...the world's most energy friendly microcontrollers EFM32LG942 Errata History F256/F128/F64 This document describes known errata for all revisions of EFM32LG942 devices. ...the world's most energy friendly microcontrollers 1 Errata History 1.1 Errata Overview Table 1.1 (p. 2) shows which erratum is applicable for each revision. The device datasheet explains how to identify chip revision, either from package marking or electronically. In addition to the errata noted below, the errata for the ARM Cortex-M3 r2p1 (www.arm.com) also applies to all revisions of this device. Table 1.1. Errata Overview Erratum ID Rev. Rev. E D Rev. Rev. C B ADC_E116 X ADC_E117 X X X AES_E101 X X X AES_E102 X X X BU_E101 X BU_E102 X BU_E104 X BU_E105 X X X X BU_E106 X BURTC_E101 X X X BURTC_E102 X X X CMU_E108 X CMU_E110 X CMU_E111 CMU_E112 X CMU_E113 X CMU_E114 X X X X X X 2014-06-13 - EFM32LG942FXX - d0223_Rev0.50 2 www.silabs.com ...the world's most energy friendly microcontrollers Erratum ID Rev. Rev. E D Rev. Rev. C B CUR_E103 X CUR_E104 X X DI_E102 X X X DMA_E101 X X X EMU_E105 X ETM_E101 X GPIO_E101 X LES_E101 X LES_E102 X LES_E103 X MSC_E101 X OPA_E101 X X PRS_E101 X X X USART_E112 X X X USB_E101 X USB_E102 X USB_E103 X X X X USB_E104 X X X X USB_E105 X X X X USB_E106 X USB_E107 X X USB_E108 X X USB_E109 X X X X USB_E110 X X X X 2014-06-13 - EFM32LG942FXX - d0223_Rev0.50 3 www.silabs.com ...the world's most energy friendly microcontrollers 1.2 EFM32LG942 Errata Descriptions Table 1.2. EFM32LG942 Errata Descriptions ID Title/Problem Effect Fix/Workaround ADC_E116 Offset in ADC Temperature Sensor Calibration DataData For devices with PROD_REV values of 16 or 17, the ADC0_TEMP_0_READ_1V25 register of the Device Information Page has an offset of 112. Using this value for calculating the absolute temperature gives an approximately 18 degrees too high value. Relative temperature measurements (temperature changes) are not affected by this offset. For devices with PROD_REV values of 16 or 17, use ADC0_TEMP_0_READ_1V25 - 112 instead of ADC0_TEMP_0_READ_1V25 when calculating the temperature. For ADC warm-up, the user is required to set the ADC_CTRL_TIMEBASE to the number of ADC clock cycles in 1 µs. As this register is only 5 bits wide, it does not support frequencies above 32 MHz. If an ADC clock above 32 MHz is required, the acquistion time should be increased to also account for too short warmup-time. If BYTEORDER is used in combination with DATASTART or XORSTART, the AES data and key are interpreted in the wrong order. Do not use BYTEORDER in combination with DATASTART or XORSTART. If BYTEORDER is used, it will take one cycle for the AES_STATUS_RUNNING flag to be set. This means that polling this status flag should be postponed at least one cycle after starting encryption/decryption. If polling the AES_STATUS_RUNNING is preferred, insert a No Operation assembly instruction (NOP()) before starting to poll the status flag. Additional current consumption on BU_VIN approximately 100uA when VDD_DREG is between 0.3 BU_VIN to 0.7 BU_VIN. Avoid having VDD_DREG in between 0.3 BU_VIN to 0.7 BU_VIN. The ADC temperature sensor calibration value stored in the Device Information (DI) Page has an offset. ADC_E117 TIMEBASE not wide enough For 48 MHz ADC clock, the ADC_CTRL_TIMEBASE is not wide enough. AES_E101 BYTEORDER does not work in combination with DATASTART/XORSTART When the BYTEORDER bit in AES_CTRL is set, an encryption or decryption should not be started through DATASTART or XORSTART. AES_E102 AES_STATUS_RUNNING set one cycle late with BYTEORDER set When the BYTEORDER bit in AES_CTRL is set, AES_STATUS_RUNNING is set one cycle late. BU_E101 Backup power increased power consumtion Additional current consumption on BU_VIN approximately 100uA when VDD_DREG is between 0.3 BU_VIN to 0.7 BU_VIN. 2014-06-13 - EFM32LG942FXX - d0223_Rev0.50 4 www.silabs.com ...the world's most energy friendly microcontrollers ID Title/Problem Effect Fix/Workaround BU_E102 EM4 GPIO retention in backup mode With GPIO retention enabled, GPIO pins will still drive in backup mode. Do not use EM4 GPIO retention in combination with backup mode. EM4 with backup BODs does not trigger reset. Avoid using backup BODs when entering EM4. When IOVDD is ramped, the DC-level of the XTAL signal changes, resulting in missed LFXO cycles and possible glitches on the LFXO clock. Set PRESC in BURTC_CTRL to greater then 0 when ramping IOVDD in combination with Backup mode to avoid glitches on the LFXO clock. EM4 GPIO retention not shut off in backup mode. BU_E104 EM4 with backup BODs EM4 with backup BODs does not trigger reset. BU_E105 LFXO missing cycles during IOVDD rampings LFXO missing cycles during IOVDD ramping when used in combination with Backup mode. BU_E106 Current leakage in Backup mode In Backup mode, when VDD > BU_VIN + 0.7, current will leak from VDD. To avoid leakage, exit