General Description
The MAX8513/MAX8514 integrate a voltage-mode
PWM step-down DC-DC controller and two LDO con-
trollers, a voltage monitor, and a power-on reset for the
lowest-cost power-supply and monitoring solution for
xDSL modems, routers, gateways, and set-top boxes.
The DC-DC controller switching frequency can be set
with an external resistor from 300kHz to 1.4MHz, to allow
for the optimization of cost, size, and efficiency. For noise-
sensitive applications, the DC-DC controller can also be
synchronized to an external clock, minimizing noise inter-
ference. Operation above 1.1MHz reduces noise for high
data-rate xDSL applications. An adjustable soft-start and
adjustable foldback current limit provide reliable startup
and fault protection. The DC-DC controller output voltage
can be set externally to a voltage from 1.25V to 5.5V.
Current limiting is accomplished by inductor current sens-
ing for improved efficiency, or by an external sense resis-
tor for better accuracy.
The MAX8513/MAX8514s' first LDO controller is
designed to provide a low-cost, high-current regulated
output from 0.8V to 5.5V using an N-channel MOSFET or
a low-current output using a low-cost NPN transistor. The
MAX8513's second regulator can be used to generate
0.8V to 27V output with a low-cost PNP transistor. Both
LDO regulators can operate either from the DC-DC con-
troller output or from a higher voltage derived with a fly-
back overwinding on the DC-DC converter inductor. The
MAX8514's second LDO regulator is designed to pro-
vide a negative output with an NPN transistor.
A sequence input allows the outputs to either power up
together, or for the DC-DC regulator to power up first
and each LDO controller to power up in sequence. An
input power-fail output (PFO) is provided for input
power-fail warning, such as in dying-gasp applications.
A power-on reset circuit with a 140ms delay is also
included to indicate when all outputs have achieved
regulation and stabilized.
Applications
xDSL, Cable, ISDN Modems, and Routers
Wireless Routers
Set-Top Boxes
Automotive Dashboard Electronics
Features
Low-Cost DC-DC Controller with Two LDOs
Wide Input Range: 4.5V to 28V
300kHz to 1.4MHz Adjustable Switching
Frequency
Low Noise for High Data-Rate xDSL Applications
Synchronizable to External Clock
Adjustable Soft-Start
Lossless Adjustable Foldback Current Limit
Power-On Reset with 140ms Delay
Adjustable Input Power-Fail Warning for Dying
Gasp
Selectable Output-Voltage Sequencing or
Output-Voltage Tracking
MAX8513/MAX8514
Wide-Input, High-Frequency, Triple-Output Supplies
with Voltage Monitor and Power-On Reset
________________________________________________________________ Maxim Integrated Products
1
STEP-
DOWN
CONTROLLER
V
IN
(4.5V TO 28V)
V
OUT1
(1.25V TO 5.5V)
V
OUT2
(0.8V TO V
OUT1
)
V
OUT3
(0.8V TO 27V)
LDO
CONTROLLER 1
LDO
CONTROLLER 2
OUTPUT
POWER-ON RESET
INPUT POWER-
FAIL MONITOR
MAX8513
SYNC
ON
OFF
Functional Diagram
Ordering Information
19-3178; Rev 0; 2/04
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim's website at www.maxim-ic.com.
EVALUATION KIT
AVAILABLE
PART
TEMP RANGE
PIN-PACKAGE
MAX8513
EEI
-40
°
C to +85
°
C
28 QSOP
MAX8514
EEI
-40
°
C to +85
°
C
28 QSOP
MAX8514AEI
-40
°
C to +125
°
C
28 QSOP
Pin Configurations appear at end of data sheet.
