MPS MP2106DK, MP2106DQ Schematics

TM

MP2106

The Future of Analog IC Technology

DESCRIPTION

The MP2106 is a 1.5A, 800KHz synchronous
buck converter designed for low voltage
applications requiring high efficiency. It is
capable of providing output voltages as low as

0.9V, and integrates top and bottom switches to
minimize power loss and component count. The
800KHz switching frequency reduces the size
of filtering components, further reducing the
solution size.

The MP2106 includes cycle-by-cycle current
limiting and under voltage lockout. The internal
power switches, combined with the tiny 10-pin
MSOP and QFN packages, provide a solution
requiring a minimum of surface area.

EVALUATION BOARD REFERENCE

Board Number Dimensions

EV2106DQ/DK-00A 2.5”X x 2.0”Y x 0.5”Z

TM

1.5A, 15V, 800KHz

Synchronous Buck Converter

FEATURES

• 1.5A Output Current

• Synchronous Rectification

• Internal 210m and 255m Power Switches

• Input Range of 2.6V to 15V

• >90% Efficiency

• Zero Current Shutdown Mode

• Under Voltage Lockout Protection

• Soft-Start Operation

• Thermal Shutdown

• Internal Current Limit (Source & Sink)

• Tiny 10-Pin MSOP or QFN Package

APPLICATIONS

• DC/DC Regulation from Wall Adapters

• Portable Entertainment Systems

• Set Top Boxes

• Digital Video Cameras, DECT

• Networking Equipment

• Wireless Modems

TYPICAL APPLICATION

INPUT

2.6V to 15V

R4

OFF ON

C5 C3

10nF

C1

3.3nF

R3

VIN BST

5

RUN

1

SS
COMP

MP2106

C6
10nF

3

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Power Systems, Inc.

Efficiency vs.

C7

10nF

67

LX

FB

PGNDSGNDVREF

9104

L1

8

2

R2

R1

OUTPUT

1.8V / 1.5A

C2

MP2106_TAC_S01

Load Current

100

VIN=3.3V

90

80

70

60

50

40

30

EFFICIENCY (%)

20

10

0

0.01 0.1 1 10

VIN=5V

LOAD CURRENT (A)

MP2106_TAC_EC02

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TM

MP2106 – 1.5A, 15V, 800KHz SYNCHRONOUS BUCK CONVERTER

PACKAGE REFERENCE

TOP VIEW

SGND

1

SS

2

FB

COMP

VREF

RUN

3

4

5

Part Number* Package Temperature

MP2106DK MSOP10

For Tape & Reel, add suffix –Z (eg. MP2106DK–Z)

*

For Lead Free, add suffix –LF (eg. MP2106DK–LF–Z)

ABSOLUTE MAXIMUM RATINGS

Input Supply Voltage VIN.............................. 16V

LX Voltage V

BST to LX Voltage .........................

Voltage on All Other Pins...............

Storage Temperature...............

Recommended Operating Conditions

Input Supply Voltage VIN..................2.6V to 15V

Output Voltage V

Operating Temperature..............

..................... –0.3V to VIN + 0.3V

LX

........................0.9V to 5.5V

OUT

10

PGND

9

LX

8

VIN

7

BST

6

MP2106_PD01-MSOP10

–40°C to +85°C

(1)

–0.3V to +6V
–0.3V to +6V

–55°C to +150°C

(2)

–40°C to +85°C

TOP VIEW

SS

1

FB

2

COMP

VREF

3

4

RUN

5

EXPOSED PAD

ON BACKSIDE

Part Number** Package Temperature

MP2106DQ

For Tape & Reel, add suffix –Z (eg. MP2106DQ–Z)

**

For Lead Free, add suffix –LF (eg. MP2106DQ–LF–Z)

Thermal Resistance

QFN10

(3mm x 3mm)

(3)

MSOP10 ................................150 ..... 65... °C/W

QFN10 ....................................50 ...... 12... °C/W

Notes:

1) Exceeding these ratings may damage the device.

2) The device is not guaranteed to function outside of its
operating conditions.

3) Measured on approximately 1” square of 1 oz copper.

SGND

10

PGND

9

LX

8

VIN

7

BST

6

MP2106_PD02-QFN10

–40°C to +85°C

θ

JA

θJC

ELECTRICAL CHARACTERISTICS

VIN = 5.0V, TA = +25°C, unless otherwise noted.

