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MAX17101
User Manual
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Rainbow Electronics MAX17101 User Manual

MAX17101
Dual Quick-PWM, Step-Down Controller
with Low-Power LDO, RTC Regulator
________________________________________________________________
Maxim Integrated Products
1
Ordering Information
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.
General Description
The MAX17101 is a dual Quick-PWM™ step-down power-supply (SMPS) controller with synchronous rectifi­cation, 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 feed­back input that triggers an ultrasonic pulse (DL1 turned on) if the SECFB voltage drops below its threshold volt­age. 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.
Features
Applications
+
Denotes a lead-free/RoHS-compliant package.
*
EP = Exposed pad.
o Dual Quick-PWM o Internal 100mA 5V or Adjustable Linear Regulator o Independent LDO Bypass Input o Internal Boost Diodes o Secondary Feedback Input Maintains Charge Pump o 3.3V 5mA RTC Power (Always On) o OUT1: 5V or 1.5V Fixed or 0.7V Adjustable
Feedback
o OUT2: 3.3V or 1.05V Fixed or Dynamic Adjustable o Dynamic 0 to 2V REFIN2 Input on Second Output o 2V ±1% 50µA Reference o 6V to 24V Input Range (28V max) o Ultrasonic Mode o Independent SMPS and LDO Enable Controls o Independent SMPS Power-Good Outputs o Minimal Component Count
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
MAX17101
THIN QFN
TOP VIEW
A "+" SIGN FIRST-PIN INDICATOR DENOTES A LEAD-FREE PACKAGE.
29
30
28
27
12
11
13
TON
ONLDO
RTC
IN
LDO
14
REF
DL2
AGND
SECFB
BST2
V
DD
DL1
12
PGOOD2
4567
2324 22 20 19 18
SKIP
OUT2
ON1
PGOOD1
ILIM1
FB1
V
CC
PGND
3
21
31
10
ILIM2
OUT1
32
9
REFIN2
+
BYP
ON2
26
15
DH1
DH2
25
16
LX1
LDOSEL
BST1
8
17
LX2
Pin Configuration
Quick-PWM is a trademark of Maxim Integrated Products, Inc.
EVALUATION KIT
AVAILABLE
PART TEMP RANGE PIN-PACKAGE
MAX17101ETJ+ -40°C to +85°C 32 Thin QFN-EP*
MAX17101
Dual Quick-PWM, Step-Down Controller with Low-Power LDO, RTC Regulator
2 _______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(Circuit of Figure 1, no load on LDO, RTC, OUT1, OUT2, and REF, VIN= 12V, VDD= VCC= V
SECFB
= 5V, V
REFIN2
= 1.0V, BYP =
LDOSEL = GND, ONLDO = IN, ON1 = ON2 = V
CC
, TA= 0°C to +85°C, unless otherwise noted. Typical values are at TA= +25°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.
IN, ONLDO to GND ................................................-0.3V to +28V
V
DD
, VCCto 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
Dual Mode is a trademark of Maxim Integrated Products, Inc.