MAX8513/MAX8514
Wide-Input, High-Frequency, Triple-Output Supplies
with Voltage Monitor and Power-On Reset
2
_______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(V
IN
= V
LX
= V
SUP2
= 12V, V
PVL
= V
BST
- V
LX
= V
DRV3P
= 5V, V
SUP3N
= 3.3V, V
DRV3N
= -5V, C
VL
= 4.7µF, C
REF
= 0.22µF, R
FREQ
=
15.0k,
T
A
= 0°C to +85°C
, unless otherwise noted. Typical values are at T
A
= +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, DRV3P, SUP2 to GND.......................................-0.3V to +30V
DRV2 to GND ..........................................-0.3V to (V
SUP2
+ 0.3V)
DRV3N to GND......................(V
SUP3N
- 28V) to (V
SUP3N
+ 0.3V)
FREQ, PFI, PFO, POR, SUP3N, SYNC/EN,
CSP, CSN to GND ................................................-0.3V to +6V
VL to GND ...................-0.3V to the lesser of (V
IN
+ 0.3V) or +6V
COMP1, FB1, FB2, FB3P, FB3N, REF, ILIM,
SS, SEQ to GND......................................-0.3V to (V
VL
+ 0.3V)
PVL to PGND ............................................................-0.3V to +6V
DL to PGND...............................................-0.3V to (V
PVL
+ 0.3V)
BST to LX..................................................................-0.3V to +6V
DH to LX ....................................................-0.3V to (V
BST
+ 0.3V)
PGND to GND .......................................................-0.3V to +0.3V
VL Short Circuit to GND .............................................Continuous
Continuous Power Dissipation (T
A
= +70°C)
28-Pin QSOP (derate 10.8mW/°C above +70°C).........860mW
Operating Temperature Range
MAX8513EEI, MAX8514EEI .............................-40°C to +85°C
MAX8514AEI..................................................-40°C to +125°C
Junction Temperature ......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
GENERAL
5.5
28.0
IN Operating Range
IN = VL
4.5
5.5
V
IN Supply Current
V
FB1
= 1.3V, V
FB2
= V
FB3
= 1.0V, does not
include switching current to PVL and BST,
SYNC/EN = VL
2.6
3.2
mA
IN Shutdown Current
V
SYNC/EN
= 0, R
FREQ
= 50k
200
300
µA
VL REGULATOR
VL Output Voltage
V
IN
= 6V to 28V, I
VL
= 0.1mA to 40mA
4.75
5
5.25
V
VL Dropout Voltage
From IN to VL, V
IN
= 5V, I
VL
= 40mA
560
mV
VL Line Regulation
V
IN
= 6V to 28V, I
VL
= 5mA
0.05
%
VL Undervoltage Threshold
VL rising, V
HYST
= 675mV (typ)
3.6
4.2
V
OUT1 (BUCK CONVERTER)
Output Voltage Range
V
OUT1
(Note 1)
1.25
5.50
V
FB1 Regulation Threshold
V
FB1
1.234
1.25
1.259
V
Error-Amplifier Open-Loop
Voltage Gain
A
VOL
65
90
dB
FB1 Input Bias Current
I
FB1_BIAS
V
FB1
= 1.3V
-200
+10
+200
nA
Error-Amplifier Gain Bandwidth
25
MHz
DH Output-Resistance High
R
DH_HIGH
1.5
2.55
DH Output-Resistance Low
R
DH_LOW
1.2
2.1
DL Output-Resistance High
R
DL_HIGH
2.5
5
DL Output-Resistance Low
R
DL_LOW
0.7
1.3
Driver Dead Time
t
dt
Starts from V
DL
= 1V or (V
DH
- V
LX
) = 1V
50
ns
MAX8513/MAX8514
Wide-Input, High-Frequency, Triple-Output Supplies
with Voltage Monitor and Power-On Reset
_______________________________________________________________________________________
3
ELECTRICAL CHARACTERISTICS (continued)
(V
IN