Backup mode before VDD exceeds the voltage where the leakage start by configuring the threshold in EMU_BUACT. BURTC_E101 BURTC LPMODE entry Counting error occurs if overflow on 7 LSBs happens when entering LPMODE with LPCOMP=7. This results in the counter value being 256 less than it should be after the error. The error accumulates. Avoid using LPMODE with LPCOMP=7. When LPMODE is active (i.e. BURTC_STATUS_LPMODEACT is high), software reads might result in wrong value being read from BURTC_CNT. Before reading BURTC_CNT, disable LPMODE and wait for BURTC_STATUS_LPMODEACT to be cleared before reading BURTC_CNT. For devices with PROD_REV < 15, enabling the clock for LFA/LFB after reset and then immediately writing LFACLKEN/LFBCLKEN, may cause the write to miss its effect. For devices with PROD_REV < 15, make sure CMU_SYNCBUSY is not set before writing LFACLKEN/LFBCLKEN. Can temporarily switch to HFCORECLKLEDIV2 to speed up clearing synchbusy. Transients on pin D8 can give a temporary phase shift on LFXO. Frequency is unchanged. No known workaround. For devices with PROD_REV < 15, LFXOBUFCUR in CMU_CTRL is default 0 and LFXOBOOST in CMU_CTRL is default 1. However, these values are incorrect. On devices with PROD_REV < 15, change LFXOBUFCUR to 1 and LFXOBOOST to 0. Entering LPMODE with LPCOMP=7 causes counter error. BURTC_E102 BURTC_CNT read error Software reads from BURTC_CNT might fail when LPMODE is activated CMU_E108 LFxCLKEN write First write to LFxCLKEN can be missed. CMU_E110 LFXO phase shift Transients on pin D8 cause LFXO phase shift. CMU_E111 LFXO configuration incorrect LFXO configuration incorrect. 2014-06-13 - EFM32LG942FXX - d0223_Rev0.50 5 www.silabs.com ...the world's most energy friendly microcontrollers ID Title/Problem Effect Fix/Workaround CMU_E112 LFXO boost buffer current setting LFXO will not work properly with LFXOBUFCUR in CMU_CTRL set. Do not set LFXOBUFCUR in CMU_CTRL. For devices with PROD_REV = 16, LFXO may have startup issues with low capacitance crystals when using the default LFXO configuration. Make this line of code part of your starup code, typically in the start of main(): *((volatile uint32_t*) 0x400c80C0) = (*((volatile uint32_t*) 0x400c80C0) & ~(1<<6)) | (1<<4);. When the chip is running from any other prescaled oscillator than HFRCO as HFCLK and HFRCO disabled the chip will not wake-up from EM2. Before entering EM2, clear CMU_CTRL_HFCLKDIV or enable HFRCO by setting CMU_OSCENCMD_HFRCOEN and wait until CMU_STATUS_HFRCORDY is set. Current consumption in EM2 and EM3 has two stable states, the normal state (1200 nA and 900 nA for EM2 and EM3 respectively) and an error state. In the error state the current consumption in EM2 and EM3 is typically 4.5 uA at 25C (manufacturing test limits is set to 7 uA) but will increase with increased temperature. At 85C the error state EM2 and EM3 current consumption is typically 25 uA. It is unpredictable which state the device will go into on EM2/EM3 entry and it can also change state during operation. No known workaround. LFXO boost buffer current must be disabled CMU_E113 LFXO startup at high temperature LFXO does not start at high temperature with default configuration. CMU_E114 Chip not waking up from EM2 when using prescaled non-HFRCO oscillator as HFCLK Chip not waking up from EM2 when using prescaled non-HFRCO oscillator as HFCLK. CUR_E103 Increased EM2 current Increased consumption in EM2 CUR_E104 Increased current on AVDD2 When VREGO is floating or 0 V, a leakage can appear on AVDD2. This leakage is typically less than 10 uA, but can alIncreased current on AVDD2 related to so rise to around 300 uA. VREGO Make sure VREGO is always defined high when there is power on AVDD2. For bus-powered devices this is always the case, but for devices where the power on VREGO can be lost during operation, e.g. a USB device where the USB phy is powered from VBUS when a master is attached, a 5 MOhm to VDD can help keep VREGO defined. DI_E102 Flash Page Size For devices with PROD_REV values lower than 18, the MEM_INFO_PAGE_SIZE register value in the Device Information Page is incorrect. Use fixed flash page size of 2k bytes. In EM2, when sleeping with WFE (Wait for Event), an interrupt from the DMA will not wake up the system. Use WFI (Wait for Interrupt) or EM1 instead. The MEM_INFO_PAGE_SIZE value stored in Device Information (DI) Page is incorrect. DMA_E101 EM2 with WFE and DMA WFE does not work for the DMA in EM2. 