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
INPUT SUPPLIES
IN Standby Supply Current I
IN Shutdown Supply Current I
IN Supply Current I
VCC Supply C urrent I
PWM CONTROLLERS
OUT1 Output-Voltage Accuracy (Note 1)
OUT1 Voltage-Adjust Range 0.7 5.5 V
FB1 Dual Mode™ Threshold Voltage Leve ls
FB1 Input B ias Current I
IN(STBY)
IN(SHDN)
IN
CC
V
OUT1
V
FB1
FB1
VIN = 6V to 24V, ON1 = ON2 = GND, ONLDO = V
VIN = 4.5V to 24V, ON1 = ON2 = ONLDO = GND
ON1 = ON2 = REFIN2 = VCC, SKIP = FB1 = GND,
= 3.5V, V
V
OUT2
ON1 = ON2 = REFIN2 = VCC, SKIP = FB1 = GND,
= 3.5V, V
V
OUT2
5V preset output: FB1 = GND,
= 12V, SKIP = V
V
IN
1.5V preset output: FB1 = VCC (5V),
= 12V, SKIP = V
V
IN
Adju stab le feedback output,
= 12V, SKIP = V
V
IN
Low 0.04 0.110
High
V
= 0.8V, TA = +25°C -0.2 +0.2 μA
FB1
CC
OUT1
OUT1
= 5.3V
= 5.3V
CC
CC
CC
85 175 μA
50 70 μA
0.1 0.2 mA
1.0 1.5 mA
4.925 5.00 5.075
1.482 1.50 1.518
0.690 0.700 0.710
V
-
CC
1.6V
VCC -
0.7V
V
V
MAX17101
Dual Quick-PWM, Step-Down Controller
with Low-Power LDO, RTC Regulator
_______________________________________________________________________________________ 3
ELECTRICAL CHARACTERISTICS (continued)
(Circuit of Figure 1, no load on LDO, RTC, OUT1, OUT2, and REF, VIN= 12V, VDD= VCC= V
SECFB
= 5V, V
REFIN2
= 1.0V, BYP =
LDOSEL = GND, ONLDO = IN, ON1 = ON2 = V
CC
, TA= 0°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C.)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
3.3V preset output: REFIN2 = VCC (5V), V
= 12V, SKIP = V
OUT2 Output-Voltage Accuracy (Note 1)
V
OUT2
IN
1.05V preset output: REFIN2 = RTC (3.3V), V
= 12V, SKIP = V
IN
Tracking output: V V
= 12V, SKIP = V
IN
CC
CC
REFIN2
CC
= 1.1V,
OUT2 Voltage-Adjust Range 0.8 2.0 V
REFIN2 Voltage-Adju st Range 0 2 V
V
= 2.2V, TA = +25°C -0.1 +0.1
REFIN2 Input Bias Current I
REFIN2 Dual Mode Threshold Voltage Leve ls
Load Regulation Error
REFIN2
REFIN2
V
= 0V, TA = +25°C -0.5 +0.1
REFIN2
Low (REFIN2 = RTC) 2.2 3.0
High (REFIN2 = V
Either SMPS, SKIP = VCC, I Either SMPS, SKIP = REF, I Either SMPS, SKIP = GND, I
CC
)
= 0 to 5A -0.1
LOAD
= 0 to 5A -1.7
LOAD
= 0 to 5A -1.5
LOAD
Line Regulation Error Either SMPS, VIN = 6V to 24V 0.005 %/V
TON = GND or REF (400kHz)
TON = V
(200kH z) 2105
CC
TON = GND (500kH z) 555
TON = REF or V
CC
(300kHz)
DH1 On-Time t
DH2 On-Time t
Minimum Off-Time t
OFF(MIN)
Soft-Start/Stop Slew Rate t
Soft-Start/Stop Slew Rate t
Dynamic REFIN2 Slew Rate t
Ultrasonic Operating Frequency f
SW(USONIC)
SECFB Threshold Voltage V
SECFB Input Bias Current I
VIN = 12V,
ON1
V
OUT1
(Note 2)
VIN = 12V, V
ON2
OUT2
(Note 2)
(Note 2) 300 400 ns
SS
SS
DYN
Risi ng/falling edge on ON1 or ON2 (preset)
Risi ng/falling edge on ON2 (REFIN2 AD J)
Risi ng edge on REFIN2 8 mV/μs SKIP = open (REF) 20 27 kHz
SECFB
SECFB VSECFB
1.94 2.0 2.06 V
= 5.0V
= 3.3V
= 2.2V, TA = +25°C -0.2 +0.2 μA
LINEAR REGULATOR (LDO)
VIN = 24V, LDOSEL = BYP = GND,
LDO Output-Voltage Accuracy V
LDOSEL Dual Mode Threshold Voltage Leve ls
LDO
0 < I VIN = 24V, LDOSEL = VCC, BYP = GND,
0 < I
LDOSEL low 0.1 0.15 0.2
LDOSEL high
< 100mA
LDO
< 100mA
LDO
3.255 3.30 3.345
1.038 1.050 1.062
V
1.09 1.10 1.11
μA
V
CC
1.0V
-
V
CC
0.4V
V
-
%
895 1052 1209
833 925 1017
1
ms
ns
ns
1 mV/μs
4.90 5.0 5.10 V
3.23 3.3 3.37
V
-
CC
V
0.9V
MAX17101
Dual Quick-PWM, Step-Down Controller with Low-Power LDO, RTC Regulator
4 _______________________________________________________________________________________
ELECTRICAL CHARACTERISTICS (continued)
(Circuit of Figure 1, no load on LDO, RTC, OUT1, OUT2, and REF, VIN= 12V, VDD= VCC= V
SECFB
= 5V, V
REFIN2
= 1.0V, BYP =
LDOSEL = GND, ONLDO = IN, ON1 = ON2 = V
CC
, TA= 0°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C.)
