MPS MP2105DJ Schematic [ru]
TM
MP2105
1MHz, 800mA Synchronous
Step-Down Converter
The Future of Analog IC Technology
TM
DESCRIPTION
The MP2105 is a 1MHz constant frequency,
current mode, PWM step-down converter. The
device integrates a main switch and a
synchronous rectifier for high efficiency without
an external Schottky diode. It is ideal for
powering portable equipment that runs from a
single cell Lithium-Ion (Li+) battery. The
MP2105 can supply 800mA of load current from
a 2.5V to 6V input voltage. The output voltage
can be regulated as low as 0.6V. The MP2105
can also run at 100% duty cycle for low dropout
applications.
The MP2105 is available in a low profile (1mm)
5-pin, TSOT package.
EVALUATION BOARD REFERENCE
Board Number Dimensions
EV2105DJ-00A 2.0”X x 2.0”Y x 0.5”Z
FEATURES
• High Efficiency: Up to 95%
• 1MHz Constant Switching Frequency
• 800mA Available Load Current
• 2.5V to 6V Input Voltage Range
• Output Voltage as Low as 0.6V
• 100% Duty Cycle in Dropout
• Current Mode Control
• Short Circuit Protection
• Thermal Fault Protection
• <0.1µA Shutdown Current
• Space Saving 5-Pin TSOT23 Package
APPLICATIONS
• Cellular and Smart Phones
• Microprocessors and DSP Core Supplies
• PDAs
• MP3 Players
• Digital Still and Video Cameras
• Portable Instruments
TYPICAL APPLICATION
INPUT
2.5V to 6V
OFF ON
4
1
IN
MP2105
EN
GND
2
SW
FB
“MPS” and “The Future of Analog IC Technology” are Trademarks of Monolithic
Power Systems, Inc.
Efficiency vs
Load Current
100
V
= 3.3V
3
5
OUTPUT
1.8V
800mA
MP2105_TAC_S01
IN
90
80
70
60
50
40
30
EFFICIENCY (%)
20
10
0
10 100 1000
V
= 4.2V
IN
LOAD CURRENT (mA)
MP2105-EC01
MP2105 Rev. 1.2 www.MonolithicPower.com 1
8/19/2005 MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited.
© 2005 MPS. All Rights Reserved.
TM
MP2105 – 1MHz 800mA SYNCHRONOUS STEP-DOWN CONVERTER
PACKAGE REFERENCE
TOP VIEW
1
2
3
C 6 YW
54FB
MP1557_PD01_TSOT23-5
IN
–40°C to +85°C
EN
GND
SW
Part Number* Package Temperature
MP2105DJ TSOT23-5
For Tape & Reel, add suffix –Z (eg. MP2105DJ–Z)
*
For Lead Free, add suffix –LF (eg. MP2105DJ–LF–Z)
ABSOLUTE MAXIMUM RATINGS
(1)
VIN to GND .................................. –0.3V to +6.5V
V
to GND........................... –0.3V to VIN +0.3V
SW
V
, VEN to GND.......................... –0.3V to +6.5V
FB
Junction Temperature.............................+150°C
Lead Temperature ..................................+260°C
Storage Temperature .............–65°C to +150°C
Recommended Operating Conditions
(2)
Supply Voltage VIN............................. 2.5V to 6V
Output Voltage V
.......................... 0.6V to 6V
OUT
Operating Temperature .............–40°C to +85°C
Thermal Resistance
(3)
θ
JA
θJC
TSOT23-5.............................. 220 .... 110.. °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.
ELECTRICAL CHARACTERISTICS
(4)
VIN = VEN = 3.6V, TA = +25°C, unless otherwise noted.
Parameter Symbol Condition Min Typ Max Units
Supply Current VEN = VIN, VFB = 0.65V 440 600 µA
Shutdown Current VEN = 0V, VIN = 6V 0.10 1 µA
IN Undervoltage Lockout
Threshold
IN Undervoltage Lockout
Hysteresis
Regulated FB Voltage VFB
FB Input Bias Current VFB = 0.65V –50 0.5 +50 nA
PFET On Resistance ISW = 100mA 0.42 Ω
NFET On Resistance ISW = –100mA 0.26 Ω
SW Leakage Current
PFET Current Limit
Oscillator Frequency f
Thermal Shutdown Trip
Threshold
EN Trip Threshold –40°C ≤ TA ≤ +85°C 0.3 0.96 1.5 V
EN Input Current VEN = 0V to 6V –1 +1 µA
Notes:
4) 100% production test at +25°C. Specifications over the temperature range are guaranteed by design and characterization.
Rising Edge 2.15 2.30 2.40 V
55 mV
TA = +25°C 0.588 0.600 0.612
–40°C ≤ T
V
= 0V, VIN = 6V,
EN
V
= 0V or 6V
SW
Duty Cycle = 100%,
Current Pulse Width < 1ms
0.85 1.05 1.25 MHz
OSC
≤ +85°C 0.582 0.600 0.618
A
–1 +1 µA
1.2 1.6 2.1 A
145
V
°C
MP2105 Rev. 1.2 www.MonolithicPower.com 2
8/19/2005 MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited.
© 2005 MPS. All Rights Reserved.
TM
MP2105 – 1MHz 800mA SYNCHRONOUS STEP-DOWN CONVERTER
TYPCIAL PERFORMANCE CHARACTERISTICS
VIN = 3.3V, V
= 1.8V, L1 = 4.7µH, C1 = 4.7µF, C3 = 10µF, TA = +25°C, unless otherwise noted.
OUT
100
VIN=3.3V
95
90
)
85
%
80
75
70
65
EFFICIENCY (
60
55
50
10 100 1000
VIN=4.2V
LOAD CURRENT (mA)
Feedback Voltage vs
Temperature
0.603
0.602
0.601
0.600
0.599
0.598
FEEDBACK VOLTAGE (V)
0.597
-20
-40 +200
TEMPERATURE (°C)
+40 +60 +80 +100 -40 +200
MP2105-EC01
MP2105-TPC01
95
VIN=3.3V
90
85
)
%
80
75
70
65
EFFICIENCY (
60
55
50
10 100 1000
VIN=4.2V
LOAD CURRENT (mA)
Switching Frequency vs
Temperature
1.10
1.08
1.06
1.04
1.02
1.00
0.98
0.96
SWITCHING FREQUENCY (MHz)
0.94
-20
TEMPERATURE (°C)
+40 +60 +80 +100
MP2105-EC02
MP2105-TPC02
Load Transient
(I
=0mA to 500mA step)
OUT
V
OUT
100mV/div.
I
OUT
0.5A/div.
MP2105-TPC03
MP2105 Rev. 1.2 www.MonolithicPower.com 3
8/19/2005 MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited.
© 2005 MPS. All Rights Reserved.
10mV/div.
0.2A/div.
2V/div.
Light Load Operation
(I
=0mA)
OUT
V
OUT
I
L
SW
MP2105-TPC04
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