Current
IEXTREF
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3.0 V
Rev. 1.3 | 23
EFM8UB1 Data Sheet
Electrical Specifications
4.1.10 Temperature Sensor
Table 4.10. Temperature Sensor
Parameter
Symbol
Test Condition
Min
Typ
Max
Unit
Offset
VOFF
TA = 0 °C
—
757
—
mV
Offset Error 1
EOFF
TA = 0 °C
—
17
—
mV
Slope
M
—
2.85
—
mV/°C
Slope Error 1
EM
—
70
—
μV/°
Linearity
—
0.5
—
°C
Turn-on Time
—
1.8
—
μs
Min
Typ
Max
Unit
1.78
1.85
1.92
V
Min
Typ
Max
Unit
3.0
—
5.25
V
3.1
3.3
3.6
V
—
VREGIN –
VDROPOUT
—
V
Note:
1. Represents one standard deviation from the mean.
4.1.11 1.8 V Internal LDO Voltage Regulator
Table 4.11. 1.8V Internal LDO Voltage Regulator
Parameter
Output Voltage
Symbol
Test Condition
VOUT_1.8V
4.1.12 5 V Voltage Regulator
Table 4.12. 5V Voltage Regulator
Parameter
Symbol
Input Voltage Range 1
VREGIN
Output Voltage on VDD 2
VREGOUT
Test Condition
Output Current = 1 to 100 mA
Regulation range (VREGIN ≥ 4.1V)
Output Current = 1 to 100 mA
Dropout range (VREGIN < 4.1V)
Output Current 2
IREGOUT
—
—
100
mA
Dropout Voltage
VDROPOUT Output Current = 100 mA
—
—
0.8
V
Note:
1. Input range to meet the Output Voltage on VDD specification. If the 5 V voltage regulator is not used, VREGIN should be tied to
VDD.
2. Output current is total regulator output, including any current required by the device.
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EFM8UB1 Data Sheet
Electrical Specifications
4.1.13 Comparators
Table 4.13. Comparators
Parameter
Min
Typ
Max
Unit
+100 mV Differential, VCM = 1.65 V
—
110
—
ns
-100 mV Differential, VCM = 1.65 V
—
160
—
ns
Response Time, CPMD = 11 (Low- tRESP3
est Power)
+100 mV Differential, VCM = 1.65 V
—
1.2
—
μs
-100 mV Differential, VCM = 1.65 V
—
4.5
—
μs
Positive Hysteresis
CPHYP = 00
—
0.4
—
mV
CPHYP = 01
—
8
—
mV
CPHYP = 10
—
16
—
mV
CPHYP = 11
—
32
—
mV
CPHYN = 00
—
-0.4
—
mV
CPHYN = 01
—
-8
—
mV
CPHYN = 10
—
-16
—
mV
CPHYN = 11
—
-32
—
mV
CPHYP = 00
—
1.5
—
mV
CPHYP = 01
—
4
—
mV
CPHYP = 10
—
8
—
mV
CPHYP = 11
—
16
—
mV
CPHYN = 00
—
-1.5
—
mV
CPHYN = 01
—
-4
—
mV
CPHYN = 10
—
-8
—
mV
CPHYN = 11
—
-16
—
mV
-0.25
—
VDD+0.25
V
VDD
V
Response Time, CPMD = 00
(Highest Speed)
Symbol
Test Condition
tRESP0
HYSCP+
Mode 0 (CPMD = 00)
Negative Hysteresis
HYSCP-
Mode 0 (CPMD = 00)
Positive Hysteresis
HYSCP+
Mode 3 (CPMD = 11)
Negative Hysteresis
HYSCP-
Mode 3 (CPMD = 11)
Input Range (CP+ or CP-)
VIN
Direct comparator input
Reference DAC input
1.2
Reference DAC Resolution
Nbits
Reference DAC Input Impedance
RCPREF
—
2.75
—
MΩ
Input Pin Capacitance
CCP
—
7.5
—
pF
Common-Mode Rejection Ratio
CMRRCP
—
70
—
dB
Power Supply Rejection Ratio
PSRRCP
—
72
—
dB
Input Offset Voltage
VOFF
-10
0
10
mV
Input Offset Tempco
TCOFF
—
3.5
—
μV/°
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6
TA = 25 °C
bits
Rev. 1.3 | 25
EFM8UB1 Data Sheet
Electrical Specifications
4.1.14 Port I/O
Table 4.14. Port I/O
Parameter
Min
Typ
Max
Unit
IOH = -7 mA, VIO ≥ 3.0 V
VIO - 0.7
—
—
V
IOH = -3.3 mA, 2.2 V ≤ VIO < 3.0 V
VIO x 0.8
—
—
V
IOL = 13.5 mA, VIO ≥ 3.0 V
—
—
0.6
V
IOL = 7 mA, 2.2 V ≤ VIO < 3.0 V
—
—
VIO x 0.2
V
IOH = -4.75 mA, VIO ≥ 3.0 V
VIO - 0.7
—
—
V
IOH = -2.25 mA, 2.2 V ≤ VIO < 3.0 V
VIO x 0.8
—
—
V
IOL = 6.5 mA, VIO ≥ 3.0 V
—
—
0.6
V
IOL = 3.5 mA, 2.2 V ≤ VIO < 3.0 V
—
—
VIO x 0.2
V
VIH
VIO - 0.6
—
—
V
VIL
—
—
0.6
V
Pin Capacitance
CIO
—
7
—
pF
Weak Pull-Up Current
IPU
VIO = 3.6
-30
-20
-10
μA
Input Leakage (Pullups off or Analog)
ILK
GND < VIN < VIO
-1.1
—
1.1
μA
Input Leakage Current with VIN
above VIO
ILK
VIO < VIN < VIO+2.0 V
0
5
150
μA
Output High Voltage (High Drive)1
Symbol
Test Condition
VOH
IOH = -1.8 mA, 1.71 V ≤ VIO < 2.2 V
Output Low Voltage (High Drive)1
VOL
IOL = 3.6 mA, 1.71 V ≤ VIO < 2.2 V
Output High Voltage (Low Drive)1
VOH
IOH = -1.2 mA, 1.71 V ≤ VIO < 2.2 V
Output Low Voltage (Low Drive)1
VOL
IOL = 1.8 mA, 1.71 V ≤ VIO < 2.2 V
Input High Voltage
(all port pins including VBUS)
Input Low Voltage
(all port pins including VBUS)
(VIN = 0 V)
Note:
