ZL9101M Datasheet, PDF (11/17 Pages) Intersil Corporation – Digital DC/DC PMBus 12A Module

ZL9101M
duty cycle to match the original target voltage and the output will
ramp down to the preconfigured output voltage.
If a pre-bias voltage higher than the overvoltage limit exists, the
device will not initiate a turn-on sequence and will declare an
overvoltage fault condition to exist. In this case, the device will
respond based on the output overvoltage fault response method
that has been selected. See “Output Overvoltage Protection” on
page 10 for response options due to an overvoltage condition.
Note that pre-bias protection is not offered for current sharing
groups that also have tracking enabled.
Output Overcurrent Protection
The ZL9101M can protect the power supply from damage if the
output is shorted to ground or if an overload condition is imposed
on the output. The following overcurrent protection response
options are available:
1. Initiate a shutdown and attempt to restart an infinite number
of times with a preset delay period between attempts.
2. Initiate a shutdown and attempt to restart a preset number of
times with a preset delay period between attempts.
3. Continue operating for a given delay period, followed by
shutdown if the fault still exists.
4. Continue operating through the fault (this could result in
permanent damage to the power supply).
5. Initiate an immediate shutdown.
The default response from an overcurrent fault is an immediate
shutdown of the controller. The controller will continuously check
for the presence of the fault condition, and if the fault condition
no longer exists the device will be re-enabled.
Please refer to Application Note AN2033 for details on how to
select specific overcurrent fault response options via I²C/SMBus.
Thermal Overload Protection
The ZL9101M includes a thermal sensor that continuously
measures the internal temperature of the module and shuts
down the controller when the temperature exceeds the preset
limit. The default temperature limit is set to +125°C in the
factory, but the user may set the limit to a different value if
desired. See Application Note AN2033 for details. Note that
setting a higher thermal limit via the I²C/SMBus interface may
result in permanent damage to the controller. Once the module
has been disabled due to an internal temperature fault, the user
may select one of several fault response options as follows:
1. Initiate a shutdown and attempt to restart an infinite number
of times with a preset delay period between attempts.
2. Initiate a shutdown and attempt to restart a preset number of
times with a preset delay period between attempts.
3. Continue operating for a given delay period, followed by
shutdown if the fault still exists.
4. Continue operating through the fault (this could result in
permanent damage to the power supply).
5. Initiate an immediate shutdown.
If the user has configured the module to restart, the controller
will wait the preset delay period (if configured to do so) and will
then check the module temperature. If the temperature has
dropped below a threshold that is approximately +15 °C lower
than the selected temperature fault limit, the controller will
attempt to re-start. If the temperature still exceeds the fault limit
the controller will wait the preset delay period and retry again.
The default response from a temperature fault is an immediate
shutdown of the module. The controller will continuously check
for the fault condition, and once the fault has cleared the
ZL9101M will be re-enabled.
Please refer to Application Note AN2033 for details on how to
select specific temperature fault response options via
I²C/SMBus.
I²C/SMBus Communications
The ZL9101M provides an I²C/SMBus digital interface that
enables the user to configure all aspects of the module operation
as well as monitor the input and output parameters. The
ZL9101M can be used with any I²C host device. In addition, the
module is compatible with SMBus version 2.0. Pull-up resistors
are required on the I²C/SMBus as specified in the SMBus 2.0
specification. The ZL9101M accepts most standard PMBus
commands. When controlling the device with PMBus commands,
it is recommended that the enable pin is tied to SGND.
I²C/SMBus Module Address Selection
Each module must have its own unique serial address to
distinguish between other devices on the bus. The module
address is set by connecting a resistor between the SA pin and
SGND. Table 2 lists the available module addresses.
TABLE 2. SMBus ADDRESS RESISTOR SELECTION
R_SA0
10
11
12.1
13.3
14.7
16.2
17.8
19.6
21.5
23.7
26.1
28.7
31.6
34.8
38.3
42.2
46.4
51.1
56.2
SMBus Address
0x19
0x1A
0x1B
0x1C
0x1D
0x1E
0x1F
0x20
0x21
0x22
0x23
0x24
0x25
0x26
0x27
0x28
0x29
0x2A
0x2B
11
FN7669.0
December 20, 2010