19-4243; Rev 1; 2/09
KIT
ATION
EVALU
BLE
AVAILA
Dual Quick-PWM, Step-Down Controller
with Low-Power LDO, RTC Regulator
General Description
The MAX17101 is a dual Quick-PWM™ step-down
power-supply (SMPS) controller with synchronous rectifi-
cation, intended for main 5V/3.3V power generation in
battery-powered systems. Low-side MOSFET sensing
provides a simple low-cost, highly efficient current sense
for providing valley current-limit protection. Combined
with the output overvoltage and undervoltage protection
features, this current limit ensures robust output supplies.
The 5V/3.3V SMPS outputs can save power by operating
in pulse-skipping mode or in ultrasonic mode to avoid
audible noise. Ultrasonic mode forces the controller to
maintain switching frequencies greater than 20kHz at
light loads.
An internal 100mA linear regulator can be used to
either generate the 5V bias needed for power-up or
other lower power “always-on” suspend supplies. An
independent bypass input allows automatic bypassing
of the linear regulator when the SMPS is active.
This main controller also includes a secondary feed-
back input that triggers an ultrasonic pulse (DL1 turned
on) if the SECFB voltage drops below its threshold volt-
age. This refreshes an external charge pump driven by
DL1 without overcharging the output voltage.
The device includes independent shutdown controls to
simplify power-up and power-down sequencing. To
prevent current surges at startup, the internal voltage
target is slowly ramped up from zero to the final target
over a 1ms period. To prevent the output from ringing
below ground in shutdown, the internal voltage target
is ramped down from its previous value to zero over a
1ms period. Two independent power-good outputs
simplify the interface with external controllers.
The MAX17101 comes in a lead-free 32-pin TQFN
(5mm x 5mm) package and operates in the -40°C to
+85°C temperature range.
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Features
Dual Quick-PWM
Internal 100mA 5V or Adjustable Linear Regulator
Independent LDO Bypass Input
Internal Boost Diodes
Secondary Feedback Input Maintains Charge Pump
3.3V 5mA RTC Power (Always On)
OUT1: 5V or 1.5V Fixed or 0.7V Adjustable
Feedback
OUT2: 3.3V or 1.05V Fixed or Dynamic Adjustable
Dynamic 0 to 2V REFIN2 Input on Second Output
2V ±1% 50µA Reference
6V to 24V Input Range (28V max)
Ultrasonic Mode
Independent SMPS and LDO Enable Controls
Independent SMPS Power-Good Outputs
Minimal Component Count
MAX17101
Ordering Information
PART
MAX17101ETJ+
TEMP RANGE
-40°C to +85°C
PIN-PACKAGE
32 Thin QFN-EP*
+Denotes
a lead-free/RoHS-compliant package.
*EP
= Exposed pad.
Pin Configuration
PGND
SECFB
AGND
DL2
DL1
18
V
DD
TOP VIEW
24
LX2
25
DH2
26
ON2
27
PGOOD2
28
SKIP
29
OUT2
30
ILIM2
31
REFIN2
32
BST2
23
22
21
20
19
17
16
15
14
13
LX1
DH1
ON1
PGOOD1
ILIM1
FB1
OUT1
BYP
Applications
Notebook Computers
Main System Supply (5V and 3.3V Supplies)
Graphic Cards
DDR1, DDR2, DDR3 Power Supplies
Game Consoles
Low-Power I/O and Chipset Supplies
Two to Four Li+ Cells Battery-Powered Devices
PDAs and Mobile Communicators
Telecommunication
Quick-PWM is a trademark of Maxim Integrated Products, Inc.
MAX17101
BST1
12
11
10
9
8
LDOSEL
+
1
REF
2
TON
3
V
CC
4
ONLDO
5
RTC
6
IN
7
LDO
THIN QFN
A "+" SIGN FIRST-PIN INDICATOR DENOTES A LEAD-FREE PACKAGE.