LDO Short-Circuit Current I
LDO Regulation Reduction/ Bypass Switchover Threshold
LDO Bypass Switchover Threshold
LDO Bypass Switchover Startup Timeout
LDO Bypass Switch Resistance LDO to BYP, V
VCC Undervoltage-Lockout (UVLO) Threshold
Thermal-Shutdown Threshold T
3.3V ALWAYS-ON LINEAR REGULATOR (RTC)
RTC Output-Voltage Accuracy V
RTC Short-Circuit Current I
REFERENCE (REF)
Reference Voltage V
Reference Load Regulation
REF Lockout Voltage V
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 t
PGOOD1 Output Low Voltage
PGOOD1 Leakage Current I
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
ILIM(LDO)
t
BYP
V
UVLO(VCC)
SHDN
RTC
ILIM(RTC)
REF
V
REF IREF
REF(UVLO)
V
OVP(OUT1)
t
OVP
V
UVP(OUT1)
t
UVP
PGOOD1
PGOOD1
LDO = GND 100 260 mA
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
= 5V (Note 4) 1.2 4.5
BYP
Fal ling edge of VCC, PWM disabled below this threshold
Risi ng edge of VCC 4.2
Hysteresis = 10°C +160 °C
ON1 = ON2 = GND, VIN = 6V to 24V, 0 < I
ON1 = ON2 = ONLDO = GND, V
RTC = GND 5 mA
VCC = 4.5V to 5.5V, I
Risi ng edge, 350mV (typ) hysteresis 1.95 V
With respect to error-comparator thresho ld 12 16 20 %
FB1 forced 50mV above trip threshold 10 μs
With respect to error-comparator threshold 65 70 75 %
10 μs
With respect to error-comparator threshold, falling edge, hysteresis = 1%
FB1 forced 50mV beyond PGOOD1 trip threshold, falling edge
V I
V PGOOD1 forced to 5.5V
< 5mA
RTC
= 6V to 24V, 0 < I
IN
= -20μA to +50μA -10 +10 mV
= 0.56V (PGOOD1 low impedance),
FB1
= 4mA
SINK
= 0.70V (PGOOD1 high impedance),
FB1
< 5mA
RTC
= 0 1.980 2.00 2.020 V
REF
-11.0 -8.5 -6.0 %
-6.5 %
500 μs
3.8 4.0 4.3
3.23 3.33 3.43
3.16 3.50
-20 -16 -12 %
10 μs
0.3 V
1 μA
V
V
MAX17101
Dual Quick-PWM, Step-Down Controller
with Low-Power LDO, RTC Regulator
_______________________________________________________________________________________ 5
ELECTRICAL CHARACTERISTICS (continued)
(Circuit of Figure 1, no load on LDO, RTC, OUT1, OUT2, and REF, VIN= 12V, VDD= VCC= V
SECFB
= 5V, V
REFIN2
= 1.0V, BYP =
LDOSEL = GND, ONLDO = IN, ON1 = ON2 = V
CC
, TA= 0°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C.)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
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 t
PGOOD2 Output-Low Voltage
PGOOD2 Leakage Current I
CURRENT LIMIT
ILIM_ Adjustment Range V
ILIM_ Current I
Valley Current-Limit Threshold (Adjustable)
Current-Limit Threshold (Negative)
Ultrasonic Current-Limit Threshold
Current-Limit Threshold (Zero Crossing)
V
OVP(OUT2)
t
OVP
V
UVP(OUT2)
t
OVP
t
UVP
PGOOD
PGOOD
ILIM
ILIM
V
VALLEY VAGND
V
NEG
V
NEG(US)
V
ZX
With respect to error-comparator threshold 12 16 20 %
Min imum overvoltage threshold 0.7 V
OUT2 forced 50mV above trip threshold 10 μs
With respect to error-comparator threshold 65 70 75 %
OUT2 forced 50mV above trip threshold 10 μs
