Datasheet

Preliminary Technical Data EVAL-ADM106x
PROGRAMMABLE DIRECT OUTPUTS (PDO)
The ADM106x features ten PDOs (eight inputs in the case of
ADM1068/9). These outputs can be used to control the turn-on/off
of supplies. The outputs are highly configurable. They can be
programmed to pull- up to a number of different options. The
outputs can be programmed as follows:–
• Open Drain (allowing the user to connect an external pull-up
resistor)
• Open Drain with weak pull-up to VDD
• Push Pull to VDD
• Open-drain with weak pull-up to VPn
• Push-pull to VPn
• Strong pull-down to GND
• Internally charge- pumped high drive (12V- Available on PDO 1-
6 Only)
The data driving each of the PDO’s can come from one of three
sources. These are:
• An output from the Sequencing Engine (normal operation- where
the ADM106x independently controls the sequence of supplies).
• Directly from the SMBus. A PDO can be configured so that the
SMBus has direct control over it. This enables software control of
the PDO’s. Thus, a microcontroller could be used to initiate a
software power-up/power-down sequence.
• An On- Chip Clock. A 100KHz clock is generated on the device.
This clock can be made available on any of the PDO’s. It could be
used to clock an external device such as a LED, for example.
Figure 44. Programming outputs on ADM106x
SEQUENCING ENGINE
The logical core of the ADM106x is the Sequencing Engine.
This is a state machine based architecture which determines
how the ADM106x reacts to events as they occur. These
“events” could be a supply coming in to tolerance, a supply
failing, a digital input being asserted etc. The ADM106x
provides 63 states, allowing the device to control the sequence
of up to 63 events. The ADM106x’s control of the outside
world is through its programmable outputs, so their logical
status can be set in each state. For instance, the first state
could be set up to check that a supply is in tolerance. Once this
is the case, the sequencing engine can proceed to the next state
where the next supply is enabled by driving its controlling PDO
high. A diagram of a state cell is shown below.
STATE
Timeout
onitor
Fault
End-of-Step
M
Figure 45. ADM106x State Cell
The diagram shows that once a state is entered, there are three
possible ways to leave that state:-
1. End of Step- This is the primary way to leave a state.
The user can choose a single event (e.g.) an input
signal going high- to allow the engine to progress to
the next state. By selecting the end of step condition
in a number of states, the user defines the sequence in
which event must happen (i.e.) the sequence in which
supplies are turned on/off.
2. Timeout- This provides a safety net if an End-of Step
Normal o
p
eration
FET Drive
r
Pull-up to VP1,VP2,
VP3,VP4 or VDDCAP
Rev. PrB | Page 25 of 38