TPS6594-Q1: Power up fail at low temp

Ryan Wang

Expert 6540 points

Part Number: TPS6594-Q1

Dear expert,

Customer use TPS65941213 + LP876411B4RQKRQ1.

There is one pcs system cannot power up at -20C. Need your guidance here:

Below is TPS6594 VCCA_3V3 and Buck3 output. After several retry fail, they shut down VCCA_3V3.

Below is TPS6594 and Buck3 output zoom in.

Below is TPS6594 VCCA_3V3 and LDO

Below is TPS6594 VCCA_3V3 and LDO zoom in:

Below is LP8764 Vout and GPIO 10 output

Below is TPS6594 register dump:

DEV_REV

0x01

NVM_CODE_1

0x02

NVM_CODE_2

0x03

BUCK1_CTRL

0x04

BUCK1_CONF

0x05

BUCK2_CTRL

0x06

BUCK2_CONF

0x07

BUCK3_CTRL

0x08

BUCK3_CONF

0x09

BUCK4_CTRL

0x0A

BUCK4_CONF

0x0B

BUCK5_CTRL

0x0C

BUCK5_CONF

0x0D

BUCK1_VOUT_1

0x0E

BUCK1_VOUT_2

0x0F

BUCK2_VOUT_1

0x10

BUCK2_VOUT_2

0x11

BUCK3_VOUT_1

0x12

BUCK3_VOUT_2

0x13

BUCK4_VOUT_1

0x14

BUCK4_VOUT_2

0x15

BUCK5_VOUT_1

0x16

BUCK5_VOUT_2

0x17

BUCK1_PG_WINDOW

0x18

BUCK2_PG_WINDOW

0x19

BUCK3_PG_WINDOW

0x1A

BUCK4_PG_WINDOW

0x1B

BUCK5_PG_WINDOW

0x1C

LDO1_CTRL

0x1D

LDO2_CTRL

0x1E

LDO3_CTRL

0x1F

LDO4_CTRL

0x20

LDOINT_CTRL

0x21

LDORTC_CTRL

0x22

LDO1_VOUT

0x23

LDO2_VOUT

0x24

LDO3_VOUT

0x25

LDO4_VOUT

0x26

LDO1_PG_WINDOW

0x27

LDO2_PG_WINDOW

0x28

LDO3_PG_WINDOW

0x29

LDO4_PG_WINDOW

0x2A

VCCA_VMON_CTRL

0x2B

VCCA_PG_WINDOW

0x2C

GPIO1_CONF

0x31

GPIO2_CONF

0x32

GPIO3_CONF

0x33

GPIO4_CONF

0x34

GPIO5_CONF

0x35

GPIO6_CONF

0x36

GPIO7_CONF

0x37

GPIO8_CONF

0x38

GPIO9_CONF

0x39

GPIO10_CONF

0x3A

GPIO11_CONF

0x3B

NPWRON_CONF

0x3C

GPIO_OUT_1

0x3D

GPIO_OUT_2

0x3E

GPIO_IN_1

0x3F

GPIO_IN_2

0x40

RAIL_SEL_1

0x41

RAIL_SEL_2

0x42

RAIL_SEL_3

0x43

FSM_TRIG_SEL_1

0x44

FSM_TRIG_SEL_2

0x45

FSM_TRIG_MASK_1

0x46

FSM_TRIG_MASK_2

0x47

FSM_TRIG_MASK_3

0x48

MASK_BUCK1_2

0x49

MASK_BUCK3_4

0x4A

MASK_BUCK5

0x4B

MASK_LDO1_2

0x4C

MASK_LDO3_4

0x4D

MASK_VMON

0x4E

MASK_GPIO1_8_FALL

0x4F

MASK_GPIO1_8_RISE

0x50

MASK_GPIO9_11

0x51

MASK_STARTUP

0x52

MASK_MISC

0x53

MASK_MODERATE_ERR

0x54

MASK_FSM_ERR

0x56

MASK_COMM_ERR

0x57

MASK_READBACK_ERR

0x58

MASK_ESM

0x59

INT_TOP

0x5A

INT_BUCK

0x5B

INT_BUCK1_2

0x5C

INT_BUCK3_4

0x5D

INT_BUCK5

0x5E

INT_LDO_VMON

0x5F

INT_LDO1_2

0x60

INT_LDO3_4

0x61

INT_VMON

0x62

INT_GPIO

0x63

INT_GPIO1_8

0x64

INT_STARTUP

0x65

INT_MISC

0x66

INT_MODERATE_ERR

0x67

INT_SEVERE_ERR

0x68

