SLUSEJ1 Data sheet

SLUSEJ1A December 2021 – November 2023 TPSM8D6C24

PRODUCTION DATA

Package Options

Mechanical Data (Package|Pins)

MOW|59

Thermal pad, mechanical data (Package|Pins)

Orderable Information

6.6.53 (65h) TOFF_FALL

CMD Address	65h
Write Transaction:	Write Word
Read Transaction:	Read Word
Format:	SLINEAR11 per CAPABILITY
Phased:	No
NVM Backup:	EEPROM
Updates:	On-the-fly

The TOFF_FALL command sets the time, in milliseconds, from the end of the turn-off delay time until the voltage is commanded to 0. This command can only be used with a device whose output can sink enough current to cause the output voltage to decrease at a controlled rate, which effectively sets the slew rate of the reference DAC during the soft-off period. The fall time is equal to TOFF_FALL regardless of the value of the target output voltage or VOUT_SCALE_LOOP for the purposes of slew rate selection based on the target output voltage.

Figure 6-59 (65h) TOFF_FALL Register Map

15	14	13	12	11	10	9	8
RW	RW	RW	RW	RW	RW	RW	RW
TOFFF_EXP					TOFFF_MAN

7	6	5	4	3	2	1	0
RW	RW	RW	RW	RW	RW	RW	RW
TOFFF_MAN

LEGEND: R/W = Read/Write; R = Read only

Table 6-70 Register Field Descriptions

Bit	Field	Access	Reset	Description
15:11	TOFFF_ EXP	RW	11110b	Linear format two’s complement exponent. Exponent = -2, LSB = 0.25 ms
10:0	TOFFF_ MAN	RW	NVM	Linear format two’s complement mantissa

Attempts to write (65h) TOFF_FALL beyond the supported range are considered invalid or unsupported data and cause the TPSM8D6C24 to respond by flagging the appropriate status bits and notifying the host according to the PMBus 1.3.1 Part II specification section 10.9.3. (65h) TOFF_FALL supports values from 0.5 ms to 31.75 ms in 0.25-ms steps. Values less than 0.5 ms are implemented as 0.5 ms.

Due to hardware limitations in the resolution of the reference DAC slew-rate control, longer TOFF_FALL times with higher (21h) VOUT_COMMAND voltages can result in some quantization error in the programmed TOFF_FALL times with several TOFF_FALL times producing the same VOUT slope and TOFF_FALL time even with different TOFF_FALL settings, or different TOFF_FALL times for the same TOFF_FALL setting and different (21h) VOUT_COMMAND voltages.