Small 2A, Low-Dropout Linear Regulator in a 2.7mm x 1.6mm

Small 2A, Low-Dropout Linear Regulator in a 2.7mm x 1.6mm
EVALUATION KIT AVAILABLE
MAX15102
Small 2A, Low-Dropout Linear Regulator
in a 2.7mm x 1.6mm Package
General Description
The MAX15102 is a small, low-dropout linear regulator
optimized for networking, datacom, and server applications. The regulator delivers up to 2A from a 1.7V to 5.5V
input supply with output accuracy of Q1.6%. The output
is adjustable down to 0.6V with a guaranteed dropout
voltage of less than 150mV at full load. The internal
p-channel switch is protected with a foldback current limit
and thermal shutdown.
The MAX15102 features an external bypass input to
reduce noise. This bypass input also serves as a softstart control. An enable input and power-good output are
included for power sequence control.
The MAX15102 is available in a 1.6mm x 2.7mm WLP
package and is fully specified from the -40NC to +105NC
operating temperature range.
Benefits and Features
●● High-Accuracy LDO Provides Stable Power to
Sensitive Processors
• ±1.6% Output Accuracy Over Line, Load, and
Temperature
• Low Noise 15µVRMS (typ)
• 150mV Dropout Guaranteed at 2A
●● Small Solution Size Allows More Space for Digital
Circuitry
• 1.6mm x 2.7mm WLP Package
• Integrated Thermal-Shutdown Protection
• Integrated Foldback Current Protection
●● Wide Voltage Ranges Accommodate Low-Voltage
POL Requirements
• Adjustable Output from 0.6V to 5.2V
• 1.7V to 5.5V Operating Range
Applications
●●
●●
●●
●●
●●
Networking
Telecom/Datacom
Servers
Base Stations
PLL Power
Ordering Information appears at end of data sheet.
Typical Operating Circuit
INPUT
(1.7V TO 5.5V)
OUTPUT
(0.6V TO VIN - 200mV)
OUT
IN
MAX15102
CIN
2.2µF
R1
0 TO 4.6kI
EN
PG
FB
POWER-GOOD
OUTPUT
GND
SS_BYP
CSS
100nF
19-6155; Rev 3; 1/17
R2
600I
COUT
22µF
MAX15102
Small 2A, Low-Dropout Linear Regulator
in a 2.7mm x 1.6mm Package
Absolute Maximum Ratings
IN, SS_BYP, FB to GND ..........................................-0.3V to +6V
EN, PG, OUT to GND..................................-0.3V to (VIN + 0.3V)
OUT Short Circuit.......................................................Continuous
Continuous Power Dissipation (TA = +70NC)
WLP (derate 19.2mW/NC above +70NC).....................1538mW
Operating Temperature Range ....................... -40NC to +105NC
Storage Temperature Range .......................... -65NC to +150NC
Junction Temperature .....................................................+150NC
Soldering Temperature (reflow) (Note 1).........................+260NC
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.
Note 1: The WLP package is constructed using a unique set of package techniques that impose a limit on the thermal profile. The
device can be exposed during board-level solder attach and rework. This limit permits only the use of the solder profiles
recommended in the industry-standard specification JEDEC 020A, paragraph 7.6, Table 3 for IR/VPR and convection
reflow. Preheating is required. Hand or wave soldering is not allowed.
Package Information
15 WLP
Package Code
W151B2+1
Outline Number
21-0205
Land Pattern Number
Refer to Application Note 1891
THERMAL RESISTANCE, FOUR-LAYER BOARD
Junction to Ambient (θJA)
+30°C/W
Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-layer board.
For detailed information on package thermal considerations, refer to www.maximintegrated.com/thermal-tutorial.
For the latest package outline information and land patterns (footprints), go to www.maximintegrated.com/packages. Note that a “+”, “#”,
or “-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains
to the package regardless of RoHS status.
