MIC2165
Adaptive On-Time DC-DC Controller
Featuring HyperLight Load
®
Hyper Speed Control™ Family
General Description
The Micrel MIC2165 is a synchronous adaptive on-time
buck controller targeting high-performance, cost-sensitive
applications such as set-top boxes, gateways, routers,
computing
peripherals,
and
telecom/networking
equipment.
The MIC2165 operates over a supply range of 4.5V to
28V. It has an internal linear regulator which provides a
regulated 5V supply to power the internal control circuitry.
MIC2165 operates at a constant 600kHz switching
frequency and can be used to drive up to 25A of output
current. The output voltage is adjustable from 0.8V to
5.5V.
A unique Hyper Speed Control™ architecture enables
ultra-fast transient response while reducing the output
capacitance and also makes High V
IN
/Low V
OUT
operation
possible.
A UVLO feature is provided to ensure proper operation
under power-sag conditions to prevent the external power
MOSFET from over heating. Also, a soft start feature is
provided to reduce the inrush current. Short current
sensing on the bottom MOSFET with hiccup mode current
limiting ensures protection in case of an output short
circuit. Further, the MIC2165 includes an EN pin to shut
down the converter and a Power Good (PGOOD) pin to
allow simple sequencing.
The MIC2165 is available in a 10-pin MSOP ePad
package with a junction operating temperature ranging
from –40°C to +125°C. All support documentation can be
found on Micrel’s web site at:
www.micrel.com.
Features
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Hyper Speed Control™ architecture enables
High V
IN
Low V
OUT
operation (V
IN
=28V & V
OUT
=0.8V)
Small output capacitance
HyperLight Load
®
Efficiency
Built-in 5V regulator for single-supply operation
Any Capacitor
TM
stable
- Zero ESR to high ESR
Power-Good output
Input voltage range: 4.5V to 28V
5μA typical shutdown current
25A output current drive capability
Adjustable output from 0.8V to 5.5V with ±1% FB
Accuracy
600kHz switching frequency
Internal 5ms digital Soft Start
Thermal shutdown and hiccup current-limit protection
No external current-sense resistor required
Safe start-up into pre-biased loads
10-pin MSOP ePad package
–40°C to +125°C junction temperature range
Applications
•
•
•
•
Set-top box, gateways, routers and DSL modems
Printers, scanners, graphic and video cards
Servers, PCs and processor core supply
Low-Voltage Distributed Power
Typical Application
12V to 3.3V Efficiency
100
90
80
EFFICIENCY (%)
70
60
50
40
30
20
10
0
0.01
0.10
1.00
10.00
MIC2165 Adjustable Output 600kHz Buck Converter
MLF and
MicroLeadFrame
are registered trademarks of Amkor Technology, Inc.
HyperLight Load is a registered trademark of Micrel, Inc.
Hyper Speed Control and Any Capacitor are trademarks of Micrel, Inc.
OUTPUT CURRENT (A)
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (
408
) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
September 2010
M9999-092410-E
Micrel, Inc.
MIC2165
Ordering Information
Part Number
MIC2165YMME
Voltage
Adj.
Switching Frequency
600kHz
Junction Temp. Range
–40° to +125°C
Package
10-pin ePad MSOP
Lead Finish
Pb-Free
Pin Configuration
10-Pin ePad MSOP (MME)
Pin Description
Pin
Number
1
2
3
4
Pin Name
FB
PGOOD
Pin Function
Feedback (Input): Input to the transconductance amplifier of the control loop. The FB pin is regulated to
0.8V. A resistor divider connecting the output to FB is used to set the desired output voltage.
Power Good (Output): Open Drain Output. The PGOOD pin is externally tied with a resistor to VDD.
High output when V
OUT
>90% nominal.
Enable (Input): A logic level control of the output. The EN pin is CMOS-compatible. Logic high = enable,
logic low = shutdown. In the off state, supply current of the device is greatly reduced (typically 5µA). The
EN pin should not be left open. Connect to VIN if sequencing not required.
Supply Voltage: Input voltage for the internal +5V linear regulator. The VIN operating voltage range is
from 4.5V to 28V. A 0.1µF capacitor between VIN and the ground is required.
5V Internal Linear Regulator (Output): VDD is the external MOSFET gate drive supply voltage and an
internal supply bus for the IC. VDD is created by internal LDO from VIN. When VIN <+5.5V, VDD Should
be tied to VIN. A 2.2µF (minimum) ceramic capacitor from VDD to GND
is
recommended for clean
operation.
Low-Side Gate Drive (Output): High-current driver output for external low-side MOSFET. The DL driving
voltage swings from ground to VDD.