OUT2 forced 50mV below trip threshold 10 μs
With respect to error-comparator threshold, falling edge, hysteresi s = 2%
OUT2 forced 50mV beyond PGOOD1 trip
_
threshold, falling edge
V
= V
OUT2
impedance), I
OUT2 = REFIN2 (PGOOD2 high impedance),
_
PGOOD2 forced to 5.5V, T
0.2 2.0 V
5 μA
- VLX_
With respect to valley current-limit threshold, SKIP = V
V
= V
OUT1
V
- VLX_, SKIP = GND or OPEN/REF 1 mV
AGND
- 150mV (PGOOD2 low
REFIN2
CC
OUT2
SINK
= V
= 4mA
= 0.77V, V
FB1
= +25°C
A
R
_ = 100k 40 50 60
ILIM
_ = 200k 87 100 113
R
ILIM
= 0.70V 25 mV
REFIN2
-20 -16 -12 %
10 μs
0.3 V
1 μA
-120 %
mV
MAX17101
Dual Quick-PWM, Step-Down Controller with Low-Power LDO, RTC Regulator
6 _______________________________________________________________________________________
ELECTRICAL CHARACTERISTICS (continued)
(Circuit of Figure 1, no load on LDO, RTC, OUT1, OUT2, and REF, VIN= 12V, VDD= VCC= V
SECFB
= 5V, V
REFIN2
= 1.0V, BYP =
LDOSEL = GND, ONLDO = IN, ON1 = ON2 = V
CC
, TA= 0°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C.)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
GATE DRIVERS
DH_ Gate Driver On-Resistance R
DL_ Gate Driver On-Resistance R
DH_ Gate Driver Source/Sink Current
DL_ Gate Driver Source Current
DL_ Gate Driver Sink Current I
Internal BST_ Switch On-Resistance
INPUTS AND OUTPUTS
TON Input Logic Level s
SKIP Input Logic Levels
SKIP, TON Leakage Current I
ON_ Input Logic Leve ls
ON_ Leakage Current I
ONLDO Input Logic Levels
ONLDO Leakage Current I
DH
DL
I
DH
I
DL
(SOURCE)
DL (SINK)
R
BST IBST
SKIP,ITON VSKIP
ON_
ONLDO VONLDO
BST1 - LX1 and BST2 - LX2 forced to 5V 1.5 3.5
DL1, DL2; high state 2.2 4.5
DL1, DL2; low state 0.6 1.5
DH1, DH2 forced to 2.5V, BST1 - LX1 and BST2 - LX2 forced to 5V
DL1, DL2 forced to 2.5V 1.7 A
DL1, DL2 forced to 2.5V 3.3 A
_ = 10mA, VDD = 5V 5
High
REF or open 1.6 3.0
Low 0.4
High (forced PWM)
Open (ultrasonic) 1.6 3.0 Low (SKIP) 0.4
= V
= 0 or 5V, TA = +25°C -2 +2 μA
TON
High (SMPS on) 2.4
Low (SMPS off) 0.8
V
= V
ON1
High (SMPS on) 2.4
Low (SMPS off) 0.8
= 0 or 5V, TA = +25°C -2 +2 μA
ON2
= 0 or 24V, TA = +25°C -1 +1 μA
2 A
V
-
CC
0.4V
V
-
CC
0.4V
V
V
V
V
MAX17101
Dual Quick-PWM, Step-Down Controller
with Low-Power LDO, RTC Regulator
_______________________________________________________________________________________ 7
ELECTRICAL CHARACTERISTICS
(Circuit of Figure 1, no load on LDO, RTC, OUT1, OUT2, and REF, VIN= 12V, VDD= VCC= V
SECFB
= 5V, V
REFIN2
= 1.0V, BYP =
LDOSEL = GND, ONLDO = IN, ON1 = ON2 = V
CC
, TA= -40°C to +85°C, unless otherwise noted.) (Note 3)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
INPUT SUPPLIES
IN Standby Supply Current I
IN Shutdown Supply Current I
IN(STBY)
IN(SHDN) VIN
IN Supply Current I
VCC Supply C urrent I
IN
CC
VIN = 6V to 24V, ON1 = ON2 = GND, ONLDO = V
CC