2014-06-13 - EFM32LG942FXX - d0223_Rev0.50 6 www.silabs.com ...the world's most energy friendly microcontrollers ID Title/Problem Effect Fix/Workaround EMU_E105 Debug unavailable during DMA processing from EM2 DMA requests from the LEUART can trigger a DMA operation from EM2. While waiting for the DMA to fetch data from the respective peripheral, the debugger cannot access the system. If such a DMA request is not handled by the DMA controller, the system will keep waiting for it while denying debug access. Make sure DMA requests triggered from EM2 are handled. ETM trace clock is out of phase making the data transition occur at the same time as the ETM trace clock transitions. ETM trace clock needs to be delayed between 10 ns and 1/4 of the trace clock period. All EM4 wakeup cause bits for EM4 wakeup pins with high polarity are set on wakeup. Use low polarity if possible. For active high, slow changing inputs, a solution is to sample the inputs on wakeup. The debugger cannot access the system processing DMA request from EM2. ETM_E101 ETM Trace Clock ETM Trace Clock needs to be delayed. GPIO_E101 GPIO wakeup from EM4 On GPIO wakeup from EM4 all cause bits for high-polarity wakeup pins are set. LES_E101 LES_E102 LESENSE and Schmitt trigger Schmitt trigger cannot be disabled on pins used for sensor excitation When using LESENSE to excite a pin, the pin has to be con- Keep the input voltage to pins configured as push-pull outfigured in push-pull mode, which also enables the Schmitt side the range 0.3*VDD to 0.7*VDD when LESENSE is not trigger. If this pin has an input voltage somewhere in between interacting with the connected sensor. 0.3*VDD and 0.7*VDD, the Schmitt trigger will consume a considerable ammount of current. LESENSE and DAC CH1 configuration LESENSE control of DAC CH1 cannot be enabled if DACCH0CONV in LESENSE_PERCTRL is set to DISABLE. Configure DACCH0CONV in LESENSE_PERCTRL to anything but DISABLE, this enables DAC CH1 to be controlled properly. If DAC CH0 is not to be used, set DACCH0OUT in LESENSE_PERCTRL to DISABLE. This will disable LESENSE control of DAC CH0, but still allow LESENSE to control DAC CH1. LESENSE will not work properly when used with the AUXHFRCO running at the 1 or 7 MHz band. Do not use a AUXHFRCO frequency band of 1 or 7 MHz when used in combination with LESENSE. When prefetch is enabled, i.e. PREFETCH is set in MSC_READCTRL, wrong instruction data can be prefetched causing system failure. Do not use prefetch. When OPA2 is started the output rampup is constant independent of bias setting. No known workaround. LESENSE cannot control DAC CH1 if DACCH0CONV in LESENSE_PERCTRL is set to DISABLE. LES_E103 AUXHFRCO and LESENSE LESENSE will not work properly at low AUXHFRCO frequencies. MSC_E101 Prefetch unreliable Prefetch unreliable. OPA_E101 Opamp 2 startup rampup 2014-06-13 - EFM32LG942FXX - d0223_Rev0.50 7 www.silabs.com ...the world's most energy friendly microcontrollers ID Title/Problem Effect Fix/Workaround When using edge detect in PRS on signals from ACMP, GPIO, RTC, LETIMER, LESENSE, VCMP and BURTC edges can be missed. Do not use edge detect on ACMP, GPIO, RTC, LETIMER, LESENSE, VCMP and BURTC. When OPA2 is started the output rampup is constant independent of bias setting. PRS_E101 Edge detect on GPIO/ACMP Edge detect on peripherals with asynchronous edges might be missed. USART_E112 USART AUTOTX continues to transmit even with full RX buffer When AUTOTX in USARTn_CTRL or AUTOTXEN in USARTn_TRIGCTRL is set, the USART will continue to transmit data even after the RX buffer is full. This may cause USART AUTOTX continues to transmit the RX buffer to overflow if the data is not read out in time. even with full RX buffer. No known workaround. USB_E101 USB DMA transfers with prescaled HFCLK Do not prescale HFCLK when using USB-DMA transfers to read from flash. USB DMA transfers to flash may fail when prescaling HFCLK. USB DMA transfers to flash fail when prescaling HFCLK. USB_E102 USB datalines USB datalines rise and fall time are slightly outside specification. USB datalines rise and fall time are slightly outside specifica- No known workaround. tion under worst case conditions. They may fail USB certification eye test depending on PCB layout. USB_E103 HNP Sequence fails if A-Device con- The B-Device core waits for less amount of time (3.4ms) and nects after 3.4ms signals HNP fail and reverts back to Peripheral. HNP sequence fails if A-Device connects after 3.4ms. HNP Sequence fails if A-Device connects after 3.4ms. No known workaround. USB_E104 USB A-Device delays the HNP switch back process The A-Device core delays the HNP switch back process. As per the USB-OTG 2.0 specification, the B-Device on the other side of USB either should wait for disconnect from A-Device or should switch to Peripheral mode and wait for A-Device to issue reset. Hence, there is no significant impact on actual operation. No known workaround. If B-Device as Host on the other side of USB drives K-J pairs for more than 200ms during USB reset, the A-Device core exits peripheral state causing HNP process to fail. There is no significant impact since normally the host drives USB reset for lesser time than 200ms. No known workaround. Disconnecting the D+ lines only occur after 200ms, making the HNP switch back delayed. USB_E105 B-Device as