CY7B923 Cypress Semiconductor, CY7B923 Datasheet - Page 17

• Manufacturer Part Number: CY7B923
• Description: HOTLink Transmitter/Receiver
• Manufacturer: Cypress Semiconductor

BIST Mode
BIST mode functions as follows:
1. Set BISTEN LOW to begin test pattern generation. Trans-
2. Set either ENA or ENN LOW to begin pattern sequence
START
mitter begins sending bit rate ...1010...
generation (use of the Enable pin not being used for normal
FIFO or system interface can minimize logic delays be-
tween the controller and transmitter).
Tx
BEGIN
TEST
Rx
ERROR
START
TEST
LOOP
BIST
LOOP
BIST
Figure 7. Built In Self-Test Illustration
TEST
END
STOP
WITHIN SPEC.
WITHIN SPEC.
Tx
DON'T CARE
DON'T CARE
DON'T CARE
DON'T CARE
DON'T CARE
HIGH
LOW
LOW
17
8
8
Note: It may be advisable to send violation characters to test
the RVS output in the Receiver. This can be done by explicitly
sending a violation with the SVS input, or allowing the trans-
3. Allow the Transmitter to run through several BIST loops or
4. When testing is completed, set BISTEN HIGH and ENA and
until the Receiver test is complete. RP will pulse LOW once
per BIST loop, and can be used by an external counter to
monitor the number of test pattern loops.
ENN HIGH and resume normal function.
FOTO
MODE
CKW
RP
SC/D
D
SVS
ENA
ENN
BISTEN
REFCLK
MODE
RF
CKR
SC/D
Q
RVS
RDY
BISTEN
0
0
7
7
CY7B923
CY7B933
OUTC
OUTB
OUTA
INB
INA
A/B
SO
DON'T CARE
LOW
CY7B923
CY7B933
B923–23