SLLSF80 Data sheet

SLLSF80B October 2019 – March 2022 TCAN1144-Q1 , TCAN1145-Q1 , TCAN1146-Q1

PRODUCTION DATA

Package Options

Mechanical Data (Package|Pins)

DYY|14
- MPSS114C
DMT|14
- MPSS087B
D|14
- MPDS177H

Thermal pad, mechanical data (Package|Pins)

DMT|14
- QFND638

Orderable Information

10.4.7.7.4.3 WD Question and Answer Value Generation

The 4-bit WD question, WD_QA_QUESTION[3:0], is generated by 4-bit Markov chain process. A Markov chain is a stochastic process with Markov property, which means that state changes are probabilistic, and the future state depends only on the current state. The valid and complete WD answer sequence for each WD Q&A mode is as follows:

For WD Q&A multi-answer:
1. Three correct SPI WD answers are received during RESPONSE WINDOW 1.
2. One correct SPI WD answer is received during RESPONSE WINDOW 2.
3. In addition to the previously listed timing, the sequence of four responses shall be correct.

The WD question value is latched in the WD_QUESTION[3:0] bits of the WD_QA_QUESTION register and can be read out at any time.

The Markov chain process is clocked by the 4-bit Question counter at the transition from b1111 to b0000. This includes the condition of a correct answer (correct answer value and correct timing response). The logic combination of the 4-bit questions WD_QUESTION [3:0] generation is given in Figure 10-27.

If the current y value is 0000, the next y value is 0001. The next watchdog question generation process starts from that value.

Figure 10-27 Watchdog Question Generation

Table 10-12 contains the answers for each question, as long as the question polynomial and answer generation configuration are both at their default values.

Table 10-12 Example answers to questions with default settings

QUESTION IN WD_QUESTION_VALUE REGISTER	WD ANSWER BYTES (EACH BYTE TO BE WRITTEN INTO WD_QA_ANSWER REGISTER)
QUESTION IN WD_QUESTION_VALUE REGISTER	WD_ANSWER_RESP_3	WD_ANSWER_RESP_2	WD_ANSWER_RESP_1	WD_ANSWER_RESP_0
WD_QUESTION	WD_ANSW_CNT 2'b11	WD_ANSW_CNT 2'b10	WD_ANSW_CNT 2'b01	WD_ANSW_CNT 2'b00
0x0	FF	0F	F0	00
0x1	B0	40	BF	4F
0x2	E9	19	E6	16
0x3	A6	56	A9	59
0x4	75	85	7A	8A
0x5	3A	CA	35	C5
0x6	63	93	6C	9C
0x7	2C	DC	23	D3
0x8	D2	22	DD	2D
0x9	9D	6D	92	62
0xA	C4	34	CB	3B
0xB	8B	7B	84	74
0xC	58	A8	57	A7
0xD	17	E7	18	E8
0xE	4E	BE	41	B1
0xF	01	F1	0E	FE

Figure 10-28 WD Expected Answer Generation

Table 10-13 Correct and Incorrect WD Q&A Sequence Run Scenarios for WD Q&A Multi-Answer Mode (WD_CFG = 0b)