Host driving K-J pairs during reset A-Device misinterprets the K-J pairs as Suspend, after switching to High Speed mode. 2014-06-13 - EFM32LG942FXX - d0223_Rev0.50 8 www.silabs.com ...the world's most energy friendly microcontrollers ID Title/Problem Effect Fix/Workaround USB_E106 USB interrupts USB inteerrupts are now trigggered by signal edge rather then signal level. Make sure to handle edge triggered interrupt, rather then signal level interrupts. On transition from EM0 to EM4 a current leakage from VREGO of up to 1 mA lasting a few seconds can occur. No known workaround. When the USB_DM or USB_DP pins are floating while the USB PHY is disabled, a current in the order of a couple hundred uA may leak from USB_VREGO to VSS. This will not be an issue if there is no voltage applied to USB_VREGO, either externally or through the USB regulator. If there is no intention to use the USB module, e.g. the USB PHY is disabled, but there is still a voltage on USB_VREGO, make sure the USB_DM and USB_DP pins are defined. This can be done using GPIO or by defining them externally. USB interrupts have changed from being level triggered to edge triggered. USB_E107 Entry to EM4 causes temporary leakage from VREGO Entry to EM4 causes temporary leakage from VREGO. USB_E108 Floating DM/DP pins cause leakage when USB is disabled Floating DM/DP pins cause leakage when USB is disabled. USB_E109 Missing GINTSTS.SessReq Interrupt When USB_PCGCCTL.STOPPCLK is set and the device is with USB_PCGCCTL.STOPPCLK = 1 acting as a B-peripheral, a Host-initated Suspend, followed by a Host Disconnect and Host Connect will not result in a A Host-initiated Suspend, followed by SessReq interrupt. a Host Disconnect and Host Connect will not result in a SessReq interrupt. USB_E110 Unexpected HCINTn.ChHltd interrupt In some cases the HCINTn.ChHltd interrupt might be wrongly set. 2014-06-13 - EFM32LG942FXX - d0223_Rev0.50 If this is an expected use-case, USB_PCGCCTL.STOPPCLK should not be set. USB_PCGCCTL.GATEHCLK can still be used to save power. In some cases an unexpected HCINTn.ChHltd interrupt might If such an interrupt is received, the application must rebe received from another endpoint from which it has not set enable the channel for which it received the unexpected the HCCHARn.CHDis, HCINTn.XactErr, HCINTn.BblErr, HCINTn.ChHltd interrupt. HCINTn.DataTglErr or HCINTn.XferComplete interrupt. 9 www.silabs.com ...the world's most energy friendly microcontrollers 2 Revision History 2.1 Revision 0.50 June 13th, 2014 Updated to product revision E. 2.2 Revision 0.40 August 21st, 2013 Added ADC_E117. Added AES_E102. Added USB_E109. Added USB_E110. Updated disclaimer, trademark and contact information. 2.3 Revision 0.30 July 30th, 2013 Added AES_E101. Added BURTC_E102. Added CMU_E114. Added DMA_E101. Updated errata naming convention. 2.4 Revision 0.20 June 5th, 2012 2014-06-13 - EFM32LG942FXX - d0223_Rev0.50 10 www.silabs.com ...the world's most energy friendly microcontrollers Added ADC1. Added DI1. 2.5 Revision 0.10 April 24th, 2012 Initial preliminary release. 2014-06-13 - EFM32LG942FXX - d0223_Rev0.50 11 www.silabs.com ...the world's most energy friendly microcontrollers A Disclaimer and Trademarks A.1 Disclaimer Silicon Laboratories intends to provide customers with the latest, accurate, and in-depth documentation of all peripherals and modules available for system and software implementers using or intending to use the Silicon Laboratories products. Characterization data, available modules and peripherals, memory sizes and memory addresses refer to each specific device, and "Typical" parameters provided can and do vary in different applications. Application examples described herein are for illustrative purposes only. Silicon Laboratories reserves the right to make changes without further notice and limitation to product information, specifications, and descriptions herein, and does not give warranties as to the accuracy or completeness of the included information. Silicon Laboratories shall have no liability for the consequences of use of the information supplied herein. This document does not imply or express copyright licenses granted hereunder to design or fabricate any integrated circuits. The products must not be used within any Life Support System without the specific written consent of Silicon Laboratories. A "Life Support System" is any product or system intended to support or sustain life and/or health, which, if it fails, can be reasonably expected to result in significant personal injury or death. Silicon Laboratories products are generally not intended for military applications. Silicon Laboratories products shall under no circumstances be used in weapons of mass destruction including (but not limited to) nuclear, biological or chemical weapons, or missiles capable of delivering such weapons. A.2 Trademark Information Silicon Laboratories Inc., Silicon Laboratories, Silicon Labs, SiLabs and the Silicon Labs logo, CMEMS®, EFM, EFM32, EFR, Energy Micro, Energy Micro logo and combinations thereof, "the world’s most energy friendly microcontrollers", Ember®, EZLink®, EZMac®, EZRadio®, EZRadioPRO®, DSPLL®, ISOmodem®, Precision32®, ProSLIC®, SiPHY®, USBXpress® and others are trademarks or registered trademarks of Silicon Laboratories Inc. 