Power Ground. PGND is the ground path for the MIC2165 buck converter power stage. The PGND pin
connects to the sources of low-side N-Channel MOSFETs, the negative terminals of input capacitors,
and the negative terminals of output capacitors. The loop for the power ground should be as small as
possible and separate from the Signal ground (GND) loop.
High-Side Gate Drive (Output): High-current driver output for external high-side MOSFET. The DH
driving voltage is floating on the switch node voltage (SW). It swings from ground-to-VDD minus the
diode drop.
Switch Node (Input): High current output driver return. The SW pin connects directly to the switch node.
Due to the high speed switching on this pin, the SW pin should be routed away from sensitive nodes.
9
SW
Current-Sense Input (Input): SW pin also senses the current by monitoring the voltage across the low-
side MOSFET during OFF-time. The current sensing is necessary for short circuit protection and zero
current cross comparator. In order to sense the current accurately, connect the low-side MOSFET drain
to SW using a Kelvin connection.
Boost (Output): Bootstrapped voltage to the high-side N-channel MOSFET driver. A Schottky diode is
connected between the VDD pin and the BST pin. A boost capacitor of 0.1μF is connected between the
BST pin and the SW pin. Adding a small resistor at BST pin can slow down the turn-on time of high-side
N-Channel MOSFETs.
Thermal Pad and Signal ground. GND is the ground path for VDD and the control circuitry. The loop for
the signal ground should be separate from the power ground (PGND) loop.
EN
VIN
VDD
5
6
DL
7
PGND
8
DH
10
BST
EP
GND
September 2010
2
M9999-092410-E
Micrel, Inc.
MIC2165
Absolute Maximum Ratings
(1)
V
IN
to GND .....................................................
−0.3V
to +29V
V
DD
, V
FB
, V
PGOOD
to GND .................................
−0.3V
to +6V
V
BST
to V
SW
......................................................
−0.3V
to +6V
V
BST
to GND ..................................................
−0.3V
to +35V
V
EN
to GND............................................
−0.3V
to (V
IN
+0.3V)
V
DH
to V
SW
.........................................−0.3V to (V
BST
+ 0.3V)
V
DL
to GND .........................................
−0.3V
to (V
DD
+ 0.3V)
PGND to GND ..............................................
−0.3V
to +0.3V
Junction Temperature .............................................. +150°C
Storage Temperature (T
S
).........................−65°C to +150°C
Lead Temperature (soldering, 10sec)........................ 260°C
Operating Ratings
(2)
Supply Voltage (V
IN
).......................................... 4.5V to 28V
Enable Input Voltage (V
EN
)..................................... 0V to V
IN
Junction Temperature (T
J
) ........................
−40°C
to +125°C
Package Thermal Resistance
(3)
MSOP-10L ePad (θ
JA
) ......................................77°C/W
MSOP-10L ePad (θ
JC
) ......................................10°C/W
Electrical Characteristics
V
IN
= V
EN
= 12V; V
BST
– V
SW
= 5V; T
J
= 25°C, unless noted.
Bold
values indicate
−40°C
≤
T
J
≤
125°C.
Parameter
Power Input Supply
Input Voltage Range (V
IN
)
Quiescent Supply Current
Shutdown Current
VDD Supply
VDD Output Voltage
VDD UVLO Threshold
VDD UVLO Hysteresis
Dropout Voltage (V
IN
−
V
DD
)
DC-DC Controller
Output-Voltage Adjust Range (V
OUT
)
Reference
T
J
= 25°C
Feedback Regulation Voltage
0°C
≤
T
J
≤
85°C
−40°C
≤
T
J
≤
125°C
Load Regulation
Line Regulation
FB Bias Current
Enable Control
(5)
Enable Logic Level High
Enable Logic Level Low
Enable Hysteresis
Enable Bias Current
V
EN
= 12V
100
6
30
1.6
0.6
V
V
mV
µA
I
OUT
= 2A to 10A (Continuous Mode)
Depends on external components
V
IN
= 4.5V to 28V
Depends on external components
V
FB
= 0.8V
0.792
0.788
0.784
0.25
0.25
50
500
0.8
0.808
0.812
0.816
V
V
V
%
%
nA
0.8
5.5
V
I
DD
= 25mA
V
IN
= 7V to 28V, I
DD
= 40mA
V
DD
rising
4.8
3.7
5.2
4.2
400
380
600
5.4
4.5
V
V
mV
mV
V
FB
= 1.5V (non-switching)
V
EN
= 0V
4.5
450
5
28
750
10
V
µA
µA
Condition
Min.
Typ.
Max.
Units
September 2010
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Micrel, Inc.
MIC2165
Electrical Characteristics (Continued)
V
IN
= V
EN
= 12V; V
BST
– V
SW
= 5V; T
J
= 25°C, unless noted.
Bold
values indicate
−40°C
≤
T
J
≤
125°C.
Parameter
Condition
Min.