________________________________________________________________
Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
Dual Quick-PWM, Step-Down Controller
with Low-Power LDO, RTC Regulator
MAX17101
ABSOLUTE MAXIMUM RATINGS
IN, ONLDO to GND ................................................-0.3V to +28V
V
DD
, V
CC
to GND .....................................................-0.3V to +6V
RTC, LDO to GND ....................................................-0.3V to +6V
OUT_ to GND ...........................................................-0.3V to +6V
ON1, ON2 to GND....................................................-0.3V to +6V
PGOOD_ to GND........................................-0.3V to (V
CC
+ 0.3V)
REF, ILIM_, TON,
SKIP
to GND ..................-0.3V to (V
CC
+ 0.3V)
FB1, REFIN2, LDOSEL to GND ................................-0.3V to +6V
SECFB to GND .........................................................-0.3V to +6V
BYP to GND..............................................-0.3V to (V
LDO
+ 0.3V)
GND to PGND .......................................................-0.3V to +0.3V
DL_ to PGND ..............................................-0.3V to (V
DD
+ 0.3V)
BST_ to GND ..........................................................-0.3V to +34V
BST_ to V
DD
............................................................-0.3V to +28V
DH1 to LX1 ..............................................-0.3V to (V
BST1
+ 0.3V)
BST1 to LX1..............................................................-0.3V to +6V
DH2 to LX2 ..............................................-0.3V to (V
BST2
+ 0.3V)
BST2 to LX2..............................................................-0.3V to +6V
LDO, RTC, REF Short Circuit to GND.........................Momentary
RTC Current Continuous.....................................................+5mA
LDO Current (Internal Regulator)
Continuous..................................................................+100mA
LDO Current (Switched Over) Continuous .....................+200mA
Continuous Power Dissipation (T
A
= +70°C)
32-Pin 5mm x 5mm TQFN
(derate 34.5mW/°C above +70°C) .................................2.76W
Operating Temperature Range ...........................-40°C to +85°C
Junction Temperature ......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
(Circuit of Figure 1, no load on LDO, RTC, OUT1, OUT2, and REF, V
IN
= 12V, V
DD
= V
CC
= V
SECFB
= 5V, V
REFIN2
= 1.0V, BYP =
LDOSEL = GND, ONLDO = IN, ON1 = ON2 = V
CC
,
T
A
= 0°C to +85°C,
unless otherwise noted. Typical values are at T
A
= +25°C.)
PARAMETER
INPUT SUPPLIES
IN Standby Supply Current
IN Shutdown Supply Current
I
IN(STBY)
I
IN(SHDN)
V
IN
= 6V to 24V, ON1 = ON2 = GND,
ONLDO = V
CC
V
IN
= 4.5V to 24V,
ON1 = ON2 = ONLDO = GND
ON1 = ON2 = REFIN2 = V
CC
,
SKIP
= FB1 = GND,
V
OUT2
= 3.5V, V
OUT1
= 5.3V
ON1 = ON2 = REFIN2 = V
CC
,
SKIP
= FB1 = GND,
V
OUT2
= 3.5V, V
OUT1
= 5.3V
5V preset output: FB1 = GND,
V
IN
= 12V,
SKIP
= V
CC
1.5V preset output: FB1 = V
CC
(5V),
V
IN
= 12V,
SKIP
= V
CC
Adjustable feedback output,
V
IN
= 12V,
SKIP
= V
CC
Low
FB1 Dual Mode™ Threshold
Voltage Levels
FB1 Input Bias Current
I
FB1
High
V
FB1
= 0.8V, T
A
= +25°C
85
50
175
70
μA
μA
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
IN Supply Current
I
IN
0.1
0.2
mA
V
CC
Supply Current
PWM CONTROLLERS
I
CC
1.0
1.5
mA
4.925
1.482
0.690
0.7
0.04
V
CC
-
1.6V
-0.2
5.00
1.50
0.700
5.075
1.518
0.710
5.5
0.110
V
CC
-
0.7V
+0.2
V
μA
V
V
OUT1 Output-Voltage Accuracy
(Note 1)
V
OUT1
V
FB1
OUT1 Voltage-Adjust Range
Dual Mode is a trademark of Maxim Integrated Products, Inc.
2
_______________________________________________________________________________________
Dual Quick-PWM, Step-Down Controller
with Low-Power LDO, RTC Regulator
ELECTRICAL CHARACTERISTICS (continued)
(Circuit of Figure 1, no load on LDO, RTC, OUT1, OUT2, and REF, V
IN
= 12V, V
DD
= V
CC
= V
SECFB
= 5V, V
REFIN2
= 1.0V, BYP =
LDOSEL = GND, ONLDO = IN, ON1 = ON2 = V
CC
,
T
A
= 0°C to +85°C,
unless otherwise noted. Typical values are at T
A
= +25°C.)