1. See Figure 4.7 Typical VOH Curves on page 34 and Figure 4.8 Typical VOL Curves on page 34 for more information.
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Rev. 1.3 | 26
EFM8UB1 Data Sheet
Electrical Specifications
4.1.15 USB Transceiver
Table 4.15. USB Transceiver
Parameter
Symbol
Test Condition
Min
Typ
Max
Unit
Output High Voltage
VOH
VDD ≥3.0V
2.8
—
—
V
Output Low Voltage
VOL
VDD ≥3.0V
—
—
0.8
V
Output Crossover Point
VCRS
1.3
—
2.0
V
Output Impedance
ZDRV
Driving High
28
36
44
Ω
Driving Low
28
36
44
1.425
1.5
1.575
kΩ
Low Speed
75
—
300
ns
Full Speed
4
—
20
ns
Low Speed
75
—
300
ns
Full Speed
4
—
20
ns
0.2
—
—
V
0.8
—
2.5
V
—
3.3 V
GND-0.3
5.8
V
VIO < 3.3 V
GND-0.3
VIO+2.5
V
Total Current Sunk into Supply Pin
IVDD
─
400
mA
Total Current Sourced out of Ground
Pin
IGND
400
─
mA
Current Sourced or Sunk by any I/O
Pin or RSTb
IIO
-100
100
mA
Operating Junction Temperature
TJ
-40
105
°C
Note:
1. Exposure to maximum rating conditions for extended periods may affect device reliability.
2. On devices without a VIO pin, VIO = VDD
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Rev. 1.3 | 30
EFM8UB1 Data Sheet
Electrical Specifications
4.4 Typical Performance Curves
Figure 4.2. Typical Operating Supply Current using HFOSC0
Figure 4.3. Typical Operating Supply Current using HFOSC1
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Rev. 1.3 | 31
EFM8UB1 Data Sheet
Electrical Specifications
Figure 4.4. Typical Operating Supply Current using LFOSC
Figure 4.5. Typical ADC0 and Internal Reference Supply Current in Burst Mode
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Rev. 1.3 | 32
EFM8UB1 Data Sheet
Electrical Specifications
Figure 4.6. Typical ADC0 Supply Current in Normal (always-on) Mode
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Rev. 1.3 | 33
EFM8UB1 Data Sheet
Electrical Specifications
Figure 4.7. Typical VOH Curves
Figure 4.8. Typical VOL Curves
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Rev. 1.3 | 34
EFM8UB1 Data Sheet
Typical Connection Diagrams
5. Typical Connection Diagrams
5.1 Power
The figure below shows a typical connection diagram for the power pins of the EFM8UB1 devices when the internal regulator used and
USB is connected (bus-powered).
EFM8UB1 Device
USB 5 V (in)
4.7 µF and 0.1 µF bypass
capacitors required for
each power pin placed as
close to the pins as
possible.
3.3 V (out)
VREGIN
Voltage
Regulator
VDD
GND
Figure 5.1. Connection Diagram with Voltage Regulator Used and USB Connected (Bus-Powered)
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Rev. 1.3 | 35
EFM8UB1 Data Sheet
Typical Connection Diagrams
The figure below shows a typical connection diagram for the power pins of the EFM8UB1 devices when the internal regulator used and
USB is connected (self-powered).
EFM8UB1 Device
3.6-5.25 V (in)
4.7 µF and 0.1 µF bypass
capacitors required for
each power pin placed as
close to the pins as
possible.
3.3 V (out)
VREGIN
Voltage
Regulator
VDD
GND
Figure 5.2. Connection Diagram with Voltage Regulator Used and USB Connected (Self-Powered)
The figure below shows a typical connection diagram for the power pins of the EFM8UB1 devices when the internal 5 V-to-3.3 V regulator is not used.
