DS4305K Maxim Integrated, DS4305K Datasheet - Page 7

• Manufacturer Part Number: DS4305K
• Description: Power Management IC Development Tools
• Manufacturer: Maxim Integrated
• Series: DS4305, DS4305Kr

Specifications of DS4305K

• Part # Aliases: 90-4305K-000

During the V
nally adjusts the on-board DAC until V
V
accuracy, V
in EEPROM. The storage period lasts for the duration of
the EEPROM write time, t
procedure has completed, V
and if necessary V
adjustment procedure can be repeated to fine-tune
V
Following each self-adjust procedure, V
indefinitely, even if the DS4305 is power cycled.
Figure 2 details an example of how the DS4305 can be
adjusted in an application. During factory alignment, a
three/four-node bed-of-nails is used to: (1) provide the
adjustment voltage through the V
ADJ input, and (3) sense the needed feedback para-
meter. During manufacture, an automated test proce-
dure adjusts V
parameter is optimized. After the bed-of-nails operation
is complete, both the V
Figure 2. Application Circuit
IN
OUT
. After V
within the V
Automated Programming Procedure
STEP 1:
SET REFERENCE
VOLTAGE
STEP 2:
TOGGLE ADJ
STEP 3:
DETERMINE IF
THE REFERENCE
VOLTAGE NEEDS
ADJUSTMENT
OUTTA
OUT
OUT
OUT,
AUTOMATED TEST EQUIPMENT
OUTQ
has stabilized to within the tracking
self-adjust period, the DS4305 inter-
, of V
IN
by changing V
can be readjusted and the entire
IN
range.
IN
VOLTAGE SOURCE
, it will be automatically stored
CONTROLLED
and ADJ inputs are left open
DIGITAL PIN DRIVER
W
DIGITALLY
. After the first adjustment
MEASUREMENT
CONTROLLED
DIGITALLY
OUT
IN
IN
can be measured,
, until the feedback
pin, (2) control the
_____________________________________________________________________
OUT
OUT
Electronically Programmable
matches
is saved
BED-OF-NAILS
ACCESS
TEST
circuit. V
the same procedure. The closed-loop nature of the
adjustment process removes all the system inaccura-
cies such as resistor tolerances, amplifier offsets, gain
mismatches, and even the inaccuracies in the automat-
ed equipment that provides the reference voltage.
The Typical Operating Circuit shows an example of
how the DS4305 can replace most existing calibration
solutions. Many power supplies use a shunt voltage ref-
erence to provide the internal reference voltage, and
fine-tune adjustments are often made with hand-select-
ed discrete resistors. The DS4305 replaces this cum-
bersome arrangement with a solution that is capable of
being adjusted by automated techniques. An additional
benefit of the DS4305 is the ability to provide a much
lower voltage (down to 300mV) than is possible with
shunt voltage references. Another benefit of the
DS4305 is the ability to be adjusted after the unit has
been fully assembled and tested, resulting in a much
more flexible manufacturing arrangement, lower inven-
tory costs, and a quicker time-to-market.
GND
ADJ
V
OUT
IN
DEVICE-UNDER-TEST (DUT)
PARAMETER MEASURED
Voltage Reference
DURING CALIBRATION
can be readjusted at any time by following
SAMPLE-AND-
EEPROM
VOLTAGE
INFINITE-
DS4305
HOLD
Typical Operating Circuit
V
V
4.0V TO 5.5V
CC
OUT
ADJUSTMENT
REQUIRING
CIRCUITRY
VOLTAGE
7