PARAMETER
SYMBOL
CONDITIONS
3.3V preset output: REFIN2 = V
CC
(5V),
V
IN
= 12V,
SKIP
= V
CC
1.05V preset output: REFIN2 = RTC (3.3V),
V
IN
= 12V,
SKIP
= V
CC
Tracking output: V
REFIN2
= 1.1V,
V
IN
= 12V,
SKIP
= V
CC
MIN
3.255
1.038
1.09
0.8
0
I
REFIN2
V
REFIN2
= 2.2V, T
A
= +25°C
V
REFIN2
= 0V, T
A
= +25°C
Low (REFIN2 = RTC)
High (REFIN2 = V
CC
)
Either SMPS,
SKIP
= V
CC
, I
LOAD
= 0 to 5A
Load Regulation Error
Line Regulation Error
DH1 On-Time
t
ON1
Either SMPS,
SKIP
= REF, I
LOAD
= 0 to 5A
Either SMPS,
SKIP
= GND, I
LOAD
= 0 to 5A
Either SMPS, V
IN
= 6V to 24V
V
IN
= 12V,
V
OUT1
= 5.0V
(Note 2)
V
IN
= 12V,
V
OUT2
= 3.3V
(Note 2)
(Note 2)
Rising/falling edge on ON1 or ON2 (preset)
Rising/falling edge on ON2 (REFIN2 ADJ)
Rising edge on REFIN2
20
1.94
V
SECFB
= 2.2V, T
A
= +25°C
V
IN
= 24V, LDOSEL = BYP = GND,
0 < I
LDO
< 100mA
V
IN
= 24V, LDOSEL = V
CC
, BYP = GND,
0 < I
LDO
< 100mA
LDOSEL low
LDOSEL high
-0.2
TON = GND or REF
(400kHz)
TON = V
CC
(200kHz)
TON = GND (500kHz)
TON = REF or V
CC
(300kHz)
833
895
-0.1
-0.5
2.2
V
CC
-
1.0V
-0.1
-1.7
-1.5
0.005
1052
2105
555
925
300
1
1
8
27
2.0
2.06
+0.2
1017
400
ns
ns
ms
mV/μs
mV/μs
kHz
V
μA
1209
%/V
ns
%
TYP
3.30
1.050
1.10
MAX
3.345
1.062
1.11
2.0
2
+0.1
+0.1
3.0
V
CC
-
0.4V
V
V
V
μA
V
UNITS
MAX17101
OUT2 Output-Voltage Accuracy
(Note 1)
V
OUT2
OUT2 Voltage-Adjust Range
REFIN2 Voltage-Adjust Range
REFIN2 Input Bias Current
REFIN2 Dual Mode Threshold
Voltage Levels
DH2 On-Time
Minimum Off-Time
Soft-Start/Stop Slew Rate
Soft-Start/Stop Slew Rate
Dynamic REFIN2 Slew Rate
SECFB Threshold Voltage
SECFB Input Bias Current
LINEAR REGULATOR (LDO)
t
ON2
t
OFF(MIN)
t
SS
t
SS
t
DYN
V
SECFB
I
SECFB
Ultrasonic Operating Frequency f
SW(USONIC)
SKIP
= open (REF)
4.90
3.23
0.1
V
CC
-
0.9V
5.0
3.3
0.15
5.10
V
3.37
0.2
V
LDO Output-Voltage Accuracy
V
LDO
LDOSEL Dual Mode Threshold
Voltage Levels
_______________________________________________________________________________________
3
Dual Quick-PWM, Step-Down Controller
with Low-Power LDO, RTC Regulator
MAX17101
ELECTRICAL CHARACTERISTICS (continued)
(Circuit of Figure 1, no load on LDO, RTC, OUT1, OUT2, and REF, V
IN
= 12V, V
DD
= V
CC
= V
SECFB
= 5V, V
REFIN2
= 1.0V, BYP =
LDOSEL = GND, ONLDO = IN, ON1 = ON2 = V
CC
,
T
A
= 0°C to +85°C,
unless otherwise noted. Typical values are at T
A
= +25°C.)