= 4.5V to 24V, ON1 = ON2 = ONLDO = GND 70 μA
ON1 = ON2 = REFIN2 = VCC, SKIP = FB1 = GND, V
OUT2
= 3.5V, V
OUT1
= 5.3V
ON1 = ON2 = REFIN2 = VCC, SKIP = FB1 = GND, V
OUT2
= 3.5V, V
OUT1
= 5.3V
PWM CONTROLLERS
5V preset output: FB1 = GND,
= 12V, SKIP = V
V
OUT1 Output-Voltage Accuracy (Note 1)
V
OUT1
V
FB1
IN
1.5V preset output: FB1 = VCC (5V), V
= 12V, SKIP = V
IN
Adju stab le feedback output, V
= 12V, SKIP = V
IN
CC
CC
CC
OUT1 Voltage-Adjust Range 0.7 5.5 V
FB1 Dual Mode Threshold Voltage
OUT2 Output-Voltage Accuracy (Note 1)
V
OUT2
Low 0.040 0.125
High
3.3V preset output: REFIN2 = V 12V, SKIP = V
CC
(5V), VIN =
CC
1.05V preset output: REFIN2 = RTC (3.3V), V
= 1.2V, SKIP = V
IN
Tracking output: V
= 12V, SKIP = V
V
IN
CC
REFIN2
CC
= 1.1V,
OUT2 Voltage-Adju st Range 0 2 V
REFIN2 Voltage-Adju st Range 0 2 V
REFIN2 Dual Mode Threshold Voltage
Low (REFIN2 = RTC) 2.2 3.0
High (REFIN2 = V
CC
)
TON = GND or REF
DH1 On-Time t
ON1
VIN = 12V,
= 5.0V (Note 2)
V
OUT1
(400kHz)
TON = REF or V
CC
(300kH z)
Minimum Off-Time t
SECFB Threshold Voltage V
OFF(MIN)
SECFB
(Note 2) 450 ns
1.92 2.08 V
200 μA
0.2 mA
1.5 mA
4.90 5.10
1.47 1.53
V
0.685 0.715
V
CC
1.6V
-
V
CC
0.7V
V
-
3.234 3.366
1.029 1.071
V
1.085 1.115
V
CC
1.2V
-
V
CC
0.4V
V
-
895 1209
ns
833 1017
MAX17101
Dual Quick-PWM, Step-Down Controller with Low-Power LDO, RTC Regulator
8 _______________________________________________________________________________________
ELECTRICAL CHARACTERISTICS (continued)
(Circuit of Figure 1, no load on LDO, RTC, OUT1, OUT2, and REF, VIN= 12V, VDD= VCC= V
SECFB
= 5V, V
REFIN2
= 1.0V, BYP =
LDOSEL = GND, ONLDO = IN, ON1 = ON2 = V
CC
, TA= -40°C to +85°C, unless otherwise noted.) (Note 3)
LINEAR REGULATOR (LDO)
LDO Output-Voltage Accuracy V
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
LDO
LDOSEL Dual Mode Voltage Leve l
LDO Short-Circuit Current I
LDO Regulation Reduction/ Bypass Switchover Threshold
VCC Undervoltage-Lockout Threshold
3.3V ALWAYS-ON LINEAR REGULATOR (RTC)
RTC Output-Voltage Accuracy V
RTC Short-Circuit Current I
REFERENCE (REF)
Reference Voltage V
Reference Load-Regulation Error V
OUT1 FAULT DETECTION
OUT1 Overvoltage Trip Thresho ld V
OUT1 Undervoltage-Protection Trip Threshold
PGOOD1 Lower Trip Threshold
PGOOD1 Output-Low Voltage
OUT2 FAULT DETECTION
OUT2 Overvoltage Trip Thresho ld V
ILIM(LDO)
V
UVLO(VCC)
RTC
ILIM(RTC)
REF
REF IREF
OVP(OUT1)
V
UVP(OUT1)
OVP(OUT2)
VIN = 24V, LDOSEL = BYP = GND, 0 < I
VIN = 24V, LDOSEL = VCC, BYP = GND, 0 < I
LDOSEL low 0.25
LDOSEL high
LDO = GND 260 mA
Fal ling edge of BYP -12 -5 %
Fal ling edge of VCC, PWM disabled below this threshold
ON1 = ON2 = GND, VIN = 6V to 24V, 0 < I
ON1 = ON2 = ONLDO = GND, V
RTC = GND 5 mA
VCC = 4.5V to 5.5V, I
With respect to error-comparator threshold 10 20 %
With respect to error-comparator threshold 60 80 %