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Maxim Integrated │ 2
MAX15102
Small 2A, Low-Dropout Linear Regulator
in a 2.7mm x 1.6mm Package
Electrical Characteristics
(VIN = 3.3V, VOUT = 1.5V, VEN = VIN, IOUT = 100mA, CIN = 2.2µF, COUT = 22µF, TA = TJ = -40NC to +105NC, typical values are at
TA = +25NC, unless otherwise noted.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
5.5
V
1.624
1.69
V
IN
Input Voltage Range
VIN
Input Undervoltage Lockout
VIN_UV
Input Undervoltage Lockout
Hysteresis
VIN_UV_HYS
1.7
VIN rising
40
mV
OUT
Output Voltage Range
VOUT
0.6
5.2
0.1
V
Load Regulation
IOUT = 30mA to 2A
Line Regulation
VIN = 1.7V to 5.5V, VOUT = 0.6V,
IOUT = 190mA
Dropout Voltage
IOUT = 2A, VFB = 580mV (Note 3)
50
In-Regulation Current Limit
VIN = 5.5V, VFB = 500mV
2.5
A
Short-Circuit Foldback Current
Limit
VIN = 5.5V, VOUT = 0V, VFB < 100mV
1.4
A
Output Shutdown Leakage
VIN = 5.5V, VOUT = 0V,
VEN = 0V
-0.15
%/A
+0.15
%/V
150
mV
-40°C to
+85°C
4
-40°C to
+105°C
4.6
FA
Line Transient
DVIN = 0.5V, tRISE = tFALL = 5Fs
2
%
Load Transient
IOUT = 100mA to 1A to 100mA,
tRISE = tFALL = 1Fs
1.3
%
Power-Supply Rejection
Frequency = 100kHz, IOUT = 500mA
40
dB
Output Voltage Noise
Frequency = 500Hz to 100kHz,
IOUT = 100mA
15
FVRMS
FB
FB Threshold Accuracy
FB Input Current
IOUT = 190mA, VOUT = 1.5V to 5V,
VIN = (VOUT + 0.3V) to 5.5V
593
IOUT = 3mA to 2A, VOUT = 1.5V to 5V,
VIN = (VOUT + 0.3V) to 5.5V
590
600
606
mV
610
VFB = 0.6V, VIN = 5.5V
1
FA
3.5
mA
1
FA
GND
Ground Supply Current
Ground Shutdown Current
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1.8
VIN = 1.7V to 5.5V
Maxim Integrated │ 3
MAX15102
Small 2A, Low-Dropout Linear Regulator
in a 2.7mm x 1.6mm Package
Electrical Characteristics (continued)
(VIN = 3.3V, VOUT = 1.5V, VEN = VIN, IOUT = 100mA, CIN = 2.2µF, COUT = 22µF, TA = TJ = -40NC to +105NC, typical values are at
TA = +25NC, unless otherwise noted.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
FB = high
638
650
662
FB = low
538
550
562
25
80
UNITS
POWER-GOOD OUTPUT
Power-Good (PG) Threshold
VFB moving out of
regulation, VHYS = 15mV
Power-Good (PG) OutputVoltage Low
IPG = 2mA (sink)
Power-Good (PG) Delay
100
Power-Good (PG) Leakage
VPG = 5.5V
mV
mV
Fs
1
FA
ENABLE
Enable Input High Threshold
VEN_HIGH
Enable Input Low Threshold
VEN_LOW
Enable Input Bias Current
1.2
VEN = 0 to 5.5V
V
0.4
V
+1
FA
9.2
12
FA
45
100
I
-1
SOFT-START
Soft-Start Charging Current
VSS_BYP = 100mV
Soft-Start Pulldown Resistance
VEN = 0V, ISS_BYP = 2mA
8
THERMAL SHUTDOWN
Thermal Shutdown Threshold
Thermal Shutdown Hysteresis
Threshold falling
+160
NC
15
NC
Note 2: All devices 100% production tested at TA = +25°C. Limits over the temperature range are guaranteed by design.
Note 3: Dropout is defined as VIN - VOUT when VOUT falls 3% below its nominal voltage value.
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Maxim Integrated │ 4
MAX15102
Small 2A, Low-Dropout Linear Regulator
in a 2.7mm x 1.6mm Package
Typical Operating Characteristics
(VIN = 1.8V, VOUT = 1.5V, TA = +25NC, unless otherwise noted.)
