LTM8026 LINER [Linear Technology], LTM8026 Datasheet - Page 11

• Manufacturer Part Number: LTM8026
• Description: 36VIN, 5A, 2-Quadrant CVCC Step-Down
• Manufacturer: LINER [Linear Technology]

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operaTion
The LTM8052 is a standalone nonisolated constant-voltage,
constant-current step-down switching DC/DC power sup-
ply that can deliver up to 5A of positive or 6A of negative
output current. This µModule regulator provides a precisely
regulated output voltage programmable via one external
resistor from 1.2V to 24V. The input voltage range is 6V
to 36V. Given that the LTM8052 is a step-down converter,
make sure that the input voltage is high enough to support
the desired output voltage and load current.
The LTM8052 is a 2-quadrant device, meaning that it
can both source and sink current in order to regulate its
output voltage. Most traditional voltage regulators are one
quadrant; that is, they only source current. If the load, for
whatever reason, forces current into a traditional regulator,
the output voltage will typically rise. In a similar situation,
V
RUN
SS
SYNC
V
CTL_I
CTL_T
COMP
IN
REF
10k
2.2nF
0.2µF
CONTROLLER
CURRENT
MODE
GND
RT
V
IN
REGULATOR
INTERNAL
the LTM8052 will sink current to keep the output voltage
in regulation.
It should be clear that the above situation is only possible
if the load is providing energy to the LTM8052 output.
The LTM8052 will be able to maintain the output voltage
at the target regulation point as long as the current from
the load does not exceed its negative current limit. If
the current does exceed the negative current limit, the
LTM8052 output will start to rise. If the output continues
to rise, the LTM8052’s output overvoltage protection
circuitry will turn off the internal power switches, and
the output will be free to rise. If this voltage rises above
the LTM8052 input voltage, current will flow through an
internal diode, and the output will be clamped to a diode
drop above the input.
2.2µH
R
SENSE
ADJ
10k
LTM8052
V
2.2µF
OUT
8026 BD
11
8052fa