EFM8UB1 Device
2.2-3.6 V (in)
VREGIN
4.7 µF and 0.1 µF bypass
capacitors required for
each power pin placed as
close to the pins as
possible.
Voltage
Regulator
VDD
GND
Figure 5.3. Connection Diagram with Voltage Regulator Not Used (Self-Powered)
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Rev. 1.3 | 36
EFM8UB1 Data Sheet
Typical Connection Diagrams
5.2 USB
Figure 5.4 Bus-Powered Connection Diagram for USB Pins on page 37 shows a typical connection bus-powered diagram for the USB
pins of the EFM8UB1 devices including ESD protection diodes on the USB pins. Bypass capacitors on VREGIN and VDD are required
as discussed in 5.1 Power, but are not shown in the figure.
Note: The VBUS pin is not required as a sensing pin for proper operation in bus-powered configurations. Rather than using VBUS as a
sensing pin, it is recommended to use the VBUS pin only as a GPIO by clearing VBUSEN and VBUSIE to 0 in the USB0CF register. To
do this using the USB stack, set the device to use bus-powered mode.
EFM8UB1 Device
VBUS
USB
Connector
VREGIN
D+
D+
D-
USB
D-
Signal GND
SP0503BAHT or
equivalent USB ESD
protection diodes
(Recommended)
GND
Figure 5.4. Bus-Powered Connection Diagram for USB Pins
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Rev. 1.3 | 37
EFM8UB1 Data Sheet
Typical Connection Diagrams
Figure 5.5 Self-Powered Connection Diagram for USB Pins on page 38 shows a typical connection self-powered diagram for the USB
pins of the EFM8UB1 devices including ESD protection diodes on the USB pins.
Note: There are two relevant restrictions on the VBUS pin voltage in this self-powered configuration. The first is the absolute maximum
voltage on the VBUS pin, which is defined as VIO + 2.5 V in Table 4.19 Absolute Maximum Ratings on page 30. The second is the
Input High Voltage (VIH) for VBUS to detect when the device is connected to a bus, which is defined as VIO – 0.6 V in 4.1.14 Port I/O.
For self-powered systems where VDD and VIO may be unpowered when VBUS is connected to 4.4 V to 5.5 V, a resistor divider (or
functionally-equivalent circuit) on VBUS is required to meet these specifications and ensure reliable device operation. In this case, the
current limitation of the resistor divider prevents overstress on the pin, even though the VIO + 2.5 V specification is not strictly met.
22.1 kΩ
EFM8UB1 Device
47.5 kΩ
VBUS
USB
Connector
P3.1 / VBUS
D+
D+
D-
USB
D-
Signal GND
SP0503BAHT or
equivalent USB ESD
protection diodes
(Recommended)
GND
Figure 5.5. Self-Powered Connection Diagram for USB Pins
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Rev. 1.3 | 38
EFM8UB1 Data Sheet
Typical Connection Diagrams
5.3 Debug
The diagram below shows a typical connection diagram for the debug connections pins. The pin sharing resistors are only required if
the functionality on the C2D (a GPIO pin) and the C2CK (RSTb) is routed to external circuitry. For example, if the RSTb pin is connected to an external switch with debouncing filter or if the GPIO sharing with the C2D pin is connected to an external circuit, the pin sharing resistors and connections to the debug adapter must be placed on the hardware. Otherwise, these components and connections
can be omitted.
For more information on debug connections, see the example schematics and information available in AN124: Pin Sharing Techniques
for the C2 Interface. Application notes can be found on the Silicon Labs website (http://www.silabs.com/8bit-appnotes) or in Simplicity
Studio.
VDD
EFM8UB1 Device
C2CK
1k
1k
External
System
1k
(if pin sharing)
C2D
(if pin sharing)
1k
1k
GND
Debug Adapter
Figure 5.6. Debug Connection Diagram
5.4 Other Connections
Other components or connections may be required to meet the system-level requirements. Application Note AN203: 8-bit MCU Printed
Circuit Board Design Notes contains detailed information on these connections. Application Notes can be accessed on the Silicon Labs
website (www.silabs.com/8bit-appnotes).