= V
LX
= V
SUP2
= 12V, V
PVL
= V
BST
- V
LX
= V
DRV3P
= 5V, V
SUP3N
= 3.3V, V
DRV3N
= -5V, C
VL
= 4.7µF, C
REF
= 0.22µF, R
FREQ
=
15.0k,
T
A
= 0°C to +85°C
, unless otherwise noted. Typical values are at T
A
= +25°C.)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
V
ILIM
= 2.00V, V
CSN
= 0 to 5.5V
246
275
300
V
ILIM
= 0.50V, V
CSN
= 0 to 5.5V
50
67
81
Current-Limit Threshold (Positive)
V
CS
V
ILIM
= V
VL
, V
CSN
= 0 to 5.5V
151
170
188
mV
V
ILIM
= 2.00V, V
CSN
= 0 to 5.5V
-333
-272
-199
V
ILIM
= 0.50V, V
CSN
= 0 to 5.5V
-90
-67
-42
Current-Limit Threshold
(Negative)
V
CS
V
ILIM
= V
VL
, V
CSN
= 0 to 5.5V
-210
-166
-122
mV
CSP and CSN Bias Current
V
CSP
= V
CSN
= 0 to 5.5V
-120
+135
µA
ILIM Bias Current
V
ILIM
= 1.25V
-5.3
-5
-4.7
µA
SS Soft-Start Charge Current
V
SS
= 0.6V
15
25
35
µA
Soft-Start Discharge Resistance
100
200
LX, BST, PVL Leakage Current
V
LX
= V
IN
= 28V, V
BST
= 33V, V
PVL
= 5V,
V
SYNC/EN
= 0
0.03
20
µA
FB1 Power-On Reset Threshold
1.08
1.125
1.20
V
OUT2 (POSITIVE LDO)
SUP2 Operating Range
V
SUP2
(Note 1)
4.5
28.0
V
DRV2 Clamp Voltage
V
DRV2
V
FB2
= 0.75V
7.75
9.00
V
SUP2 Supply Current
160
300
µA
SUP2 Shutdown Supply Current
V
SYNC/EN
= 0
3
10
µA
FB2 Regulation Voltage
V
FB2
0.784
0.80
0.808
V
FB2 Input Bias Current
I
FB2_BIAS
V
FB2
= 0.75V
0.01
100
nA
DRV2 Output Current Limit
V
IN
= 5V, V
DRV2
= 5V, V
FB2
= 0.77V
15
30
mA
DRV2 Output Current Limit
During Soft-Start
V
IN
= 6V, V
DRV2
= 5V, V
FB2
= 0.70V
8
10
12
mA
FB2 Power-On Reset Threshold
0.690
0.720
0.742
V
FB2 to DRV2 Transconductance
G
C2
I
DRV2
= +250µA, -250µA
0.12
0.2
0.36
S
OUT3P (POSITIVE PNP LDO) (MAX8513 ONLY)
DRV3P Operating Range
V
DRV3P
1
28
V
FB3P Regulation Voltage
V
DRV3P
= 5V, I
DRV3P
= 1mA
0.790
0.803
0.816
V
FB3P to DRV3P Large-Signal
Transconductance
G
C3P
V
DRV3P
= 5V, I
DRV3P
= 0.5mA to 5mA
0.38
0.6
1.1
S
Feedback Input Bias Current
V
FB3P
= 0.75V
0.01
100
nA
DRV3P = 2.5V
15
35
Driver Sink Current
V
FB3P
= 0.75V
DRV3P = 4.0V
40
mA
FB3P POR Threshold
0.690
0.720
0.742
V
FB3P Soft-Start Period
1312
Clock
Cycles
MAX8513/MAX8514
Wide-Input, High-Frequency, Triple-Output Supplies
with Voltage Monitor and Power-On Reset
4
_______________________________________________________________________________________
ELECTRICAL CHARACTERISTICS (continued)
(V
IN
= V
LX
= V
SUP2
= 12V, V
PVL
= V
BST
- V
LX
= V
DRV3P
= 5V, V
SUP3N
= 3.3V, V
DRV3N
= -5V, C
VL
= 4.7µF, C
REF
= 0.22µF, R
FREQ
=
15.0k,
T
A
= 0°C to +85°C
, unless otherwise noted. Typical values are at T
A
= +25°C.)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
OUT3N (NEGATIVE NPN LDO CONTROLLER) (MAX8514 ONLY)
SUP3N Operating Range
(Note 1)
1.5
5.5
V
DRV3N Operating Range
(Note 1)
V
SUP3N
- 21V
V
SUP3N
- 1.5V
V
SUP3N Supply Current
V
DRV3N
= 1.5V, V
SUP3N
= 3.5V,
I
DRV3N
= -1mA (source)
1.1
2
mA
FB3N Regulation Voltage
V
DRV3N
= 1.5V, V
SUP3N
= 3.5V,
I
DRV3N
= -1mA (source)
-20
-5
+10
mV
FB3N to DRV3N Large-Signal
Transconductance
G
C3N
V
DRV3N
= 0, I
DRV3N
= -0.5mA to -5mA
(source)
0.225
0.36
0.550
S
Feedback Input Bias Current
V
FB3N
= -100mV
60
1000
nA
Driver Source Current
V
FB3N
