pca9561 NXP Semiconductors, pca9561 Datasheet - Page 6

• Manufacturer Part Number: pca9561
• Description: Quad 6-bit Multiplexed I2c Eeprom Dip Switch
• Manufacturer: NXP Semiconductors

1. This table is valid when not overridden by I
Philips Semiconductors
EXTERNAL CONTROL SIGNALS
The Write Protect (WP) input is used to control the ability to write the content of the non-volatile registers. If the WP signal is logic 0, the I
will be able to write the contents of the non-volatile registers. If the WP signal is logic 1, data will not be allowed to be written into the
non-volatile registers. In this case, the slave address and the command code will be acknowledged but the following data bytes will not be
acknowledged and the EEPROM is not updated.
The factory default for the contents of the non-volatile register are all logic 0. These stored values can be read or written using the I
(described in the next section).
The WP, MUX_IN*, and MUX_SELECT signals have internal pull-up resistors. See the DC and AC Characteristics for hysteresis and signal
spike suppression figures.
Function Table
NOTE:
POWER-ON RESET (POR)
When power is applied to V
reset condition is released and the PCA9561 volatile registers and state machine will initialize to their default states.
The MUX_OUT pin values depend on the MUX_SELECT logic level:
2004 May 17
– if MUX_SELECT = 0, the MUX_OUT pin output values will equal the previously stored EEPROM byte 0 values regardless of the last
– if MUX_SELECT = 1, the MUX_OUT output values will equal the MUX_IN pin input values as shown in the Function Table.
Quad 6-bit multiplexed I
non-volative EEPROM byte selected by the command byte prior to power down.
WP
X
X
0
1
1
DD
, an internal power-on reset holds the PCA9561 in a reset state until V
MUX_SELECT
2
2
C EEPROM DIP switch
C control register.
X
X
0
1
6
Write to the non-volatile registers through I
Write to the non-volatile registers through I
(EEPROM selected through I
MUX_OUT from EEPROM byte 0–3
MUX_OUT from MUX_IN inputs
COMMANDS
DD
has reached V
2
C – see Table 2)
2
POR
C-bus not allowed
2
C-bus allowed
. At that point, the
PCA9561
Product data sheet
2
C-bus
2
C-bus