|
|
PDF MP4568 Data sheet ( Hoja de datos )
| Número de pieza | MP4568 | |
| Descripción | Step-Down Converter | |
| Fabricantes | MPS | |
| Logotipo |  |
|
Hay una vista previa y un enlace de descarga de MP4568 (archivo pdf) en la parte inferior de esta página. Total 16 Páginas | ||
|
No Preview Available !
MP4568
60V, 100mA Synchronous
Step-Down Converter
DESCRIPTION
The MP4568 is a high-frequency, step-down,
switching regulator with integrated high-
side/low-side, high-voltage power MOSFETs. It
provides a highly efficient output of up to
100mA.
60V rated MOSFETs and 4.5V to 45V operation
range accommodates a variety of step-down
applications in automotive input environment. A
5μA shutdown mode quiescent current allows
use in battery-powered applications.
It allows for high power conversion efficiency
over a wide load range by scaling down the
switching frequency under light-load condition
to reduce the switching and gate driver losses.
The switching frequency during start-up and
short circuit also can be scaled down to helps
prevent inductor current runaway. Thermal
shutdown provides reliable, fault-tolerant
operation.
The MP4568 is available in a 3mmx3mm
QFN10 package.
TYPICAL APPLICATION
VIN
R3
2M
EN
R4
100k
U1
10 IN
C2
0.1uF
SW
2
C1
10uF
MP4568
9 EN
8 ENHY
6 ILIM
7 SS
BIAS 4
FB 5
L1
100uH
C3
22uF
5V/100mA
VOUT
R1
1.2M
R2
300k
FEATURES
20μA Quiescent Current
Wide 4.5V to 45V Operating Range with 50V
Input OVP
60V Integrated MOSFETs with 0.7Ω and
2.25Ω Ron
Programmable Switching Frequency
Stable with Ceramic Output Capacitors
Low Output Ripple
Programmable Soft-Start
Adjustable Input UVLO Hysteresis
Precision Peak Current Limit without
Current-Sensing Resistor
Programmable Peak Current Limit
>90% Efficiency at 10V VIN to 5V VOUT/2mA
1.0V Feedback Reference Voltage
Low Shutdown Mode Current: <5μA
3mmx3mm QFN10 Package
APPLICATIONS
4mA to 20mA Current Loops
Automotive Systems
Industrial Power Systems
Distributed Power Systems
Battery Powered Systems
All MPS parts are lead-free and adhere to the RoHS directive. For MPS green
status, please visit MPS website under Products, Quality Assurance page.
“MPS” and “The Future of Analog IC Technology” are registered trademarks of
Monolithic Power Systems, Inc.
MP4568 Rev. 1.01
8/18/2013
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2013 MPS. All Rights Reserved.
1
http://www.Datasheet4U.com
1 page  
MP4568―60V, 100mA, SYNCHRONOUS STEP-DOWN CONVERTER
TYPICAL CHARACTERISTICS (continued)
VIN=12V, TJ=25oC, unless otherwise noted.
MP4568 Rev. 1.01
8/18/2013
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2013 MPS. All Rights Reserved.
5
5 Page 
MP4568―60V, 100mA, SYNCHRONOUS STEP-DOWN CONVERTER
Under-Voltage Lockout
VIN under voltage lockout (UVLO) protects the
chip from operating below the operational supply
voltage range. The UVLO-rising threshold is
about 4V while its trailing threshold is about 3.5V.
Soft-Start
Reference-type soft-start prevents the converter
output voltage from overshooting during startup.
When the chip starts, the internal circuitry
generates a constant current to charge external
SS capacitor. The soft-start (SS) voltage slowly
ramps up from 0V at a slow pace set by the soft-
start time. When VSS is less than the VREF, VSS
overrides VREF so the error amplifier uses VSS
instead of VREF as the reference. When VSS is
higher than VREF, VREF resumes control.
VSS is also associated with VFB. Though VSS can
be much smaller than VFB, it can only barely
exceed VFB. If somehow VFB drops, VSS tracks
VFB. This function aides in short-circuit recovery:
when a short-circuit is removed, the SS ramps up
as if it is a fresh soft-start process. This prevents
output voltage overshoot.
Thermal Shutdown
Thermal shutdown prevents the chip from
thermally running away. When the silicon die
temperature exceeds its upper threshold, the
thermal shutdown feature shuts down the whole
chip. When the temperature falls below its lower
threshold, the chip resumes function.
Floating Driver and Bootstrap Charging
The external bootstrap capacitor powers the
floating MOSFET driver. This floating driver has
its own UVLO protection, with a rising threshold
of about 2.4V with a hysteresis of about 300mV.
During this UVLO, the SS voltage of the
controller resets to zero. When the UVLO is
disabled, the controller follows the soft-start
process.
The dedicated internal bootstrap regulator
charges and regulates the bootstrap capacitor to
about 5V. When the voltage difference between
BST and SW falls below its working parameters,
a PMOS pass transistor connected from VIN to
BST turns on to charge the bootstrap capacitor.
The current path is from VIN to BST and then to
SW. The external circuit must have enough
voltage headroom to accommodate charging.
As long as VIN is sufficiently higher than SW, the
bootstrap capacitor can charge. When the power
MOSFET is ON, VIN is about equal to SW so the
bootstrap capacitor cannot charge. The best
charging period occurs when the external free-
wheeling diode is on so that VIN - VSW is at its
largest. When there is no current in the inductor,
VSW equals VOUT so the difference between VIN
and VOUT can charge the bootstrap capacitor.
Under higher duty cycle operating conditions, the
time period may not fully-charge the capacitor.
If the external circuit does not have sufficient
voltage and time to charge the bootstrap
capacitor, extra external circuitry can be used to
ensure the bootstrap voltage in normal operation
region.
Startup and Shutdown
If both VIN and VEN are higher than their
appropriate thresholds, the chip starts operating.
The reference block starts first, generating stable
reference voltage and currents, and then enables
the internal regulator. The regulator provides
stable supply for the rest device.
While the internal supply rail is high, an internal
timer holds the power MOSFET off for about
50µsec to blank startup glitches. When the
internal soft-start block is enabled, it first holds its
SS output low and then slowly ramps up.
Three events shut down the chip: VEN low, VIN
low, and junction temperature triggers the
thermal shutdown threshold. For shutdown, the
signaling path is blocked first to avoid any fault
triggering. Internal supply rail are pulled down
then. The floating driver is not subject to this
shutdown command, but its charging path is
disabled.
MP4568 Rev. 1.01
8/18/2013
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2013 MPS. All Rights Reserved.
11
11 Page | ||
| Páginas | Total 16 Páginas | |
| PDF Descargar | [ Datasheet MP4568.PDF ] | |
Hoja de datos destacado
| Número de pieza | Descripción | Fabricantes |
| MP4561 | Step-Down Converter | MPS |
| MP4566 | Step-Down Converter | MPS |
| MP4568 | Step-Down Converter | MPS |
| Número de pieza | Descripción | Fabricantes |
| SLA6805M | High Voltage 3 phase Motor Driver IC. |
 Sanken |
| SDC1742 | 12- and 14-Bit Hybrid Synchro / Resolver-to-Digital Converters. |
 Analog Devices |
|
DataSheet.es es una pagina web que funciona como un repositorio de manuales o hoja de datos de muchos de los productos más populares, |
| DataSheet.es | 2020 | Privacy Policy | Contacto | Buscar |