INT_FSM_ERR

0x69

INT_COMM_ERR

0x6A

INT_READBACK_ERR

0x6B

INT_ESM

0x6C

STAT_BUCK1_2

0x6D

STAT_BUCK3_4

0x6E

STAT_BUCK5

0x6F

STAT_LDO1_2

0x70

STAT_LDO3_4

0x71

STAT_VMON

0x72

STAT_STARTUP

0x73

STAT_MISC

0x74

STAT_MODERATE_ERR

0x75

STAT_SEVERE_ERR

0x76

STAT_READBACK_ERR

0x77

PGOOD_SEL_1

0x78

PGOOD_SEL_2

0x79

PGOOD_SEL_3

0x7A

PGOOD_SEL_4

0x7B

PLL_CTRL

0x7C

CONFIG_1

0x7D

CONFIG_2

0x7E

ENABLE_DRV_REG

0x80

MISC_CTRL

0x81

ENABLE_DRV_STAT

0x82

RECOV_CNT_REG_1

0x83

RECOV_CNT_REG_2

0x84

FSM_I2C_TRIGGERS

0x85

FSM_NSLEEP_TRIGGERS

0x86

BUCK_RESET_REG

0x87

SPREAD_SPECTRUM_1

0x88

FREQ_SEL

0x8A

FSM_STEP_SIZE

0x8B

LDO_RV_TIMEOUT_REG_1

0x8C

LDO_RV_TIMEOUT_REG_2

0x8D

USER_SPARE_REGS

0x8E

ESM_MCU_START_REG

0x8F

ESM_MCU_DELAY1_REG

0x90

ESM_MCU_DELAY2_REG

0x91

ESM_MCU_MODE_CFG

0x92

ESM_MCU_HMAX_REG

0x93

ESM_MCU_HMIN_REG

0x94

ESM_MCU_LMAX_REG

0x95

ESM_MCU_LMIN_REG

0x96

ESM_MCU_ERR_CNT_REG

0x97

ESM_SOC_START_REG

0x98

ESM_SOC_DELAY1_REG

0x99

ESM_SOC_DELAY2_REG

0x9A

ESM_SOC_MODE_CFG

0x9B

ESM_SOC_HMAX_REG

0x9C

ESM_SOC_HMIN_REG

0x9D

ESM_SOC_LMAX_REG

0x9E

ESM_SOC_LMIN_REG

0x9F

ESM_SOC_ERR_CNT_REG

0xA0

REGISTER_LOCK

0xA1

USER_EE_CTRL_1

0xA2

USER_EE_CTRL_2

0xA3

SRAM_ADDR_CTRL

0xA4

RECOV_CNT_PFSM_INCR

0xA5

MANUFACTURING_VER

0xA6

CUSTOMER_NVM_ID_REG

0xA7

SOFT_REBOOT_REG

0xAB

RTC_SECONDS

0xB5

RTC_MINUTES

0xB6

RTC_HOURS

0xB7

RTC_DAYS

0xB8

RTC_MONTHS

0xB9

RTC_YEARS

0xBA

RTC_WEEKS

0xBB

ALARM_SECONDS

0xBC

ALARM_MINUTES

0xBD

ALARM_HOURS

0xBE

ALARM_DAYS

0xBF

ALARM_MONTHS

0xC0

ALARM_YEARS

0xC1

RTC_CTRL_1

0xC2

RTC_CTRL_2

0xC3

RTC_STATUS

0xC4

RTC_INTERRUPTS

0xC5

RTC_COMP_LSB

0xC6

RTC_COMP_MSB

0xC7

RTC_RESET_STATUS

0xC8

SCRATCH_PAD_REG_1

0xC9

SCRATCH_PAD_REG_2

0xCA

SCRATCH_PAD_REG_3

0xCB

SCRATCH_PAD_REG_4

0xCC

PFSM_DELAY_REG_1

0xCD

PFSM_DELAY_REG_2

0xCE

PFSM_DELAY_REG_3

0xCF

PFSM_DELAY_REG_4

0xD0

RTS_SPARE_REG

0xD1

CRC_CALC_CONTROL

0xEF

CRC_1

0xF0

CRC_2

0xF1

CRC_3

0xF2

CRC_4

0xF3

CRC_5

0xF4

CRC_6

0xF5

CRC_7

0xF6

CRC_8

0xF7

CRC_9

0xF8

CRC_10

0xF9

CRC_11

0xFA

CRC_12

0xFB

CRC_15

0xFE

CRC_16

0xFF

WD_ANSWER_REG

0x01

WD_QUESTION_ANSW_CNT

0x02

WD_WIN1_CFG

0x03

WD_WIN2_CFG

0x04

WD_LONGWIN_CFG

0x05

WD_MODE_REG

0x06

WD_QA_CFG

0x07

WD_ERR_STATUS

0x08

WD_THR_CFG

0x09

WD_FAIL_CNT_REG

0x0A

Below is LP8764 register dump:

NVM_CODE_1	0x02	1	0	1	1	0	1	0	0
NVM_CODE_2	0x03	0	0	0	0	0	0	0	0
BUCK1_CTRL	0x04	0	0	1	0	0	0	0	0
BUCK1_CONF	0x05	0	0	1	0	1	0	1	1
BUCK2_CTRL	0x06	0	0	1	0	0	0	0	0
BUCK2_CONF	0x07	0	0	1	0	1	0	1	1
BUCK3_CTRL	0x08	0	0	1	0	0	0	0	0
BUCK3_CONF	0x09	0	0	1	0	0	0	1	0
BUCK4_CTRL	0x0A	0	0	1	0	0	0	0	0
BUCK4_CONF	0x0B	0	0	1	0	0	0	1	0
BUCK1_VOUT_1	0x0E	0	0	1	1	0	1	1	1
BUCK1_VOUT_2	0x0F	0	0	1	1	0	1	1	1
BUCK2_VOUT_1	0x10	0	0	1	1	0	1	1	1
BUCK2_VOUT_2	0x11	0	0	1	1	0	1	1	1
BUCK3_VOUT_1	0x12	0	0	0	0	0	0	0	0
BUCK3_VOUT_2	0x13	0	0	0	0	0	0	0	0
BUCK4_VOUT_1	0x14	0	0	0	0	0	0	0	0
BUCK4_VOUT_2	0x15	0	0	0	0	0	0	0	0
BUCK1_PG_WINDOW	0x18	0	0	0	1	1	0	1	1
BUCK2_PG_WINDOW	0x19	0	0	0	1	1	0	1	1
BUCK3_PG_WINDOW	0x1A	0	0	0	0	0	0	0	0
BUCK4_PG_WINDOW	0x1B	0	0	0	0	0	0	0	0
LDOINT_CTRL	0x21	0	0	0	0	0	0	0	0
VCCA_VMON_CTRL	0x2B	0	0	1	0	0	0	0	1
VCCA_PG_WINDOW	0x2C	0	0	1	1	1	1	1	1
VMON1_PG_WINDOW	0x2D	0	0	0	0	0	0	0	0
VMON1_PG_LEVEL	0x2E	0	0	0	0	0	0	0	0
VMON2_PG_WINDOW	0x2F	0	0	0	0	0	0	0	0
VMON2_PG_LEVEL	0x30	0	0	0	0	0	0	0	0
GPIO1_CONF	0x31	0	0	0	0	0	0	0	1
GPIO2_CONF	0x32	0	0	0	0	0	0	1	1
GPIO3_CONF	0x33	0	0	0	1	1	0	0	0
GPIO4_CONF	0x34	0	0	0	1	1	0	0	0
GPIO5_CONF	0x35	0	0	0	1	1	0	0	0
GPIO6_CONF	0x36	0	0	0	1	1	0	0	0
GPIO7_CONF	0x37	0	0	0	1	1	0	0	0
GPIO8_CONF	0x38	0	0	1	0	0	0	0	0
GPIO9_CONF	0x39	0	0	1	0	0	0	0	0
GPIO10_CONF	0x3A	0	0	0	0	0	0	0	1
ENABLE_CONF	0x3C	0	0	0	0	0	0	0	0
GPIO_OUT_1	0x3D	0	0	0	0	0	0	0	0
GPIO_OUT_2	0x3E	0	0	0	0	0	0	0	0
GPIO_IN_1	0x3F	0	0	0	0	0	0	0	0
GPIO_IN_2	0x40	0	0	0	0	0	0	0	0
RAIL_SEL_1	0x41	0	0	0	0	1	0	1	0
RAIL_SEL_3	0x43	0	0	0	0	0	1	0	0
FSM_TRIG_SEL_1	0x44	0	0	0	1	1	1	1	0
FSM_TRIG_SEL_2	0x45	0	0	0	0	0	0	0	1
FSM_TRIG_MASK_1	0x46	0	1	0	1	0	1	0	1
FSM_TRIG_MASK_2	0x47	0	1	0	1	0	1	0	1
FSM_TRIG_MASK_3	0x48	0	0	0	0	0	1	0	1
MASK_BUCK1_2	0x49	0	0	0	0	0	0	0	0
