MP024-10

– PRIMARY-SIDE CC/CV REGULATOR

MP024-10 Rev.1.0

www.MonolithicPower.com

17

4/17/2017

MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.

© 2017 MPS. All Rights Reserved.

If CP is connected with a resistor, then there

combination (see Figure 8).

CP

Figure 8: External Configuration of CP

The entire customization process is completed

before start-up and latched in a register, so it

does not have any influence on the normal

operation.

0

Ω/NC

0.4

10k

Ω/NC

0.3

20k

Ω/NC

0.35

40k

Ω/NC

0.5

NC/1

μF

0.4

To

enable

the

overload

protection

(OLP)

function in CC mode, the sampling on the FB

voltage should be running, and the sampling

Leading-Edge Blanking

The MP024-10 uses a leading-edge blanking

period when the MOSFET turns on. Leading-

edge blanking is used to prevent a false

termination of the switching pulse caused by

the turn-on current spike. During this blanking

period,

the

current

sense

comparator

is

disabled, and the MOSFET cannot be turned

off.

Discontinuous

Conduction

Mode

(DCM)

Detection

The MP024-10 is designed to operate in

discontinuous conduction mode (DCM) in both

CV and CC modes. To avoid operating in

continuous

conduction

mode

(CCM),

the

MP024-10 implements a zero-current detection

IC does not begin the next cycle until ZCD is

detected.

During normal operation, the blanking time for

ZCD is synchronized with the FB sampling time

(i.e.: ZCD always starts after the sampling

phase is done). There is also a soft-start (SS)

function on the ZCD blanking time that prevents

ZCD from being falsely triggered when the

output capacitor is not charged up. During the

start-up period, the blanking time for ZCD

sampling time in three cycles.

Protection Features (OVP, OCkP, SSP, and

OLP)

The MP024-10 includes over-voltage protection

(OVP), open-circuit protection (OCkP), sensing-

short protection (SSP), and overload protection

each cycle, OCkP is triggered. If the maximum

turn on time is reached, SSP is triggered. If the

consecutive cycles, OLP is triggered. The

MP024-10 immediately shuts down the driving

signals and enters hiccup mode when any of

these protection features are triggered and

resumes normal operation when the fault has

been removed.

OLP is not enabled until the soft-start period of

the ZCD blanking time is finished.

Over-Temperature Protection (OTP)

When the junction temperature of the IC

exceeds the thermal shutdown threshold, over-

temperature protection (OTP) is triggered, and

the IC stops switching. The MP024-10 resumes

normal operation when the junction temperature

drop exceeds the thermal shutdown hysteresis.

Output Cable Compensation

The MP024-10 has an internal output cable

compensation circuit (see Figure 9). A switching

synchronized with the switching frequency. The

amplitude of this signal is proportional to the

current limit threshold. The switching signal is

output to CP through a 1M

Ω resistor. A low-

pass filter can be implemented by placing an

external capacitor on CP, and a DC voltage

can be derived on CP.

An

internal

current

sinking

into

FB

is

upper resistor of the divider implements the

output cable compensation function.