MAX1455 Datasheet, PDF (18/25 Pages) Maxim Integrated Products – Low-Cost Automotive Sensor Signal Conditioner

Low-Cost Automotive Sensor Signal
Conditioner
Example 2. Read the lookup table pointer (Temp-
Index).
COMMAND
78hex
59hex
ACTION
Load 7 to IRSP[3:0] register.
Read IRS.
Host ready to receive data within 1 byte time
of sending the Read IRS command. The
MAX1455 returns the current Temp-Index
pointer value.
Example 4. Write 8C40hex to the FSODAC register.
COMMAND
00hex
41hex
C2hex
83hex
36hex
09hex
ACTION
Load 0 hex to the DHR[3:0] register.
Load 4 hex to the DHR[7:4] register.
Load C hex to the DHR[11:8] register.
Load 8 hex to the DHR[15:12] register.
Load 3 (FSODAC) to the ICRA[3:0] register.
Ld ICR.
8C40 hex is written to the FSODAC register.
Example 3. Enable BDR measurement on OUT pin for
3.4s duration with 9600 baud rate.
COMMAND
1Bhex
CAhex
69hex
ACTION
Load 1 (BDR measurement) to ALOC[3:0]
register.
Load 12 to the ATIM[3:0] register: (2¹²+1) ✕
8/9600 = 3.4s.
RdAlg.
The DIO pin is three-stated and the OUT pin
is connected internally to the BDR pin for a
duration of approximately 3.4s.
Example 5. Write 8C40hex to the FSODAC lookup
table location at Temp-Index 40. This example uses
the Page Erase command to clear the relevant section
of the EEPROM and assumes that none of the existing
data in that section is required to be kept.
COMMAND
A6hex
79hex
06hex
87hex
28hex
00hex
41hex
19hex
16hex
C0hex
81hex
19hex
ACTION
Load Ahex (page number corresponding to
EEPROM locations 280hex and 281hex) to
the IEEA[3:0] register.
Page Erase command.
Wait 7.1ms before sending any further
commands.
Load 0hex to the IEEA[3:0] register.
Load 8hex to the IEEA[7:4] register.
Load 2hex to the IEEA[9:8] (IRSP[3:0])
register.
Load 0hex to the DHR[3:0] register.
Load 4hex to the DHR[7:4] register.
Write EEPROM. 40hex is loaded to EEPROM
address 280hex, which is the low byte
location corresponding to a Temp-Index
pointer value of 40.
Load 1 to the IEEA[3:0] register. IEEA[7:4]
and IEEA[9:8] already contain 8 and 2,
respectively.
Load Chex to the DHR[3:0] register.
Load 8hex to the DHR[7:4] register.
Write EEPROM. 8Chex is loaded to
EEPROM address 281hex, which is the high
byte location corresponding to a Temp-
Index pointer value of 40.
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