MASK_BUCK3_4	0x4A	0	0	0	0	0	0	0	0
MASK_BUCK3_4	0x4A	0	0	0	0	0	0	0	0
MASK_VMON	0x4E	0	1	1	0	1	1	0	0
MASK_GPIO1_8_FALL	0x4F	1	1	1	1	1	1	1	1
MASK_GPIO1_8_RISE	0x50	1	1	1	1	1	1	1	1
MASK_GPIO9_10	0x51	0	0	0	1	1	0	1	1
MASK_STARTUP	0x52	0	0	0	1	0	0	1	0
MASK_MISC	0x53	0	0	0	0	0	0	1	0
MASK_MODERATE_ERR	0x54	1	0	0	0	0	0	0	0
MASK_FSM_ERR	0x56	1	0	0	0	0	0	0	0
MASK_COMM_ERR	0x57	1	0	1	0	0	0	0	0
MASK_READBACK_ERR	0x58	0	0	0	0	1	0	0	1
MASK_ESM	0x59	0	0	1	1	1	0	0	0
INT_TOP	0x5A	1	0	1	1	0	0	0	0
INT_BUCK	0x5B	0	0	0	0	0	0	0	0
INT_BUCK1_2	0x5C	0	0	0	0	0	0	0	0
INT_BUCK3_4	0x5D	0	0	0	0	0	0	0	0
INT_VMON	0x62	0	0	0	0	0	0	0	0
INT_GPIO	0x63	0	0	0	0	0	0	0	0
INT_GPIO1_8	0x64	0	0	0	0	0	0	0	0
INT_STARTUP	0x65	0	0	0	0	0	0	0	0
INT_MISC	0x66	0	0	0	0	0	0	0	1
INT_MODERATE_ERR	0x67	0	0	0	0	1	0	0	0
INT_SEVERE_ERR	0x68	0	0	0	0	0	0	0	0
INT_FSM_ERR	0x69	0	0	0	0	0	0	1	0
INT_COMM_ERR	0x6A	0	0	0	0	0	0	0	0
INT_READBACK_ERR	0x6B	0	0	0	0	0	0	0	0
INT_ESM	0x6C	0	0	0	0	0	0	0	0
STAT_BUCK1_2	0x6D	0	0	0	0	0	0	0	0
STAT_BUCK3_4	0x6E	0	0	0	0	0	0	0	0
STAT_VMON	0x72	0	0	0	0	0	0	0	0
STAT_STARTUP	0x73	0	0	0	0	0	0	0	0
STAT_MISC	0x74	0	0	0	0	0	0	0	0
STAT_MODERATE_ERR	0x75	0	0	0	0	0	0	0	0
STAT_SEVERE_ERR	0x76	0	0	0	0	0	0	0	0
STAT_READBACK_ERR	0x77	0	0	0	0	0	0	0	0
PGOOD_SEL_1	0x78	0	0	0	0	0	0	0	0
PGOOD_SEL_4	0x7B	0	0	0	0	0	0	0	0
PLL_CTRL	0x7C	0	0	0	0	0	0	0	0
CONFIG_1	0x7D	1	1	0	0	0	0	0	0
ENABLE_DRV_REG	0x80	0	0	0	0	0	0	0	0
MISC_CTRL	0x81	0	0	0	0	0	1	0	0
ENABLE_DRV_STAT	0x82	0	0	0	1	1	0	0	0
RECOV_CNT_REG_1	0x83	0	0	0	0	1	1	1	1
RECOV_CNT_REG_2	0x84	0	0	0	0	1	1	1	1
FSM_I2C_TRIGGERS	0x85	0	0	0	0	0	0	0	0
FSM_NSLEEP_TRIGGERS	0x86	0	0	0	0	0	0	0	0
BUCK_RESET_REG	0x87	0	0	0	0	1	1	1	1
SPREAD_SPECTRUM_1	0x88	0	0	0	0	0	0	0	0
FREQ_SEL	0x8A	0	0	0	0	0	0	0	0
FSM_STEP_SIZE	0x8B	0	0	0	0	1	0	1	1
USER_SPARE_REGS	0x8E	0	0	0	0	0	0	0	0