NUMBER OF WD ANSWERS		ACTION	WD STATUS BITS IN WD_QA_QUESTION REGISTER		COMMENTS
RESPONSE WINDOW 1	RESPONSE WINDOW 2	ACTION	QA_ANSW_ERR	WD_ERR⁽¹⁾	COMMENTS
0 answer	0 answer	-New WD cycle starts after the end of RESPONSE WINDOW 2 -Increment WD failure counter -New WD cycle starts with the same WD question	0b	1b	No answers
0 answer	4 INCORRECT answer	-New WD cycle starts after the 4th WD answer -Increment WD failure counter -New WD cycle starts with the same WD question	1b	1b	Total WD_ANSW_CNT[1:0] = 4
0 answer	4 CORRECT answer	-New WD cycle starts after the 4th WD answer -Increment WD failure counter -New WD cycle starts with the same WD question	0b	1b	Total WD_ANSW_CNT[1:0] = 4
0 answer	1 CORRECT answer	-New WD cycle starts after the end of RESPONSE WINDOW 2 -Increment WD failure counter -New WD cycle starts with the same WD question	0b	1b	Less than 3 CORRECT ANSWER in RESPONSE WINDOW 1 and 1 CORRECT ANSWER in RESPONSE WINDOW 2 (Total WD_ANSW_CNT[1:0] < 4)
1 CORRECT answer	1 CORRECT answer
2 CORRECT answer	1 CORRECT answer
0 answer	1 INCORRECT answer	-New WD cycle starts after the end of RESPONSE WINDOW 2 -Increment WD failure counter -New WD cycle starts with the same WD question	1b	1b	Less than 3 CORRECT ANSWER in RESPONSE WINDOW 1 and 1 INCORRECT ANSWER in RESPONSE WINDOW 2 (Total WD_ANSW_CNT[1:0] < 4)
1 CORRECT answer	1 INCORRECT answer
2 CORRECT answer	1 INCORRECT answer
0 answer	4 CORRECT answer	-New WD cycle starts after the 4th WD answer -Increment WD failure counter -New WD cycle starts with the same WD question	0b	1b	Less than 3 CORRECT ANSWER in WIN1 and more than 1 CORRECT ANSWER in RESPONSE WINDOW 2 (Total WD_ANSW_CNT[1:0] = 4)
1 CORRECT answer	3 CORRECT answer
2 CORRECT answer	2 CORRECT answer
0 answer	4 INCORRECT answer	-New WD cycle starts after the 4th WD answer -Increment WD failure counter -New WD cycle starts with the same WD question	1b	1b	Less than 3 CORRECT ANSWER in RESPONSE WINDOW 1 and more than 1 INCORRECT ANSWER in RESPONSE WINDOW 2 (Total WD_ANSW_CNT[1:0] = 4)
1 CORRECT answer	3 INCORRECT answer
2 CORRECT answer	2 INCORRECT answer
0 answer	3 CORRECT answer	-New WD cycle starts after the end of RESPONSE WINDOW 2 -Increment WD failure counter -New WD cycle starts with the same WD question	0b	1b	Less than 3 INCORRECT ANSWER in RESPONSE WINDOW 1 and more than 1 CORRECT ANSWER in RESPONSE WINDOW 2 (Total WD_ANSW_CNT[1:0] < 4)
1 INCORRECT answer	2 CORRECT answer	-New WD cycle starts after the end of RESPONSE WINDOW 2 -Increment WD failure counter -New WD cycle starts with the same WD question	1b	1b
2 INCORRECT answer	1 CORRECT answer		1b	1b
0 answer	3 INCORRECT answer	-New WD cycle starts after the end of RESPONSE WINDOW 2 -Increment WD failure counter -New WD cycle starts with the same WD question	1b	1b	Less than 3 INCORRECT ANSWER in RESPONSE WINDOW 1 and more than 1 INCORRECT ANSWER in RESPONSE WINDOW 2 (Total WD_ANSW_CNT[1:0] < 4)
1 INCORRECT answer	2 INCORRECT answer
2 INCORRECT answer	1 INCORRECT answer
0 answer	4 CORRECT answer	-New WD cycle starts after the 4th WD answer -Increment WD failure counter -New WD cycle starts with the same WD question	0b	1b	Less than 3 INCORRECT ANSWER in RESPONSE WINDOW 1 and more than 1 CORRECT ANSWER in RESPONSE WINDOW 2 (Total WD_ANSW_CNT[1:0] = 4)
1 INCORRECT answer	3 CORRECT answer		1b	1b
2 INCORRECT answer	2 CORRECT answer		1b	1b
0 answer	4 INCORRECT answer	-New WD cycle starts after the 4th WD answer -Increment WD failure counter -New WD cycle starts with the same WD question	1b	1b	Less than 3 INCORRECT ANSWER in RESPONSE WINDOW 1 and more than 1 INCORRECT ANSWER in RESPONSE WINDOW 2 (Total WD_ANSW_CNT[1:0] = 4)
1 INCORRECT answer	3 INCORRECT answer
2 INCORRECT answer	2 INCORRECT answer
3 CORRECT answer	0 answer	-New WD cycle starts after the end of RESPONSE WINDOW 2 -Increment WD failure counter -New WD cycle starts with the same WD Question	0b	1b	Less than 4 CORRECT ANSW in RESPONSE WINDOW 1 and more than 0 ANSWER in RESPONSE WINDOW 2 (Total WD_ANSW_CNT[1:0] < 4)
2 CORRECT answer	0 answer		0b	1b
1 CORRECT answer	0 answer		0b	1b
3 CORRECT answer	1 CORRECT answer	-New WD cycle starts after the 4th WD answer -Decrement WD failure counter -New WD cycle starts with a new WD question	0b	0b	CORRECT SEQUENCE
3 CORRECT answer	1 INCORRECT answer	-New WD cycle starts after the 4th WD answer -Increment WD failure counter -New WD cycle starts with the same WD question	1b	1b	Total WD_ANSW_CNT[1:0] = 4
3 INCORRECT answer	0 answer	-New WD cycle starts after the end of RESPONSE WINDOW 2 -Increment WD failure counter -New WD cycle starts with the same WD question	1b	1b	Total WD_ANSW_CNT[1:0] < 4
3 INCORRECT answer	1 CORRECT answer	-New WD cycle starts after the 4th WD answer -Increment WD failure counter -New WD cycle starts with the same WD question	1b	1b	Total WD_ANSW_CNT[1:0] = 4
3 INCORRECT answer	1 INCORRECT answer	-New WD cycle starts after the 4th WD answer -Increment WD failure counter -New WD cycle starts with the same WD question	1b	1b	Total WD_ANSW_CNT[1:0] = 4
4 CORRECT answer	Not applicable	-New WD cycle starts after the 4th WD answer -Increment WD failure counter -New WD cycle starts with the same WD question	0b	1b
3 CORRECT answer + 1 INCORRECT answer	Not applicable	-New WD cycle starts after the 4th WD answer -Increment WD failure counter -New WD cycle starts with the same WD question	1b	1b	4 CORRECT or INCORRECT ANSWER in RESPONSE WINDOW 1
2 CORRECT answer + 2 INCORRECT answer	Not applicable
1 CORRECT answer + 3 INCORRECT answer	Not applicable

(1) WD_ERR is the logical OR of all WD errors.