MAX14900E Datasheet, PDF (17/31 Pages) Maxim Integrated Products – Global and Per-Channel Diagnostics

MAX14900E
Octal, High-Speed, Industrial, High-Side Switch
Serial Controller Interface
The MAX14900E can be configured, controlled and/or
monitored on a per-channel basis via its SPI interface (see
Table 1). Daisy-chaining multiple MAX14900E devices
is supported to reduce the required number of CS and/
or isolator pins. Figure 5 shows an example of daisy-
chaining two MAX14900E devices. Daisy-chaining operates
both with 8-bit and 16-bit serial data: S16/IN8 = X.
The MAX14900E uses SPI mode 0 with CPOL = 0 and
CPHA = 0. When the CS input transitions low, diagnostics
and status information is sampled and stored in the inter-
nal SPI shift register and the SDO output becomes active.
This data is clocked out of SDO on each falling CLK edge
while new SDI data is sampled and stored in the shift
register on each rising CLK edge. When CS transitions
high at the end of the SPI cycle, the current data in the
SPI shift register is latched into the MAX14900E and the
new configuration and/or setting data changes the driver
states. Figure 6 illustrates the sampling of internal signals
dependent on CS transitions.
SCLK
µC
MOSI
CS
MISO
CLK
MAX14900E
DATAB I TS
SDI _{S H I F T R E G} SDO
CS ^{D I A G N S T C}
CLK
MAX14900E
DATAB I TS
SDI _{S H I F T R E G}
SDO
CS ^{D I A G N S T C}
Figure 5. Daisy-Chained MAX14900E Devices with 8-Bit Serial Mode
CS
DIAGNOSTICS
/STATUS
OUTPUT
LATCHED
Figure 6. Internal Sampling Events Timing Diagram
PREVIOUS STATE
NEW STATE
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