PARAMETER
LDO Short-Circuit Current
LDO Regulation Reduction/
Bypass Switchover Threshold
LDO Bypass Switchover
Threshold
LDO Bypass Switchover
Startup Timeout
LDO Bypass Switch Resistance
V
CC
Undervoltage-Lockout
(UVLO) Threshold
Thermal-Shutdown Threshold
t
BYP
SYMBOL
I
ILIM(LDO)
LDO = GND
With respect to the LDO voltage,
falling edge of BYP
With respect to the LDO voltage,
rising edge of BYP
Rising edge of BYP to bypass gate pulled
low
LDO to BYP, V
BYP
= 5V (Note 4)
Falling edge of V
CC
,
V
UVLO(VCC)
PWM disabled below this threshold
Rising edge of V
CC
T
SHDN
Hysteresis = 10°C
ON1 = ON2 = GND, V
IN
= 6V to 24V,
0 < I
RTC
< 5mA
ON1 = ON2 = ONLDO = GND,
V
IN
= 6V to 24V, 0 < I
RTC
< 5mA
RTC = GND
V
CC
= 4.5V to 5.5V, I
REF
= 0
I
REF
= -20μA to +50μA
3.3V ALWAYS-ON LINEAR REGULATOR (RTC)
3.23
3.16
5
1.980
-10
1.95
2.00
2.020
+10
3.33
3.43
V
3.50
mA
V
mV
V
3.8
CONDITIONS
MIN
100
-11.0
-8.5
-6.5
500
1.2
4.0
4.2
+160
°C
4.5
4.3
V
TYP
MAX
260
-6.0
UNITS
mA
%
%
μs
RTC Output-Voltage Accuracy
V
RTC
RTC Short-Circuit Current
REFERENCE (REF)
Reference Voltage
Reference Load Regulation
REF Lockout Voltage
OUT1 FAULT DETECTION
OUT1 Overvoltage Trip
Threshold
OUT1 Overvoltage
Fault-Propagation Delay
OUT1 Undervoltage Protection
Trip Threshold
OUT1 Output-Undervoltage
Fault-Propagation Delay
PGOOD1 Lower Trip Threshold
PGOOD1 Propagation Delay
PGOOD1 Output Low Voltage
PGOOD1 Leakage Current
I
ILIM(RTC)
V
REF
V
REF
V
REF(UVLO)
Rising edge, 350mV (typ) hysteresis
V
OVP(OUT1)
With respect to error-comparator threshold
t
OVP
FB1 forced 50mV above trip threshold
12
16
10
20
%
μs
V
UVP(OUT1)
With respect to error-comparator threshold
t
UVP
With respect to error-comparator threshold,
falling edge, hysteresis = 1%
t
PGOOD1
FB1 forced 50mV beyond PGOOD1 trip
threshold, falling edge
V
FB1
= 0.56V (PGOOD1 low impedance),
I
SINK
= 4mA
I
PGOOD1
V
FB1
= 0.70V (PGOOD1 high impedance),
PGOOD1 forced to 5.5V
65
70
10
75
%
μs
-20
-16
10
-12
%
μs
0.3
1
V
μA
4
_______________________________________________________________________________________
Dual Quick-PWM, Step-Down Controller
with Low-Power LDO, RTC Regulator
ELECTRICAL CHARACTERISTICS (continued)
(Circuit of Figure 1, no load on LDO, RTC, OUT1, OUT2, and REF, V
IN
= 12V, V
DD
= V
CC
= V
SECFB
= 5V, V
REFIN2
= 1.0V, BYP =
LDOSEL = GND, ONLDO = IN, ON1 = ON2 = V
CC
,
T
A
= 0°C to +85°C,
unless otherwise noted. Typical values are at T
A
= +25°C.)
PARAMETER
OUT2 FAULT DETECTION
OUT2 Overvoltage Trip
Threshold
OUT2 Overvoltage
Fault-Propagation Delay
OUT2 Undervoltage Protection
Trip Threshold
OUT2 Overvoltage
Fault-Propagation Delay
OUT2 Output Undervoltage
Fault-Propagation Delay
PGOOD2 Lower Trip Threshold
PGOOD2 Propagation Delay
PGOOD2 Output-Low Voltage
PGOOD2 Leakage Current
CURRENT LIMIT
ILIM_ Adjustment Range
ILIM_ Current
Valley Current-Limit Threshold
(Adjustable)
Current-Limit Threshold
(Negative)
Ultrasonic Current-Limit
Threshold
Current-Limit Threshold
(Zero Crossing)
V
ILIM
I
ILIM
V
VALLEY
V
NEG
V
NEG(US)
V
ZX
V
AGND
- V
LX
_
R
ILIM
_ = 100k
R
ILIM
_ = 200k
40
87
0.2
5
50
100
-120
25
1
60
113
2.0
V
μA
mV
%
mV
mV
I
PGOOD2
t
PGOOD2
V
OVP(OUT2)
t
OVP
With respect to error-comparator threshold
Minimum overvoltage threshold
OUT2 forced 50mV above trip threshold
65
12
16
0.7
10
70
10
10
-20
-16
10
0.3
1
-12
75
20
%
V
μs
%
μs
μs
%
μs
V
μA
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
MAX17101
V
UVP(OUT2)
With respect to error-comparator threshold
t
OVP
t
UVP
OUT2 forced 50mV above trip threshold
OUT2 forced 50mV below trip threshold
With respect to error-comparator threshold,
falling edge, hysteresis = 2%
OUT2 forced 50mV beyond PGOOD1 trip
threshold, falling edge
V
OUT2
= V
REFIN2
- 150mV (PGOOD2 low
impedance), I
SINK
= 4mA
OUT2 = REFIN2 (PGOOD2 high impedance),
PGOOD2 forced to 5.5V, T
A
= +25°C
With respect to valley current-limit threshold,
SKIP
= V
CC
V
OUT1
= V
OUT2
= V
FB1
= 0.77V, V
REFIN2
= 0.70V
V
AGND
- V
LX
_,
SKIP
= GND or OPEN/REF
_______________________________________________________________________________________
5