ESM_MCU_START_REG	0x8F	0	0	0	0	0	0	0	0
ESM_MCU_DELAY1_REG	0x90	0	0	0	0	0	0	0	0
ESM_MCU_DELAY2_REG	0x91	0	0	0	0	0	0	0	0
ESM_MCU_MODE_CFG	0x92	0	0	0	0	0	0	0	0
ESM_MCU_HMAX_REG	0x93	0	0	0	0	0	0	0	0
ESM_MCU_HMIN_REG	0x94	0	0	0	0	0	0	0	0
ESM_MCU_LMAX_REG	0x95	0	0	0	0	0	0	0	0
ESM_MCU_LMIN_REG	0x96	0	0	0	0	0	0	0	0
ESM_MCU_ERR_CNT_REG	0x97	0	0	0	0	0	0	0	0
REGISTER_LOCK	0xA1	0	0	0	0	0	0	0	0
USER_EE_CTRL_1	0xA2	0	0	0	0	0	0	0	0
USER_EE_CTRL_2	0xA3	1	0	0	0	0	0	0	0
SRAM_ADDR_CTRL	0xA4	0	0	0	0	0	0	0	0
RECOV_CNT_PFSM_INCR	0xA5	0	0	0	0	0	0	0	0
MANUFACTURING_VER	0xA6	0	0	0	0	1	0	0	0
CUSTOMER_NVM_ID_REG	0xA7	0	0	0	0	0	0	0	0
VMON_CONF	0xA8	0	0	0	0	0	0	0	0
INT_SPI_STATUS	0xA9	0	0	0	0	0	0	0	0
SOFT_REBOOT_REG	0xAB	0	0	0	0	0	0	0	0
STARTUP_CTRL	0xC3	1	1	1	0	0	0	0	0
SCRATCH_PAD_REG_1	0xC9	0	0	0	0	0	0	0	0
SCRATCH_PAD_REG_2	0xCA	0	0	0	0	0	0	0	0
SCRATCH_PAD_REG_3	0xCB	0	0	0	0	0	0	0	0
SCRATCH_PAD_REG_4	0xCC	0	0	0	0	0	0	0	0
PFSM_DELAY_REG_1	0xCD	0	0	0	0	0	0	0	0
PFSM_DELAY_REG_2	0xCE	0	0	0	1	1	1	0	1
PFSM_DELAY_REG_3	0xCF	0	0	0	0	0	0	0	0
PFSM_DELAY_REG_4	0xD0	0	0	0	0	0	0	0	0
CRC_CALC_CONTROL	0xEF	0	0	0	0	0	0	0	0
CRC_1	0xF0	0	1	0	0	1	1	0	1
CRC_2	0xF1	0	0	0	0	1	0	1	0
CRC_3	0xF2	0	1	0	1	1	0	1	0
CRC_4	0xF3	1	1	0	0	0	1	0	1
CRC_5	0xF4	1	1	0	0	1	0	0	0
CRC_6	0xF5	0	1	1	1	0	0	0	0
CRC_7	0xF6	1	0	0	0	1	1	1	1
CRC_8	0xF7	0	0	1	0	1	0	1	1
CRC_9	0xF8	1	1	1	1	1	1	1	0
CRC_10	0xF9	0	0	0	1	0	0	0	0
CRC_15	0xFE	0	1	0	0	1	0	0	0
CRC_16	0xFF	1	0	0	1	0	1	1	0
WD_ANSWER_REG	0x01	0	0	0	0	0	0	0	0
WD_QUESTION_ANSW_CNT	0x02	0	0	1	1	1	1	0	0
WD_WIN1_CFG	0x03	0	1	1	1	1	1	1	1
WD_WIN2_CFG	0x04	0	1	1	1	1	1	1	1
WD_LONGWIN_CFG	0x05	0	0	0	0	0	0	0	0
WD_MODE_REG	0x06	0	0	0	0	0	0	1	0
WD_QA_CFG	0x07	0	0	0	0	1	0	1	0
WD_ERR_STATUS	0x08	0	0	0	0	0	0	0	0
WD_THR_CFG	0x09	1	0	1	1	1	1	1	1
WD_FAIL_CNT_REG	0x0A	0	0	1	0	0	0	0	0