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Rev. 1.3 | 39
EFM8UB1 Data Sheet
Pin Definitions
6. Pin Definitions
P0.2
P0.3
P0.4
P0.5
P0.6
P0.7
P1.0
28
27
26
25
24
23
22
6.1 EFM8UB1x-QFN28 Pin Definitions
P0.1
1
21
P1.1
P0.0
2
20
P1.2
GND
3
19
P1.3
D+
4
18
P1.4
D-
5
17
P1.5
VDD
6
16
P1.6
VREGIN
7
15
P1.7
28 pin QFN
(Top View)
9
10
11
12
13
14
RSTb / C2CK
P3.0 / C2D
P2.3
P2.2
P2.1
P2.0
P3.1 / VBUS
8
GND
Figure 6.1. EFM8UB1x-QFN28 Pinout
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Rev. 1.3 | 40
EFM8UB1 Data Sheet
Pin Definitions
Table 6.1. Pin Definitions for EFM8UB1x-QFN28
Pin
Pin Name
Description
Crossbar Capability
Additional Digital
Functions
Analog Functions
P0.1
Multifunction I/O
Yes
P0MAT.1
ADC0.1
INT0.1
CMP0P.1
INT1.1
CMP0N.1
Number
1
AGND
2
P0.0
Multifunction I/O
Yes
P0MAT.0
ADC0.0
INT0.0
CMP0P.0
INT1.0
CMP0N.0
VREF
3
GND
Ground
4
D+
USB Data Positive
ADC0.28
5
D-
USB Data Negative
ADC0.29
6
VDD
Supply Power Input /
5V Regulator Output
7
VREGIN
5V Regulator Input
8
P3.1
Multifunction I/O
9
RST /
Active-low Reset /
C2CK
C2 Debug Clock
P3.0 /
Multifunction I/O /
C2D
C2 Debug Data
P2.3
Multifunction I/O
10
11
VBUS
Yes
P2MAT.3
ADC0.23
CMP1P.12
CMP1N.12
12
P2.2
Multifunction I/O
Yes
P2MAT.2
ADC0.22
CMP1P.11
CMP1N.11
13
P2.1
Multifunction I/O
Yes
P2MAT.1
ADC0.21
CMP1P.10
CMP1N.10
14
P2.0
Multifunction I/O
Yes
P2MAT.0
ADC0.20
CMP1P.9
CMP1N.9
15
P1.7
Multifunction I/O
Yes
P1MAT.7
ADC0.15
CMP1P.7
CMP1N.7
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Rev. 1.3 | 41
EFM8UB1 Data Sheet
Pin Definitions
Pin
Pin Name
Description
Crossbar Capability
Additional Digital
Functions
Analog Functions
P1.6
Multifunction I/O
Yes
P1MAT.6
ADC0.14
I2C0_SCL
CMP1P.6
Number
16
CMP1N.6
17
P1.5
Multifunction I/O
Yes
P1MAT.5
ADC0.13
I2C0_SDA
CMP1P.5
CMP1N.5
18
P1.4
Multifunction I/O
Yes
P1MAT.4
ADC0.12
CMP1P.4
CMP1N.4
19
P1.3
Multifunction I/O
Yes
P1MAT.3
ADC0.11
CMP1P.3
CMP1N.3
20
P1.2
Multifunction I/O
Yes
P1MAT.2
ADC0.10
CMP1P.2
CMP1N.2
21
P1.1
Multifunction I/O
Yes
P1MAT.1
ADC0.9
CMP1P.1
CMP1N.1
CMP0P.10
CMP0N.10
22
P1.0
Multifunction I/O
Yes
P1MAT.0
ADC0.8
CMP1P.0
CMP1N.0
CMP0P.9
CMP0N.9
23
24
P0.7
P0.6
Multifunction I/O
Multifunction I/O
Yes
Yes
P0MAT.7
ADC0.7
INT0.7
CMP0P.7
INT1.7
CMP0N.7
P0MAT.6
ADC0.6
CNVSTR
CMP0P.6
INT0.6
CMP0N.6
INT1.6
25
P0.5
Multifunction I/O
Yes
P0MAT.5
ADC0.5
INT0.5
CMP0P.5
INT1.5
CMP0N.5
UART0_RX
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Rev. 1.3 | 42
EFM8UB1 Data Sheet
Pin Definitions
Pin
Pin Name
Description
Crossbar Capability
Additional Digital
Functions
Analog Functions
P0.4
Multifunction I/O
Yes
P0MAT.4
ADC0.4
INT0.4
CMP0P.4
INT1.4
CMP0N.4
Number
26
UART0_TX
27
P0.3
Multifunction I/O
Yes
P0MAT.3
ADC0.3
EXTCLK
CMP0P.3
INT0.3
CMP0N.3
INT1.3
28
Center
P0.2
GND
Multifunction I/O
Yes
P0MAT.2
ADC0.2
INT0.2
CMP0P.2
INT1.2
CMP0N.2
Ground
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Rev. 1.3 | 43
EFM8UB1 Data Sheet
Pin Definitions
6.2 EFM8UB1x-QSOP24 Pin Definitions
P0.2
1
24
P0.3
P0.1
2
23
P0.4
P0.0
3
22
P0.5
GND
4
21
P0.6
D+
5
20
P0.7
D-
6
19
P1.0
VIO
7
18
P1.1
VDD
8
17
P1.2
VREGIN
9
16
P1.3
P3.1 / VBUS
10
15
P1.4
RSTb / C2CK
11
14
P1.5
P2.0 / C2D
12
13
P1.6
24 pin QSOP
(Top View)
Figure 6.2. EFM8UB1x-QSOP24 Pinout
Table 6.2. Pin Definitions for EFM8UB1x-QSOP24
Pin
Pin Name
Description
Crossbar Capability