On Timer
Switching Frequency
Minimum Off-Time
Maximum Duty Cycle
Minimum Duty Cycle
Bottom FET Active
Results from Switching Frequency and
Minimum Off-Time
V
FB
= 1.0V
450
200
600
300
82
0
750
400
kHz
ns
%
%
Typ.
Max.
Units
Zero
Crossing Comparator Offset
Short-Current Protection
Current-Limit Threshold
Short-Circuit Current
FET Drives
DH, DL Output Low Voltage
DH, DL Output High Voltage
I
SINK
= 10mA
I
SOURCE
= 10mA
Pull Up, I
SOURCE
= 20mA
Pull Down, I
SINK
= 20mA
Pull Up, I
SOURCE
= 20mA
Pull Down, I
SINK
= 20mA
V
SW
= V
BST
= 0
Sweep V
FB
from Low to High
Sweep V
FB
from High to Low
Sweep V
FB
from Low to High
V
FB
<0.9
×
V
NOM
, I
PGOOD
= 1mA
V
FB
= 0.79V
V
FB
= 0V
-16
98
24
0.5
133
48
16
182
72
0.1
mV
mV
mV
V
V
V
DD
−
0.1V
or
V
BST
−
0.1V
2
1.5
2
1
3
3
3
2
30
90
6.0
100
70
DH On-Resistance
DL On-Resistance
SW, BST Leakage Current
Power Good (PGOOD)
PGOOD Threshold Voltage
PGOOD Hysteresis
PGOOD Delay Time
PGOOD Low Voltage
Thermal Protection
Over-temperature Shutdown
Over-temperature Shutdown Hysteresis
Notes:
1.
2.
3.
4.
5.
Ω
Ω
µA
%V
OUT
%V
OUT
µs
mV
85
95
200
T
J
Rising
160
15
°C
°C
Exceeding the absolute maximum rating may damage the device.
The device is not guaranteed to function outside its operating rating.
The maximum allowable power dissipation of any T
A
(ambient temperature) is P
D(max)
= (T
J(max)
– T
A
) /
θ
JA
. Exceeding the maximum allowable power
dissipation will result in excessive die temperature, and the regulator will go into thermal shutdown.
Devices are ESD sensitive. Handling precautions recommended. Human body model, 1.5k in series with 100pF.
Enable pin should not be left open.
September 2010
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M9999-092410-E
Micrel, Inc.
MIC2165
Typical Characteristics
12V to 3.3V Efficiency
100
90
80
12V to 1.2V Efficiency
100
90
Output Voltage vs. Load
1.30
1.28
60
50
40
30
20
10
0
0.01
EFFICIENCY (%)
EFFICIENCY (%)
70
70
60
50
40
30
20
10
0
0.01
OUTPUT VOLTAGE (V)
80
1.26
1.24
1.22
1.20
1.18
1.16
1.14
1.12
1.10
V
IN
= 12V
V
OUT
= 1.2V
0.10
1.00
10.00
0.10
1.00
10.00
0
2
4
6
8
10
OUTPUT CURRENT (A)
OUTPUT CURRENT (A)
OUTPUT CURRENT (A)
1.30
1.28
Output Voltage
vs. Input Voltage
0.812
Feedback Voltage
vs. Temperature
SWITCHING FREQUENCY (kHz)
750
720
690
660
630
600
570
540
510
480
450
Switching Frequency vs. Load
(Continuous Mode)
OUTPUT VOLTAGE (V)
1.26
1.24
1.22
1.20
1.18
1.16
1.14
1.12
1.10
4
8
12
16
20
24
28
I
OUT
= 10A
I
OUT
= 100mA
FEEDBACK VOLTAGE (V)
0.808
0.804
0.800
0.796
0.792
V
IN
= 12V
V
OUT
= 2.5V
0.788
-40
0
40
80
120
0
2
4
6
8
10
INPUT VOLTAGE (V)
TEMPERATURE (ºC)
OUTPUT CURRENT (A)
750
Switching Frequency
vs. Temperature
SWITCHING FREQUENCY (kHz)
750
720
690
660
630
600
570
540
510
480
450
Switching Frequency
vs. Input Voltage
CURRENT LIMIT THRESHOLD
(mV)
I
OUT
= 5A
160
140
120
100
80
60
40
20
0
Current Limit Threshold vs.
Feedback Voltage Percentage
SWITCHING FREQUENCY (kHz)
720
690
660
630
600
570
540
510
480
450
-40
0
40
80
120
V
IN
= 12V
V
OUT
= 2.5V
0
20
40
60
80
100
4
8
12
16
20
24
28
TEMPERATURE (°C)
INPUT VOLTAGE (V)
FEEDBACK VOLTAGE PERCENTAGE (%)
September 2010
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M9999-092410-E