ADM1041-EVAL Analog Devices Inc, ADM1041-EVAL Datasheet - Page 17

• Manufacturer Part Number: ADM1041-EVAL
• Description: BOARD EVALUATION ADM1041
• Manufacturer: Analog Devices Inc

Specifications of ADM1041-EVAL

• Main Purpose: AC/DC, Secondary Side
• Outputs And Type: 1, Non-Isolated
• Power - Output: 24W
• Voltage - Output: 12V
• Current - Output: 2A
• Voltage - Input: 85 ~ 132VAC
• Board Type: Fully Populated
• Utilized Ic / Part: ADM1041
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Frequency - Switching: -
• Regulator Topology: -
• Lead Free Status / Rohs Status: Not Compliant

TERMINOLOGY
Table 5.
Mnemonic
POR
UVL
CVMode
CCMode
UVP
OVP
OCP
OTP
UVB
DC_OK
AC_OK
DC_OKondelay
DC_OKoffdelay
Debounce Digital Noise Filter
AC
SENSE
1
Description
The DC_OK output is kept false for typically 100 ms to 900 ms during power-up.
Power-On Reset. When V
the logic into a state that allows a clean start-up.
Undervoltage Lockout. This is used on V
V
Constant Voltage Mode. This is the normal mode of operation of the power supply main output. The
output voltage remains constant over the whole range of current specified.
Constant Current Mode. This mode of operation occurs when the output is overloaded until or unless
a shutdown event is triggered. The output current control level remains constant down to 0 V.
Undervoltage Protection. If the output being monitored is detected as going under voltage, the UVP
function sends a fault signal. After a delay, PEN goes false, the output is disabled, and either latch-off
or an auto-restart occurs, depending on the mode selected. The DC_OK output also goes false
immediately to show that the output is out of tolerance.
Overvoltage Protection. If the output being monitored is detected as going over voltage, the OVP
function latches and sends a fault signal, PEN goes false, and CBD goes true. The DC_OK output also
goes false immediately. OVP faults are always latching and require the cycling of PSON or V
SMBus command to reset the latch.
Overcurrent Protection. If the output being monitored is detected as going over current for a certain
time, the OCP function sends out a fault signal that triggers a shutdown that can be latched or
allowed to auto-restart, depending on the mode selected. Prior to shutting down, the DC_OK output
goes false warning the system that output will be lost. The latch is the same one used for OVP. For
auto-restart, the OCP time out period is configurable.
Overtemperature Protection. If the temperature being sensed is detected as going over the selected
limit, the OTP function sends out a fault signal that triggers a shutdown that can be latched or allowed
to auto-restart depending on the mode selected. Prior to shutting down, the DC_OK output goes false
warning the system that output will be lost. The latch is the same one used for OVP.
Undervoltage Blanking. The UVP function is blanked (disabled) during power-up or if the AC
function is false (ac line voltage is low). When in constant current mode, UVB is disabled. The status of
AC
SMBus with the help of an external microprocessor or by using AC_OKLink. When in constant current
mode, due to an overload, UVB is applied for the overcurrent ride through period.
The DC_OK function advises the system on the status of the power supply. When it is false, the system
is assured of at least 1 ms of operation if ac power is lost for any reason. Other turn-off modes provide
more warning time. This pin is an open-drain output. It can be configured as a P-channel pull-up or an
N-channel pull-down. It may also be configured as positive or negative (inverted) logic.
The AC_OK function advises the system whether or not sufficient bulk voltage is present to allow
reliable operation. The system may choose to shut down if this pin is false. The power supply normally
tries to maintain normal operation as long as possible, although DC_OK goes false when only a
millisecond or so of operation time is left. This pin is an open-drain output. It can be configured as a
P-channel pull-up or an N-channel pull-down. It may also be configured as positive or negative
(inverted) logic.
When the system is to be shut down in response to PSON going low, or in response to an OCP or OTP
event, a signal is first sent to the DC_OK output to go false as a warning that power is about to be lost.
PEN is signaled false typically 2 ms later (configurable).
All of the inputs to the logic core are first debounced or digitally filtered to improve noise immunity.
The debounce period for OV events is in the order of 16 µs, for UV events it is 450 µs, and for PSON it is
typically 80 ms (configurable).
A voltage from the secondary of the power transformer, which can provide an analog of the bulk
supply, is rectified and lightly filtered and measured by the ac sense function. At start-up, if this
voltage is adequate, this function signals the end user system that it is okay to start. If a brown-out
occurs or ac power is removed, this function can provide early warning that power is about to be lost
and allow the system to shut down in an orderly manner. While AC
means undervoltage protection is not initiated. If ac power is so low that the converter cannot
continue to operate, other protection circuits on the primary side normally shut down the converter.
When an adequate voltage level is resumed, a power-up cycle is initiated.
DD
SENSE
is below a specific voltage.
must be known to the IC, either by virtue of the on-board AC
Rev. A | Page 17 of 64
DD
is initially applied to the ASIC, the POR function clears all latches and puts
DD
to prevent spurious modes of operation that might occur if
SENSE
SENSE
is low, UVB is enabled, which
or communicated by the
ADM1041
DD
SENSE
or