Additional Digital
Functions
Analog Functions
P0.2
Multifunction I/O
Yes
P0MAT.2
ADC0.2
INT0.2
CMP0P.2
INT1.2
CMP0N.2
P0MAT.1
ADC0.1
INT0.1
CMP0P.1
INT1.1
CMP0N.1
Number
1
2
P0.1
Multifunction I/O
Yes
AGND
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Rev. 1.3 | 44
EFM8UB1 Data Sheet
Pin Definitions
Pin
Pin Name
Description
Crossbar Capability
Additional Digital
Functions
Analog Functions
P0.0
Multifunction I/O
Yes
P0MAT.0
ADC0.0
INT0.0
CMP0P.0
INT1.0
CMP0N.0
Number
3
VREF
4
GND
Ground
5
D+
USB Data Positive
ADC0.28
6
D-
USB Data Negative
ADC0.29
7
VIO
I/O Power Input
8
VDD
Supply Power Input /
5V Regulator Output
9
VREGIN
5V Regulator Input
10
P3.1
Multifunction I/O
11
RSTb /
Active-low Reset /
C2CK
C2 Debug Clock
P2.0 /
Multifunction I/O /
C2D
C2 Debug Data
P1.6
Multifunction I/O
12
13
VBUS
Yes
P1MAT.6
ADC0.14
CMP1P.9
CMP1N.9
14
P1.5
Multifunction I/O
Yes
P1MAT.5
ADC0.13
CMP1P.7
CMP1N.7
15
P1.4
Multifunction I/O
Yes
P1MAT.4
ADC0.12
CMP1P.6
CMP1N.6
16
P1.3
Multifunction I/O
Yes
P1MAT.3
ADC0.11
CMP1P.5
CMP1N.5
17
P1.2
Multifunction I/O
Yes
P1MAT.2
ADC0.10
I2C0_SCL
CMP1P.4
CMP1N.4
18
P1.1
Multifunction I/O
Yes
P1MAT.1
ADC0.9
I2C0_SDA
CMP1P.3
CMP1N.3
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Rev. 1.3 | 45
EFM8UB1 Data Sheet
Pin Definitions
Pin
Pin Name
Description
Crossbar Capability
Additional Digital
Functions
Analog Functions
P1.0
Multifunction I/O
Yes
P1MAT.0
ADC0.8
Number
19
CMP1P.2
CMP1N.2
20
P0.7
Multifunction I/O
Yes
P0MAT.7
ADC0.7
INT0.7
CMP1P.1
INT1.7
CMP1N.1
CMP0P.7
CMP0N.7
21
P0.6
Multifunction I/O
Yes
P0MAT.6
ADC0.6
CNVSTR
CMP1P.0
INT0.6
CMP1N.0
INT1.6
CMP0P.6
CMP0N.6
22
P0.5
Multifunction I/O
Yes
P0MAT.5
ADC0.5
INT0.5
CMP0P.5
INT1.5
CMP0N.5
UART0_RX
23
P0.4
Multifunction I/O
Yes
P0MAT.4
ADC0.4
INT0.4
CMP0P.4
INT1.4
CMP0N.4
UART0_TX
24
P0.3
Multifunction I/O
Yes
P0MAT.3
ADC0.3
EXTCLK
CMP0P.3
INT0.3
CMP0N.3
INT1.3
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Rev. 1.3 | 46
EFM8UB1 Data Sheet
Pin Definitions
D-
5
P0.3
P0.4
P0.5
19
18
17
GND
6
VREGIN
VDD
(Top View)
10
4
P2.0 / C2D
D+
16
20 pin QFN
9
3
RSTb / C2CK
GND
8
2
P3.1 / VBUS
P0.0
P0.2
1
7
P0.1
20
6.3 EFM8UB1x-QFN20 Pin Definitions
P0.6
15
P0.7
14
P1.0
13
P1.1
12
GND
11
P1.2
Figure 6.3. EFM8UB1x-QFN20 Pinout
Table 6.3. Pin Definitions for EFM8UB1x-QFN20
Pin
Pin Name
Description
Crossbar Capability
Additional Digital
Functions
Analog Functions
P0.1
Multifunction I/O
Yes
P0MAT.1
ADC0.1
INT0.1
CMP0P.1
INT1.1
CMP0N.1
Number
1
AGND
2
P0.0
Multifunction I/O
Yes
P0MAT.0
ADC0.0
INT0.0
CMP0P.0
INT1.0
CMP0N.0
VREF
3
GND
Ground
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Rev. 1.3 | 47
EFM8UB1 Data Sheet
Pin Definitions
Pin
Pin Name
Description
Crossbar Capability
4
D+
USB Data Positive
ADC0.28
5
D-
USB Data Negative
ADC0.29
6
VDD
Supply Power Input /
Number
Additional Digital
Functions
Analog Functions
5V Regulator Output
7
VREGIN
5V Regulator Input
8
P3.1
Multifunction I/O
9
RST /
Active-low Reset /
C2CK
C2 Debug Clock
P2.0 /
Multifunction I/O /
C2D
C2 Debug Data
P1.2
Multifunction I/O
10
11
VBUS
Yes
P1MAT.2
ADC0.10
I2C0_SCL
CMP1P.4
CMP1N.4
12
GND
Ground
13
P1.1
Multifunction I/O
Yes
P1MAT.1
ADC0.9
I2C0_SDA
CMP1P.3
CMP1N.3
14
P1.0
Multifunction I/O
Yes
P1MAT.0
ADC0.8
CMP1P.2
CMP1N.2
15
P0.7
Multifunction I/O
Yes
P0MAT.7
ADC0.7
INT0.7
CMP1P.1
INT1.7