DROPOUT VOLTAGE
vs. OUTPUT CURRENT
toc01
0.10
70
OUTPUT VOLTAGE ERROR (%)
DEFINED VIN - VOUT WHEN VOUT
FALLS 2% BELOW NOMINAL
60
50
40
VOUT = 2.5V
30
VOUT = 1.8V
20
VOUT = 3.3V
10
0
0.5
1.0
1.515
VOUT = 3V
0
VOUT = 1.5V V
OUT = 2.5V
-0.05
2.0
0
0.5
1.0
1.5
2.0
2.5
OUTPUT CURRENT (A)
OUTPUT CURRENT (A)
OUTPUT VOLTAGE
vs. TEMPERATURE
STARTUP WAVEFORMS
toc04
1.505
1.500
1.495
1.485
3.0
1.8
1V/div
IIN
1.492
2A/div
1.490
VOUT
1.488
1V/div
1A LOAD 2A LOAD
1.486
VPG
1.484
1V/div
1.482
1.480
-40
-15
10
35
60
4.8
5.3
toc06
8
7
6
5
4
3
2
1
25
5
45
65
85
100
CAPACITOR VALUE (nF)
TEMPERATURE (°C)
FB VOLTAGE vs. TEMPERATURE
(VOUT = 1.5V)
0.600
0.599
1A LOAD-TRANSIENT RESPONSE
toc07
toc08
NO LOAD
0.598
FB VOLTAGE (V)
4.3
0
1ms/div
85
3.8
9
SOFT-START TIME (ms)
NO LOAD
3.3
10
VEN
1.494
2.8
SOFT-START TIME
vs. CAPACITOR VALUE
toc05
1.498
2.3
INPUT VOLTAGE (V)
CSS =100nF
1.496
toc03
IOUT = 0.5A
1.510
0.05
-0.10
1.5
1.500
OUTPUT VOLTAGE (V)
toc02
1.490
VOUT = 5V
0
OUTPUT VOLTAGE
vs. INPUT VOLTAGE
OUTPUT VOLTAGE (V)
80
DROPOUT VOLTAGE (mV)
OUTPUT VOLTAGE ERROR
vs. OUTPUT CURRENT
VOUT
AC-COUPLED
50mV/div
1A LOAD
0.597
0.596
0.595
2A LOAD
1A
0.594
IOUT
500mA/div
0.593
100mA
0.592
0.591
-40
-15
10
35
60
85
40µs/div
TEMPERATURE (°C)
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Maxim Integrated │ 5
MAX15102
Small 2A, Low-Dropout Linear Regulator
in a 2.7mm x 1.6mm Package
Typical Operating Characteristics (continued)
(VIN = 1.8V, VOUT = 1.5V, TA = +25NC, unless otherwise noted.)
2A LOAD-TRANSIENT RESPONSE
LINE-TRANSIENT RESPONSE
toc10
toc09
ILOAD = 1A
2.3V
VOUT
AC-COUPLED
50mV/div
VIN
200mV/div
1.8V
2A
VOUT
AC-COUPLED
20mV/div
IOUT
1A/div
100mA
100µs/div
40µs/div
GROUND CURRENT
vs. INPUT VOLTAGE
FOLDBACK CURRENT-LIMIT WAVEFORMS
toc11
3.0
IOUT
2A/div
2.5
GROUND CURRENT (mA)
VOUT
500mV/div
toc12
2.0
ILOAD = 1A
1.5
1.0
ILOAD = 0A
0.5
0
100µs/div
0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5
INPUT VOLTAGE (V)
PSRR vs. FREQUENCY
(ILOAD = 0.5A)
SHORT-CIRCUIT WAVEFORMS
toc13
VIN
2V/div
90
VOUT
1V/div
70
VPG
2V/div
200µs/div
60
50
40
30
CSS = 4.7nF
12
9
CSS = 100nF
6
20
10
10Hz
100kHz
FREQUENCY (Hz)
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toc15
NO CSS
15
NOISE DENSITY (µVRMS)
IOUT
5A/div
18
80
PSRR (dB)
1.8V
NOISE DENSITY
(ILOAD = 100mA)
toc14
1MHz
3
100
1k
10k
100k
FREQUENCY (Hz)
Maxim Integrated │ 6
MAX15102
Small 2A, Low-Dropout Linear Regulator
in a 2.7mm x 1.6mm Package
Bump Configuration
TOP VIEW
MAX15102
1
2
3
4
5
EN
PG
GND
SS_BYP
FB
IN
IN
IN
IN
IN
OUT
OUT
OUT
OUT
OUT
+
A
B
C
WLP
Bump Description
BUMP
NAME
FUNCTION
A1
EN
Active-High Enable Input. Drive EN logic-high to enable the LDO. Connect to IN for always-on
operation.
A2
PG
Power-Good Output. Open-drain output asserts high when the voltage is within regulation.
A3
GND
A4
SS_BYP
A5
FB
Feedback Input. Connect a resistive divider from OUT to GND to set the output voltage.
B1, B2, B3,
B4, B5
IN
Supply Voltage Input. Connect to supply voltage from 1.7V to 5.5V. Bypass IN to GND with a 2.2FF
or greater ceramic capacitor.
C1, C2, C3,
C4, C5
OUT
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Ground
SS_BYP Bypass/Soft-Start Input. Connect a ceramic capacitor from SS_BYP to GND to reduce the
output noise and set the soft-start ramp time.