With respect to error-comparator threshold, falling edge, hysteresis = 1%
V I
With respect to error-comparator threshold 10 20 %
< 100mA
LDO
< 100mA
LDO
< 5mA
RTC
= 6V to 24V, 0 < I
IN
= -20μA to +50μA -10 +10 mV
= 0.56V (PGOOD1 low impedance),
FB1
= 4mA
SINK
< 5mA
RTC
= 0 1.975 2.025 V
REF
4.85 5.15
3.20 3.40
V
-
CC
0.9V
3.8 4.3 V
3.18 3.45
3.16 3.50
-20 -10 %
0.4 V
V
V
V
MAX17101
Dual Quick-PWM, Step-Down Controller
with Low-Power LDO, RTC Regulator
_______________________________________________________________________________________ 9
ELECTRICAL CHARACTERISTICS (continued)
(Circuit of Figure 1, no load on LDO, RTC, OUT1, OUT2, and REF, VIN= 12V, VDD= VCC= V
SECFB
= 5V, V
REFIN2
= 1.0V, BYP =
LDOSEL = GND, ONLDO = IN, ON1 = ON2 = V
CC
, TA= -40°C to +85°C, unless otherwise noted.) (Note 3)
Note 1: DC output accuracy specifications refer to the threshold of the error comparator. When the inductor is in continuous conduc-
tion, the MAX17101 regulates the valley of the output ripple, so the actual DC output voltage is higher than the trip level by 50% of the output ripple voltage. In discontinuous conduction (I
OUT
< I
LOAD(SKIP)
), the output voltage has a DC regulation
level higher than the error-comparator threshold by approximately 1.5% due to slope compensation.
Note 2: On-time and off-time specifications are measured from 50% point to 50% point at the DH pin with LX = PGND, V
BST
= 5V, and a 500pF capacitor from DH to LX to simulate external MOSFET gate capacitance. Actual in-circuit times might be differ­ent due to MOSFET switching speeds.
Note 3: Specifications to T
A
= -40°C are guaranteed by design and not production tested.
Note 4:Specifications increased by 1Ω to account for test measurement error.
OUT2 Undervoltage-Protection Trip Threshold
PGOOD2 Lower Trip Threshold
PGOOD2 Output-Low Voltage
CURRENT LIMIT
ILIM_ Adjustment Range V
Valley Current-Limit Threshold (Adjustable)
GATE DRIVERS
DH_ Gate Driver On-Resistance R
DL_ Gate Driver On-Resistance R
INPUTS AND OUTPUTS
TON Input Logic Level s
SKIP Input Logic Levels
ON_ Input Logic Leve ls
ONLDO Input Logic Levels
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
V
UVP(OUT2)
ILIM
V
VALLEY VAGND
DH
DL
With respect to error-comparator threshold 60 80 %
With respect to error-comparator threshold, falling edge, hysteresis = 2%
V
= V
OUT2
impedance), I
- VLX_
BST1 - LX1 and BST2 - LX2 forced to 5V 3.5
DL1, DL2; high state 4.5
DL1, DL2; low state 1.5
High
REF or open 1.6 3.0
Low 0.4
High (forced PWM)
Open (ultrasonic) 1.6 3.0
Low (skip) 0.4
High (SMPS on) 2.4
Low (SMPS off) 0.8
High (SMPS on) 2.4
Low (SMPS off) 0.8
- 150mV (PGOOD2 low
REFIN2
SINK
= 4mA
0.2 2.0 V
R
ILIM
R
ILIM
_ = 100k 40 60
_ = 200k 85 115
-20 -10 %
0.4 V
V
-
CC
0.4V
-
V
CC
0.4V
mV
V
V
V
V
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