7 months ago

0 Michael Gambrill 7 months ago

TI__Mastermind 21625 points

Hello Ryan,

The register dump reads out an interrupt for BUCK3_UV and LDO1_SC on the TPS65941213.

In your design is FB_B3 connected to VCCA?

Can you provide zoomed in scope shot to see if VCCA drops at during the recovery attempts?

How low does LDO1 drop to between each recovery attempt?

0 Ryan Wang 6 months ago in reply to Michael Gambrill

TI__Expert 6540 points

Michael,

Sorry for late response. Customer did some test.

Yes, FB_B3 connect to VCCA.

There is some small drop for VCCA.

Below is zoom in. You can see min voltage is 3.06V which doesn't reach VCCA_UV_THR（-10%）2.97V.

And we measured a good board for comparison.

Below is zoom in. Min is 3.0V

And customer optimized VCCA voltage drop from 3.06V to 3.17V for bad board. But there is still the same phenomenon.

Is there any suggestion?

For LDO1_SC interrupt, I think it is might due to LDO Residual Voltage Checking for several times reboot in the experiments. Do you think so?

Thanks

0 Michael Gambrill 6 months ago in reply to Ryan Wang

TI__Mastermind 21625 points

How confident are you in the accuracy of the o-scope? The VCCA_UV_THR is -9% to -11%, with -10% being the typical value for the setting. That means I expect the interupt to trigger between 2.937 to 3.003V. The deglitch is enabled, so it has to be below threshold for 20us.

Can you use a bench top 3.3V power supply instead of the your on-board 3.3V regulator? Then control the voltage level to see when VCCA_UV triggers.

0 Lijia Zhu 5 months ago in reply to Michael Gambrill

TI__Expert 4850 points

Hi Michael,

Long time no talk, hope you are doing well! Rayn is OOO and I will help to follow this issue.

I think it should be a device issue and I suggest letting customer ABA test for the next step. My analysis is below. Please correct me if you have more ideas.

1. Customer use an external power 3.3V supply instead of the on-board pre-regulator. Issue is reproduced too.

According to the scope shot, the 3.3V has some drop and the min voltage is 3.13V. It is higher than the UV threshold.

2. According to the PDN, BUCK3 monitor is enabled at 3.7ms after the GPIO9/10 rise. But the scope shot shows the power off happens about 8ms after that. I think UV detection does not need 8ms delay. There should some error internal the chip.

B&R

Lijia

0 Michael Gambrill 5 months ago in reply to Lijia Zhu

TI__Mastermind 21625 points

Lijia Zhu said:
2. According to the PDN, BUCK3 monitor is enabled at 3.7ms after the GPIO9/10 rise. But the scope shot shows the power off happens about 8ms after that. I think UV detection does not need 8ms delay. There should some error internal the chip.

That green channel in the scope shot shot does not show what is measured/monitored by FB_B3. Considering that it is 200mV/div and the speed that it ramps up and down, I think that is LDO3. LDO3 turns on at the 2.7ms mark of the TO_ACTIVE sequence and shuts down at the 2.5ms mark of the orderly shutdown sequence. Therefore, this scope capture doesn't show when PMIC saw the UV event.

Lijia Zhu said:
1. Customer use an external power 3.3V supply instead of the on-board pre-regulator. Issue is reproduced too.

According to the scope shot, the 3.3V has some drop and the min voltage is 3.13V. It is higher than the UV threshold

Please follow these experiment steps:

Supply board with 3.36V to allow PMICs to power up.
Clear interrupts on PMIC associated with start up.
Place scope probe on nINT and nRSTOUT of TPS65941213. They should both be HIGH at this point.
Slowly step down the VCCA supply in 5mV - 10mV steps until nINT and nRSTOUT both go low.
Measure DC voltage of VCCA at this point.

0 Lijia Zhu 5 months ago in reply to Michael Gambrill

TI__Expert 4850 points

Hi Michael,

Customer ABA the device and the failure follows the device. The failed device is returned to TI.

B&R

Lijia

Because of the holidays, TI E2E™ design support forum responses will be delayed from Dec. 25 through Jan. 2. Thank you for your patience.

Power management

Power management forum

TPS6594-Q1: Power up fail at low temp