Regulated Output. Connect a 22FF capacitor from OUT to GND. For better load transient
performance a larger capacitor can be used.
Maxim Integrated │ 7
MAX15102
Small 2A, Low-Dropout Linear Regulator
in a 2.7mm x 1.6mm Package
Functional Diagram
SS_BYP
IN
UNDERVOLTAGE
LOCKOUT
THERMALOVERLOAD
PROTECTION
0.60V
REF
EN
0.55V
gM
ERROR
AMPLIFIER
P
0.65V
SHUTDOWN
LOGIC
ILIM
OUT
FB
GND
PG
MAX15102
PG
CIRCUITRY
Detailed Description
The MAX15102 is a small, low-dropout linear regulator
optimized for server, network, and telecom applications.
The regulator delivers up to 3A from a 1.7V to 5.5V
input supply with output accuracy of Q1.6%. The output
is adjustable down to 0.6V with a guaranteed dropout
voltage of less than 150mV at full load. The internal
p-channel switch is protected with a foldback current limit
and thermal shutdown.
The MAX15102 features an external bypass input to
reduce noise. This bypass input also serves as a softstart control. An enable input and power-good output are
included for power sequence control.
Internal p-Channel Pass Transistor
The MAX15102 features a 2A p-channel MOSFET pass
transistor. Unlike similar designs with pnp pass transistors,
the gate-drive current to the p-channel power transistor is
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N
extremely low. PNP-based regulators also waste considerable current in dropout when the pass transistor saturates
and uses high base-drive currents under large loads. The
MAX15102 does not suffer from these deficiencies and
consumes only 1.8mA of quiescent current even in dropout.
Output Voltage Selection
The MAX15102 features an adjustable output. The output
voltage can be set between +0.6V to VIN - 200mV using
an external resistive voltage-divider to FB (see the Typical
Operating Circuit). The output voltage is set using the following equation:
VOUT = VFB (1 + R1/R2)
where VFB = +600mV.
To simplify resistor selection:
R1 = R2 (VOUT/VFB - 1)
Set R2 to 600I.
Maxim Integrated │ 8
MAX15102
Enable
A logic-low on EN disables the MAX15102. In shutdown,
the pass transistor, control circuitry, reference, and all
biases are turned off, reducing supply current to typically
1FA. Connect EN to IN for normal operation. In shutdown,
the soft-start capacitor is discharged using an internal
pulldown resistance.
Soft-Start
As shown in the Typical Operating Circuit, the MAX15102
uses a gM stage and integrating capacitor CSS to control
the regulator’s feedback set point. When EN is driven low,
the soft-start capacitor is discharged. When EN is driven
high or power is applied to the device, a constant 9.2FA
current charges the soft-start capacitor. At startup, the
feedback set point increases linearly, which reduces the
inrush supply current.
tSS = 6.315 x 10-5 x CSS
where CSS is in nF. Use capacitor values between 30nF
to 100nF with voltage ratings greater than 5V.
Because this ramp is applied to the current-limit comparator, the actual time for the output voltage to ramp up
depends on the load current and output capacitor. Leave
SS_BYP unconnected to disable soft-start.
Foldback Current Limiting
The MAX15102 features a 2.5A current limit when the
output voltage is in regulation. When the voltage at the
output drops to 17% of its nominal value, the current
limit exponentially folds back to 1.4A. The output can be
shorted to ground for an indefinite period of time without
damaging the device. Avoid continuous output current of
greater than 2A to prevent damage to the regulator.
Small 2A, Low-Dropout Linear Regulator
in a 2.7mm x 1.6mm Package
Operating Region and Power Dissipation
The power dissipation across the device is P = IOUT
(VIN - VOUT). The resulting maximum power dissipation is:
PMAX = [(TJ(MAX) - TA)/(BJA)]
where (TJ(MAX) - TA) is the temperature difference
between the maximum allowed die junction (+150NC) and
the surrounding air. Figure 1 shows the allowable power
dissipation for typical PCBs at +25NC, +50NC, and +70NC
ambient temperatures (refer to the MAX15102 EV kit).
Applications Information
Capacitor Selection and Regulator Stability
Capacitors are required at the MAX15102’s input and output. Connect at least a 2.2FF capacitor between IN and
GND (CIN) and a 22FF capacitor between OUT and GND
(COUT). 10µF can be used for lower current operation (1A
for example). Use only surface-mount ceramic capacitors
that have low equivalent series resistance (ESR). Make
the input and output traces at least 2.5mm wide, and connect CIN and COUT within 6mm of the IC to minimize the
impact of PCB trace inductance.