CMP1N.1
CMP0P.7
CMP0N.7
16
P0.6
Multifunction I/O
Yes
P0MAT.6
ADC0.6
CNVSTR
CMP1P.0
INT0.6
CMP1N.0
INT1.6
CMP0P.6
CMP0N.6
17
P0.5
Multifunction I/O
Yes
P0MAT.5
ADC0.5
INT0.5
CMP0P.5
INT1.5
CMP0N.5
UART0_RX
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Rev. 1.3 | 48
EFM8UB1 Data Sheet
Pin Definitions
Pin
Pin Name
Description
Crossbar Capability
Additional Digital
Functions
Analog Functions
P0.4
Multifunction I/O
Yes
P0MAT.4
ADC0.4
INT0.4
CMP0P.4
INT1.4
CMP0N.4
Number
18
UART0_TX
19
P0.3
Multifunction I/O
Yes
P0MAT.3
ADC0.3
EXTCLK
CMP0P.3
INT0.3
CMP0N.3
INT1.3
20
Center
P0.2
GND
Multifunction I/O
Yes
P0MAT.2
ADC0.2
INT0.2
CMP0P.2
INT1.2
CMP0N.2
Ground
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Rev. 1.3 | 49
EFM8UB1 Data Sheet
QFN28 Package Specifications
7. QFN28 Package Specifications
7.1 QFN28 Package Dimensions
Figure 7.1. QFN28 Package Drawing
Table 7.1. QFN28 Package Dimensions
Dimension
Min
Typ
Max
A
0.70
0.75
0.80
A1
0.00
—
0.05
A3
b
0.20 REF
0.20
D
D2
0.25
0.30
5.00 BSC
3.15
3.25
e
0.50 BSC
E
5.00 BSC
3.35
E2
3.15
3.25
3.35
L
0.45
0.55
0.65
aaa
0.10
bbb
0.10
ddd
0.05
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Rev. 1.3 | 50
EFM8UB1 Data Sheet
QFN28 Package Specifications
Dimension
Min
Typ
eee
0.08
Z
0.44
Y
0.18
Max
Note:
1. All dimensions shown are in millimeters (mm) unless otherwise noted.
2. Dimensioning and Tolerancing per ANSI Y14.5M-1994.
3. This drawing conforms to JEDEC outline MO-220 except for custom features D2, E2, L, Z, and Y which are toleranced per supplier designation.
4. Recommended card reflow profile is per the JEDEC/IPC J-STD-020 specification for Small Body Components.
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Rev. 1.3 | 51
EFM8UB1 Data Sheet
QFN28 Package Specifications
7.2 QFN28 PCB Land Pattern
X1
C2
Y2
Y1
C0.35
E
X2
C1
Figure 7.2. QFN28 PCB Land Pattern Drawing
Table 7.2. QFN28 PCB Land Pattern Dimensions
Dimension
Min
Max
C1
4.80
C2
4.80
E
0.50
X1
0.30
X2
3.35
Y1
0.95
Y2
3.35
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Rev. 1.3 | 52
EFM8UB1 Data Sheet
QFN28 Package Specifications
Dimension
Min
Max
Note:
1. All dimensions shown are in millimeters (mm) unless otherwise noted.
2. This Land Pattern Design is based on the IPC-7351 guidelines.
3. All metal pads are to be non-solder mask defined (NSMD). Clearance between the solder mask and the metal pad is to be 60 µm
minimum, all the way around the pad.
4. A stainless steel, laser-cut and electro-polished stencil with trapezoidal walls should be used to assure good solder paste release.
5. The stencil thickness should be 0.125 mm (5 mils).
6. The ratio of stencil aperture to land pad size should be 1:1 for all perimeter pads.
7. A 2 x 2 array of 1.2 mm square openings on a 1.5 mm pitch should be used for the center pad.
8. A No-Clean, Type-3 solder paste is recommended.
9. The recommended card reflow profile is per the JEDEC/IPC J-STD-020 specification for Small Body Components.
7.3 QFN28 Package Marking
EFM8
PPPPPPPP
TTTTTT
YYWW #
Figure 7.3. QFN28 Package Marking
The package marking consists of:
• PPPPPPPP – The part number designation.
• TTTTTT – A trace or manufacturing code.
• YY – The last 2 digits of the assembly year.
• WW – The 2-digit workweek when the device was assembled.
• # – The device revision (A, B, etc.).
