DS2406 Maxim, DS2406 Datasheet - Page 16

• Manufacturer Part Number: DS2406
• Description: The DS2406 Dual Addressable Switch Plus Memory offers a simple way to remotely control a pair of open drain transistors and to monitor the logic level at each transistor's output via the 1-Wire® bus for closed loop control
• Manufacturer: Maxim

After the Channel Control bytes have been transmitted the bus master receives the Channel Info byte
(Figure 9). This byte indicates the status of the channel flip-flops, the PIO pins, the activity latches as
well as the availability of channel B and external power supply. To be able to read from a PIO channel,
the output transistor needs to be non-conducting, which is equivalent to a 1 for the channel flip-flop.
Reading 0 for both the channel flip-flop and the sensed level indicates that the output transistor of the PIO
is pulling the node low. For the Channel Info byte PIO A and B are sampled at the same time, as in the
synchronous mode. If channel B is available, bit 6 of the Channel Info Byte reads 1. For 1-channel
versions of the DS2406, the PIO B sensed level, channel flip-flop value, and activity latch value should
be ignored. Without an external supply, the supply indication bit (bit 7) reads 0. As long as the voltage
applied to the V
CHANNEL INFO BYTE Figure 9
ONE-CHANNEL READ/WRITE Figure 10a
1-WIRE
1-WIRE
TWO-CHANNEL READ Figure 10b
1-WIRE
1-WIRE
WRITE (IC=0, Asynchronous Mode)
READ (IC=0, Asynchronous Mode)
PIO
Indication
PIO-A
PIO-B
PIO
Supply
supply
0 = no
BIT 7
PIO SAMPLING
1
IC=1, SYNCHRONOUS MODE
IC=0, ASYNCHRONOUS MODE
td1
A1
A1
0 = channel
Number of
15 µs < td1 < 60 µs
Channels
CC
A only
BIT 6
2
pin is high enough to operate the device this bit will read 1.
B2
B1
Activity
3
PIO-B
BIT 5
Latch
A3
A3
4
B4
B3
Activity
td0
PIO-A
BIT 4
Latch
200 ns < td0 < 300 ns
16 of 32
PIO SAMPLING
5
A5
A5
Sensed
BIT 3
PIO B
Level
6
B6
B5
Sensed
PIO A
BIT 2
Level
7
A7
A7
Flip-Flop Q
Channel
8
PIO-B
BIT 1
B7
B8
9
Flip-Flop Q
Channel
A9
A9
PIO-A
BIT 0