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. 2014-06-13 - EFM32LG942FXX - d0223_Rev0.50 12 www.silabs.com ...the world's most energy friendly microcontrollers B Contact Information Silicon Laboratories Inc. 400 West Cesar Chavez Austin, TX 78701 Please visit the Silicon Labs Technical Support web page: http://www.silabs.com/support/pages/contacttechnicalsupport.aspx and register to submit a technical support request. 2014-06-13 - EFM32LG942FXX - d0223_Rev0.50 13 www.silabs.com ...the world's most energy friendly microcontrollers Table of Contents 1. Errata History ............................................................................................................................................................................................................................. 2 1.1. Errata Overview ................................................................................................................................................................................................................ 2 1.2. EFM32LG942 Errata Descriptions ........................................................................................................................................................................................ 4 2. Revision History ........................................................................................................................................................................................................................ 10 2.1. Revision 0.50 ................................................................................................................................................................................................................. 10 2.2. Revision 0.40 ................................................................................................................................................................................................................. 10 2.3. Revision 0.30 ................................................................................................................................................................................................................. 10 2.4. Revision 0.20 ................................................................................................................................................................................................................. 10 2.5. Revision 0.10 ................................................................................................................................................................................................................. 11 A. Disclaimer and Trademarks ......................................................................................................................................................................................................... 12 A.1. Disclaimer ..................................................................................................................................................................................................................... 12 A.2. Trademark Information ..................................................................................................................................................................................................... 12 B. Contact Information ................................................................................................................................................................................................................... 13 B.1. ................................................................................................................................................................................................................................... 13 2014-06-13 - EFM32LG942FXX - d0223_Rev0.50 14 www.silabs.com ...the world's most energy friendly microcontrollers List of Tables 1.1. Errata Overview ........................................................................................................................................................................................................................ 2 1.2. EFM32LG942 Errata Descriptions ................................................................................................................................................................................................ 4 2014-06-13 - EFM32LG942FXX - d0223_Rev0.50 15 www.silabs.com