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Rev. 1.3 | 53
EFM8UB1 Data Sheet
QSOP24 Package Specifications
8. QSOP24 Package Specifications
8.1 Package Dimensions
Figure 8.1. Package Drawing
Table 8.1. Package Dimensions
Dimension
Min
Typ
Max
A
—
—
1.75
A1
0.10
—
0.25
b
0.20
—
0.30
c
0.10
—
0.25
D
8.65 BSC
E
6.00 BSC
E1
3.90 BSC
e
0.635 BSC
L
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0.40
—
1.27
Rev. 1.3 | 54
EFM8UB1 Data Sheet
QSOP24 Package Specifications
Dimension
theta
Min
Typ
Max
0º
—
8º
aaa
0.20
bbb
0.18
ccc
0.10
ddd
0.10
Note:
1. All dimensions shown are in millimeters (mm) unless otherwise noted.
2. Dimensioning and Tolerancing per ANSI Y14.5M-1994.
3. This drawing conforms to JEDEC outline MO-137, variation AE.
4. Recommended card reflow profile is per the JEDEC/IPC J-STD-020 specification for Small Body Components.
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Rev. 1.3 | 55
EFM8UB1 Data Sheet
QSOP24 Package Specifications
8.2 PCB Land Pattern
Figure 8.2. PCB Land Pattern Drawing
Table 8.2. PCB Land Pattern Dimensions
Dimension
Min
Max
C
5.20
5.30
E
0.635 BSC
X
0.30
0.40
Y
1.50
1.60
Note:
1. All dimensions shown are in millimeters (mm) unless otherwise noted.
2. This land pattern design is based on the IPC-7351 guidelines.
3. All metal pads are to be non-solder mask defined (NSMD). Clearance between the solder mask and the metal pad is to be 60 µm
minimum, all the way around the pad.
4. A stainless steel, laser-cut and electro-polished stencil with trapezoidal walls should be used to assure good solder paste release.
5. The stencil thickness should be 0.125 mm (5 mils).
6. The ratio of stencil aperture to land pad size should be 1:1 for all perimeter pads.
7. A No-Clean, Type-3 solder paste is recommended.
8. The recommended card reflow profile is per the JEDEC/IPC J-STD-020 specification for Small Body Components.
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Rev. 1.3 | 56
EFM8UB1 Data Sheet
QSOP24 Package Specifications
8.3 Package Marking
EFM8
PPPPPPPP #
TTTTTTYYWW
Figure 8.3. Package Marking
The package marking consists of:
• PPPPPPPP – The part number designation.
• TTTTTT – A trace or manufacturing code.
• YY – The last 2 digits of the assembly year.
• WW – The 2-digit workweek when the device was assembled.
• # – The device revision (A, B, etc.).
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Rev. 1.3 | 57
EFM8UB1 Data Sheet
QFN20 Package Specifications
9. QFN20 Package Specifications
9.1 QFN20 Package Dimensions
Figure 9.1. QFN20 Package Drawing
Table 9.1. QFN20 Package Dimensions
Dimension
Min
Typ
Max
A
0.70
0.75
0.80
A1
0.00
0.02
0.05
A3
0.20 REF
b
0.18
0.25
0.30
c
0.25
0.30
0.35
D
D2
3.00 BSC
1.6
1.70
e
0.50 BSC
E
3.00 BSC
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1.80
Rev. 1.3 | 58
EFM8UB1 Data Sheet
QFN20 Package Specifications
Dimension
Min
Typ
Max
E2
1.60
1.70
1.80
f
L
2.50 BSC
0.30
K
R
0.40
0.50
0.25 REF
0.09
0.125
aaa
0.15
bbb
0.10
ccc
0.10
ddd
0.05
eee
0.08
fff
0.10
0.15
Note:
1. All dimensions shown are in millimeters (mm) unless otherwise noted.
2. Dimensioning and Tolerancing per ANSI Y14.5M-1994.
3. The drawing complies with JEDEC MO-220.
4. Recommended card reflow profile is per the JEDEC/IPC J-STD-020 specification for Small Body Components.
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Rev. 1.3 | 59
EFM8UB1 Data Sheet
QFN20 Package Specifications
9.2 QFN20 PCB Land Pattern
Figure 9.2. QFN20 PCB Land Pattern Drawing
Table 9.2. QFN20 PCB Land Pattern Dimensions
Dimension
Min
Max
C1
3.10
C2
3.10
C3
2.50
C4
2.50
E
0.50
X1
0.30
X2
0.25
0.35
X3
1.80
Y1
0.90
Y2
Y3
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0.25
0.35
1.80
Rev. 1.3 | 60
EFM8UB1 Data Sheet
QFN20 Package Specifications
Dimension
Min
Max
Note:
1. All dimensions shown are in millimeters (mm) unless otherwise noted.
2. Dimensioning and Tolerancing is per the ANSI Y14.5M-1994 specification.
3. This Land Pattern Design is based on the IPC-7351 guidelines.
4. All metal pads are to be non-solder mask defined (NSMD). Clearance between the solder mask and the metal pad is to be 60 µm
minimum, all the way around the pad.
5. A stainless steel, laser-cut and electro-polished stencil with trapezoidal walls should be used to assure good solder paste release.
6. The stencil thickness should be 0.125 mm (5 mils).
7. The ratio of stencil aperture to land pad size should be 1:1 for the perimeter pads.
8. A 2 x 2 array of 0.75 mm openings on a 0.95 mm pitch should be used for the center pad to assure proper paste volume.
9. A No-Clean, Type-3 solder paste is recommended.
10. The recommended card reflow profile is per the JEDEC/IPC J-STD-020 specification for Small Body Components.
9.3 QFN20 Package Marking
PPPP
PPPP
TTTTTT
YYWW #
Figure 9.3. QFN20 Package Marking
The package marking consists of:
• PPPPPPPP – The part number designation.