= 200mV, V
DRV3N
= 0,
V
SUP3N
= 3.5V
13
25
mA
FB3N POR Threshold
450
500
550
mV
FB3N Soft-Start Period
2048
Clock
Cycles
REFERENCE
REF Output Voltage
V
REF
-2µA < I
REF
< +50µA
1.231
1.25
1.269
V
OSCILLATOR
R
FREQ
= 10.7k
±1% from FREQ to GND
1300
1390
1460
R
FREQ
= 15.0k
±1% from FREQ to GND
933
985
1040
Frequency
f
S
R
FREQ
= 50.0k
±1% from FREQ to GND
260
290
324
kHz
FREQ Resistance-Frequency
Product
15.0
MHz
×
k
R
FREQ
= 10.7k
±1% from FREQ to GND
77
83
91
R
FREQ
= 15.0k
±1% from FREQ to GND
80
87
95
Maximum Duty Cycle
(Measured at DH Pin)
R
FREQ
= 50.0k
±1% from FREQ to GND
93
96
99
%
Minimum On-Time
(Measured at DH Pin)
R
FREQ
= 10.7k
±1% from FREQ to GND
20
62
ns
SYNC/EN Pulse Width
Low or high (Note 1)
200
ns
SYNC/EN Frequency Range
SYNC/EN input frequency needs to be
within ±30% of the value set at the FREQ
pin (Note 1)
200
1850
kHz
SYNC/EN Input Voltage, High
2.4
V
SYNC/EN Input Voltage, Low
0.8
V
SYNC/EN Input Current
V
SYNC/EN
= 0 to 5.5V
-1
+1
µA
MAX8513/MAX8514
Wide-Input, High-Frequency, Triple-Output Supplies
with Voltage Monitor and Power-On Reset
_______________________________________________________________________________________
5
ELECTRICAL CHARACTERISTICS (continued)
(V
IN
= V
LX
= V
SUP2
= 12V, V
PVL
= V
BST
- V
LX
= V
DRV3P
= 5V, V
SUP3N
= 3.3V, V
DRV3N
= -5V, C
VL
= 4.7µF, C
REF
= 0.22µF, R
FREQ
=
15.0k,
T
A
= 0°C to +85°C
, unless otherwise noted. Typical values are at T
A
= +25°C.)
ELECTRICAL CHARACTERISTICS
(V
IN
= V
LX
= V
SUP2
= 12V, V
PVL
= V
BST
- V
LX
= V
DRV3P
= 5V, V
SUP3N
= 3.3V, V
DRV3N
= -5V, C
VL
= 4.7µF, C
REF
= 0.22µF, R
FREQ
=
15.0k,
T
A
= -40°C to +125°C
(Note 2), unless otherwise noted.)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
SEQ, PFI,
PFO
,
POR
SEQ Input-Voltage High
2.4
V
SEQ Input-Voltage Low
0.8
V
SEQ Input Current
V
SEQ
= 0 to V
VL
1
10
µA
I
POR
= 1.6mA
10
200
POR Output-Voltage Low
V
FB1
, V
FB2
, V
FB3P
,
V
FB3N
, out-of-regulation
I
POR
= 0.1mA,
V
IN
= 1.0V
20
200
mV
POR Output Leakage Current
V
FB1
, V
FB2
, and V
FB3P
or V
FB3N
, in-
regulation
0.001
1
µA
POR Power-Ready Delay Time
From V
FB1
, V
FB2
, and V
FB3P
or V
FB3N
, in-
regulation to POR = high impedance
140
315
560
ms
PFI Input Threshold
Falling, V
HYST
= 20mV
1.20
1.22
1.25
V
PFI Input Bias Current
V
PFI
= 1.0V
0.1
100
nA
I
PFO
= 1.6mA
20
200
PFO Output-Voltage Low
PFI = 1.1V
I
PFO
= 0.1mA,
V
IN
= 1.0V
10
200
mV
PFO Output Leakage Current
PFI = 1.4V, PFO = 5V
0.001
1
µA
THERMAL PROTECTION
Thermal Shutdown
Junction temperature rising
+170
°C
Thermal-Shutdown Hysteresis
25
°C
PARAMETER
SYMBOL
CONDITIONS
MIN
MAX
UNITS
GENERAL
5.5
28.0
IN Operating Range
IN = VL
4.5
5.5
V
IN Supply Current
V
FB1
= 1.3V, V
FB2
= V
FB3
= 1.0V, does not
include switching current to PVL and BST,
SYNC/EN = VL
3.2
mA
IN Shutdown Current
V
SYNC/EN
= 0, R
FREQ
= 50k
300
µA
VL REGULATOR
VL Output Voltage
V
IN
= 6V to 28V, I
VL
= 0.1mA to 40mA
4.75
5.25
V
VL Dropout Voltage
From IN to VL, V
IN
= 5V, I
VL
= 40mA
610
mV
VL Undervoltage Threshold
VL rising, V
HYST
= 675mV (typ)
3.6
4.2
V
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