cs5378 Cirrus Logic, Inc., cs5378 Datasheet - Page 21

• Manufacturer Part Number: cs5378
• Description: Low-power Single-channel Decimation Filter
• Manufacturer: Cirrus Logic, Inc.

5. RESET CONTROL
The CS5378 reset signal is active low. When re-
leased, a series of self-tests are performed and the
device either actively boots from an external EE-
PROM or enters an idle state waiting for microcon-
troller configuration.
5.1 Pin Descriptions
RESET - Pin 18
Reset input, active low.
GPIO7:BOOT - Pin 28
Boot mode select, latched immediately following
reset. Weak (~100 kΩ) internal pull-up defaults
high, external 10 kΩ pull-down required to set low.
5.2 Reset Self-Tests
After RESET is released but before booting, a se-
ries of digital filter self-tests are run. Results are
DS639F1
Program ROM
Data ROM
Program RAM
Data RAM
Execution Unit
BOOT
Self-Test
1
0
Type
EEPROM boot
Microcontroller boot
0x00000A
0x0000A0
0x000A00
0x00A000
0x0A0000
Reset Mode
Code
Pass
RESET
Figure 11. Reset Control Block Diagram
0x00000F
0x0000F0
0x000F00
0x00F000
0x0F0000
Code
Fail
Self-Tests
SELFTEST
Register
combined into the SELFTEST register (0x2F),
with 0x0AAAAA indicating all passed. Self-tests
require 60 ms to complete.
5.3 Boot Configurations
The logic state of the BOOT pin after reset deter-
mines if the CS5378 actively reads configuration
information from EEPROM or enters an idle state
waiting for a microcontroller to write configuration
commands.
EEPROM Boot
When the BOOT pin is high after reset, the CS5378
actively reads data from an external serial EE-
PROM and then begins operation in the specified
configuration. Configuration commands and data
are encoded in the EEPROM as specified in the
‘Configuration By EEPROM’ section of this data
sheet, starting on page 25.
Microcontroller Boot
When the BOOT pin is low after reset, the CS5378
enters an idle state waiting for a microcontroller to
write configuration commands and initialize filter
operation. Configuration commands and data are
written as specified in the ‘Configuration By Mi-
crocontroller’ section of this data sheet, starting on
page 30.
EEPROM
BOOT
Boot
Pin
1
0
µController
Boot
CS5378
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