• TTTTTT – A trace or manufacturing code.
• YY – The last 2 digits of the assembly year.
• WW – The 2-digit workweek when the device was assembled.
• # – The device revision (A, B, etc.).
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Rev. 1.3 | 61
EFM8UB1 Data Sheet
Revision History
10. Revision History
Revision 1.3
October 20th, 2017
• Updated Figure 3.1 Detailed EFM8UB1 Block Diagram on page 6 to show 1024 bytes of XRAM in the core, since the 1024 bytes of
USB FIFO RAM are documented in the USB block.
• Updated 3.1 Introduction to mention all device documentation.
• Updated text and figures in 5.1 Power to remove mention of the VBUS pin.
• Updated Figure 5.2 Connection Diagram with Voltage Regulator Used and USB Connected (Self-Powered) on page 36 to remove
VBUS pin.
• Updated the title of Figure 5.3 Connection Diagram with Voltage Regulator Not Used (Self-Powered) on page 36 to include "SelfPowered".
• Updated 5.2 USB to add a note regarding VBUS.
• Updated the maximum Voltage Reference Range specification to reference VDD instead of VIO in 4.1.8 ADC.
• Updated the maximum Input Range (CP+ or CP-) specification to reference VDD instead of VIO in 4.1.13 Comparators.
• Updated Weak Pull-Up Current specification condition to refer to VIO instead of VDD in 4.1.14 Port I/O.
• Added Z and Y dimensions and updated Note 3 in Table 7.1 QFN28 Package Dimensions on page 50.
• Updated the QFN20 and QSOP24 C2D pins to not available on the crossbar in 6.3 EFM8UB1x-QFN20 Pin Definitions and
6.2 EFM8UB1x-QSOP24 Pin Definitions.
Revision 1.2
March 15th, 2017
• Updated Figure 5.6 Debug Connection Diagram on page 39 to move the pull-up resistor on C2D / RSTb to after the series resistor
instead of before.
• Added a reference to AN945: EFM8 Factory Bootloader User Guide in 3.10 Bootloader.
•
•
•
•
Added bootloader pinout information to 3.10 Bootloader.
Added a note to 3.1 Introduction referencing the Reference Manual.
Specified the sizes of the SMBus and I2CSLAVE transmit and receive FIFOs.
Added a note to Table 4.2 Power Consumption on page 17 providing more information about the Comparator Reference specification.
Adjusted the Normal Mode and Idle Mode typical and maximum numbers in Table 4.2 Power Consumption on page 17 for FSYSCLK
= 48 MHz and FSYSCLK = 24.5 MHz.
•
•
•
•
•
Added a note linking to the Typical VOH and VOL Performance graphs in 4.1.14 Port I/O.
Added 4.1.11 1.8 V Internal LDO Voltage Regulator.
Added CRC Calculation Time to 4.1.4 Flash Memory.
Added specifications for 4.1.16 SMBus.
Added Thermal Resistance (Junction to Case) and Thermal Characterization Parameter (Junction to Top) for QFN20 and QFN28
packages to 4.2 Thermal Conditions.
• Updated 5.2 USB typical connections chapter to add a note and resistor divider for self-powered configurations.
• Corrected the application note number for AN124: Pin Sharing Techniques for the C2 Interface in 5.3 Debug.
• Adjusted D, E, and aaa in QFN28 Package Dimensions.
Revision 1.1
December 16, 2015
• Updated 3.2 Power to properly reflect that a comparator falling edge wakes the device from Suspend and Snooze.
• Added Note 4 to Table 4.1 Recommended Operating Conditions on page 16.
• Added 5.3 Debug.
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Rev. 1.3 | 62
EFM8UB1 Data Sheet
Revision History
Revision 1.0
• Updated any TBD numbers in 4.1 Electrical Characteristics and adjusted various specifications.
• Updated VOH and VOL graphs in Figure 4.7 Typical VOH Curves on page 34 and Figure 4.8 Typical VOL Curves on page 34 and
updated the VOH and VOL specifications in Table 4.14 Port I/O on page 26.
• Added more information to 3.10 Bootloader.
• Updated part numbers to Revision C.
Revision 0.3
• Updated QFN20 packaging and landing diagram dimensions.
• Updated QFN28 D and E minimum value.
• Updated some characterization TBD values.
• Added maximum allowable voltages on D+ and D- and added VBUS / P3.1 to the standard I/O row in Table 4.19 Absolute Maximum
Ratings on page 30.
• Added a diagram to 5.1 Power for cases when the internal 5 V-to-3.3 V regulator is not used.
• Updated the 5 V-to-3.3 V regulator Electrical Characteristics table.
• Added Stop mode to the Power Modes table in 3.2 Power.
Revision 0.2
• Initial release.
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Rev. 1.3 | 63
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trademarks of Silicon Labs. ARM, CORTEX, Cortex-M3 and THUMB are trademarks or registered trademarks of ARM Holdings. Keil is a registered trademark of ARM Limited. All
other products or brand names mentioned herein are trademarks of their respective holders.
Silicon Laboratories Inc.
400 West Cesar Chavez
Austin, TX 78701
USA
http://www.silabs.com