Parameter Symbol Condition Min Typ Max Units

Input Voltage Range VIN 2.6 15 V
Input Under Voltage Lockout 2.2 V
Input Under Voltage Lockout

Hysteresis
Shutdown Supply Current V
Operating Supply Current V
VREF Voltage V
RUN Input Low Voltage VIL 0.4 V
RUN Input High Voltage VHL 1.5 V
RUN Hysteresis 100 mV
RUN Input Bias Current 1 µA

Oscillator

Switching Frequency fSW 700 800 900 KHz
Maximum Duty Cycle D
Minimum On Time tON 200 ns

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100 mV

 0.3V 0.5 1.0 µA

RUN

> 2V, VFB = 1.1V 1.2 1.8 mA

RUN

VIN = 2.6V to 15V 2.4 V

REF

VFB = 0.7V 85 %

MAX

TM

MP2106 – 1.5A, 15V, 800KHz SYNCHRONOUS BUCK CONVERTER

ELECTRICAL CHARACTERISTICS (continued)

VIN = 5.0V, TA = +25°C, unless otherwise noted.

Parameter Symbol Condition Min Typ Max Units
Error Amplifier

Voltage Gain A
Transconductance GEA 300 µA/V
COMP Maximum Output Current ±30 µA
FB Regulation Voltage VFB 875 895 915 mV
FB Input Bias Current IFB VFB = 0.895V –100 nA

Soft-Start

Soft-Start Current ISS 2 µA

Output Switch On-Resistance

Switch On Resistance

Synchronous Rectifier On Resistance

Switch Current Limit (Source) 2.5 A
Synchronous Rectifier Current Limit

(Sink)
Thermal Shutdown 160

VEA

400 V/V

VIN = 5V 255 m
V

= 3V 315 m

IN

VIN = 5V 210 m
V

= 3V 255 m

IN

350 mA

°C

PIN FUNCTIONS

Pin # Name Description

Soft-Start Input. Place a capacitor from SS to SGND to set the soft-start period. The MP2106

1 SS

2 FB

3 COMP

4 VREF

5 RUN

6 BST

7 VIN

8 LX

9 PGND

10 SGND Signal Ground.

sources 2µA from SS to the soft-start capacitor at startup. As the SS voltage rises, the
feedback threshold voltage increases to limit inrush current during startup.

Feedback Input. FB is the inverting input of the internal error amplifier. Connect a resistive
voltage divider from the output voltage to FB to set the output voltage value.

Compensation Node. COMP is the output of the error amplifier. Connect a series RC network
to compensate the regulation control loop.

Internal 2.4V Regulator Bypass. Connect a 10nF capacitor between VREF and SGND to
bypass the internal regulator. Do not apply any load to VREF.

On/Off Control Input. Drive RUN high to turn on the MP2106; low to turn it off. For automatic
startup, connect RUN to VIN via a pullup resistor.

Power Switch Boost. BST powers the gate of the high-side N-Channel power MOSFET switch.
Connect a 10nF or greater capacitor between BST and LX.

Internal Power Input. VIN supplies the power to the MP2106 through the internal LDO
regulator. Bypass VIN to PGND with a 10µF or greater capacitor. Connect VIN to the input
source voltage.

Output Switching Node. LX is the source of the high-side N-Channel switch and the drain of the
low-side N-Channel switch. Connect the output LC filter between LX and the output.

Power Ground. PGND is the source of the N-Channel MOSFET synchronous rectifier. Connect
PGND to SGND as close to the MP2106 as possible.

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TM

MP2106 – 1.5A, 15V, 800KHz SYNCHRONOUS BUCK CONVERTER

TYPICAL PERFORMANCE CHARACTERISTICS

Circuit of Figure 2, VIN = 5V, V
otherwise noted.

= 1.8V, L1 = 5µH, C1 = 10µF, C2 = 22µF, TA = +25°C, unless

OUT

V

SW

5V/div.

V

AC Coupled

10mV/div.

V

AC Coupled

200mV/div.

1A/div.

Steady State Operation

1.5A Load

O

IN

I

L

Startup from Shutdown

1.5A Resistive Load

V

EN

2V/div.

V

OUT

1V/div.

MP2106-TPC01

V

SW

5V/div.

V

AC Coupled

10mV/div.

V

AC Coupled

20mV/div.

1A/div.

Steady State Operation

No Load

O

IN

I

L

Load Transient

V

OUT

AC Coupled

200mV/div.

I

L

1A/div.

I

LOAD

1A/div.

MP2106-TPC02

Startup from Shutdown

No Load

V

EN

2V/div.

V

OUT

1V/div.

MP2106-TPC03

I

L

1A/div.

V

SW

5V/div.

1ms/div.

Short Circuit Protection

V

OUT

1V/div.

I

L

1A/div.

MP2106-TPC04

MP2106-TPC06

I

L

1A/div.

V

SW

5V/div.

1ms/div.

Short Circuit Recovery

V

OUT

1V/div.

I

L

1A/div.

MP2106-TPC05

MP2106-TPC07

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© 2006 MPS. All Rights Reserved.