The output capacitor’s ESR can affect stability and output
noise. Use capacitors with 50mI or less ESR to ensure
stability and optimum transient response. This is particularly true in applications with very low output voltage
(< 2V) and high output current (> 0.5A).
Since some capacitor dielectrics can vary over bias voltage and temperature, consult the capacitor manufacturer
specifications to ensure that the capacitors meet these
requirements over all combinations of operating voltage
and temperature.
Thermal-Overload Protection
Thermal-overload protection is designed to safeguard the
MAX15102 in the event of fault conditions. For continuous
operation, do not exceed the junction temperature rating
of TJ = +125NC.
2.5
MAXIMUM OUTPUT CURRENT (A)
A thermal-overload circuit limits total power dissipation in
the MAX15102. When the junction temperature exceeds
TJ = +160NC, the thermal sensor turns off the pass transistor, allowing the IC to cool. The thermal sensor turns the
pass transistor on once the IC’s junction temperature drops
approximately 15NC. Continuous short-circuit conditions
consequently result in a foldback limited output.
2.0
TA = +25NC
1.5
1.0
TA = +50NC
0.5
TA = +70NC
TJ = +125NC (BASED ON MAX15102 EV KIT)
0
0
1
2
3
4
5
INPUT-OUTPUT DIFFERENTIAL VOLTAGE (V)
Figure 1. Maximum Output Current Curves
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Maxim Integrated │ 9
MAX15102
Input-Output (Dropout) Voltage
A regulator’s minimum input-to-output voltage differential
(dropout voltage) determines the lowest usable supply
voltage. The dropout voltage is simply the product of
regulator’s RDS(ON) for the pass device and rated load
current. The MAX15102‘s RDS(ON) is 25mI, at 2A this
yields a dropout voltage of 50mV (see the Electrical
Characteristics and the Dropout Voltage vs. Output
Current graph in the Typical Operating Characteristics).
Noise, PSRR, and Transient Response
Small 2A, Low-Dropout Linear Regulator
in a 2.7mm x 1.6mm Package
Ordering Information
PART
MAX15102EWL+
TEMP RANGE
PIN-PACKAGE
-40NC to +105NC
15 WLP
+Denotes a lead(Pb)-free/RoHS-compliant package.
Chip Information
PROCESS: BiCMOS
The MAX15102 is designed to achieve low dropout voltage while still maintaining good noise, transient response,
and AC rejection. When operating from very noisy sources, supply noise rejection and transient response can
be improved by increasing the values of the input and
output capacitors. The MAX15102 output noise is typically
15FVRMS (see the Noise Density graph in the Typical
Operating Characteristics).
Thermal Considerations
in PCB Layout
The rated package dissipation strongly depends on the
copper area connected to the regulator. The maximum
power dissipation allowed in the package is 1538mW
(measured from the MAX15102 EV kit).
More power dissipation can be handled by the package if
great attention is given during PCB layout. For example,
using the top and bottom copper as a heatsink and
connecting the thermal vias to one of the middle layers
(GND) transfers the heat from the package into the board
more efficiently, resulting in lower junction temperature at
high power dissipation in some MAX15102 applications.
Furthermore, the solder mask around the IC area on both
top and bottom layers can be removed to radiate the heat
directly into the air. The maximum allowable power dissipation in the IC is as follows:
PMAX = [(TJ(MAX) - TA)/(BJA)]
where (TJ(MAX) - TA) is the temperature difference
between the maximum-allowed die junction (+150NC) and
the surrounding air.
A sample layout is available on the MAX15102 EV kit.
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Maxim Integrated │ 10
MAX15102
Small 2A, Low-Dropout Linear Regulator
in a 2.7mm x 1.6mm Package
Revision History
REVISION
NUMBER
REVISION
DATE
0
12/11
Initial release
—
1
4/15
Updated Benefits and Features section
1
2
8/16
Updated Absolute Maximum Ratings section
2
1/17
Updated operating temperature range in General Description and Absolute
Maximum Ratings sections; Electrical Characteristics and Ordering
Information table.
3
PAGES
CHANGED
DESCRIPTION
1–3, 10
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim Integrated’s website at www.maximintegrated.com.
Maxim Integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim Integrated product. No circuit patent licenses
are implied. Maxim Integrated reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits)
shown in the Electrical Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance.
Maxim Integrated and the Maxim Integrated logo are trademarks of Maxim Integrated Products, Inc.
© 2017 Maxim Integrated Products, Inc. │ 11
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