MAX8544EEP+ Fast Delivery |IC PHOENIX CO.,LIMITED

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MAX8546EUB ,Low-Cost / Wide Input Range / Step-Down Controllers with Foldback Current LimitTable of Contents I. ........Device Description V. ........Quality Assurance Information II ..
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MAX8544EEP+
Step-Down Controllers with Prebias Startup, Lossless Sensing, Synchronization, and OVP
General Description
The MAX8543/MAX8544 current-mode, constant-fre-
quency PWM buck controllers operate from a 3V to
13.2V input supply and generate adjustable 0.8V to 0.9
x VINoutput voltages at loads up to 25A. They feature
adjustable switching frequency and synchronization for
noise-sensitive applications.
The MAX8543/MAX8544 can start with (or without) a pre-
existing bias on the output, without discharging the out-
put. This feature simplifies tracking supply designs for
core and I/O applications and redundant supply designs.
The MAX8543/MAX8544 use the DC resistance of the
output inductor as the current-sense element for loss-
less, low-cost current sensing. The current-sense
threshold can be set to four discrete levels to accom-
modate inductors with different DC resistance values.
The MAX8544 features a power-OK monitor and two
MAX8544 controllers that can operate at 180°out-of-
phase for dual-output applications.
Applications
Base Stations
Networks and Telecom
Storage
Servers
FeaturesPrebias Startup/Monotonic1% Output AccuracyCeramic, Polymer, or Electrolytic Capacitors200kHz to 1MHz Adjustable Frequency160kHz to 1.2MHz SynchronizationLossless, Foldback Current LimitOvervoltage ProtectionEnable (On/Off)Adjustable Soft-StartMAX8544
Latch-Off/Autorecovery
Power-OK Monitor
Out-of-Phase Clock Output
MAX8543/MAX8544
Step-Down Controllers with Prebias Startup,
Lossless Sensing, Synchronization, and OVP
Ordering Information
MAX8543
OPTIONAL
SYNCHRONIZATION
OFF
BST
VIN = 3V
TO 5.5V
COMP
ILIM
FSYNC
PGND
GND
CS+
CS-
INPUT 3V TO 13.2V
OUTPUT
0.8V TO 0.9 x VIN
UP TO 25A
POK (MAX8544)ypical Operating Circuit
19-3155; Rev 0; 5/04PART TEMP RANGE PIN-PACKAGE
MAX8543EEE-40°C to +85°C16 QSOP
MAX8544EEP-40°C to +85°C20 QSOP
Pin Configurations appear at end of data sheet.
MAX8543/MAX8544
Step-Down Controllers with Prebias Startup,
Lossless Sensing, Synchronization, and OVP
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(VIN= 13.2V, VBST- VLX= 5V, 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, EN, CS+, CS- to GND.......................................-0.3V to +14V
BST, DH to LX ..........................................................-0.3V to +6V
BST to GND............................................................-0.3V to +20V
DL, COMP, ILIM2, SS, SYNCO,
FSYNC to GND .......................................-0.3V to (VVL+ 0.3V)
VL, FB, POK, ILIM1, ILIM, MODE to GND................-0.3V to +6V
PGND to GND.......................................................-0.3V to +0.3V
Continuous Power Dissipation (TA= +70°C)
16-Pin QSOP (derate 8.3mW/°C above +70°C) .......666.7mW
20-Pin QSOP (derate 9.1mW/°C above +70°C) .......727.3mW
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°CPARAMETER CONDITIONS MIN TYP MAX UNITSOperating Input Voltage Range VL connected to IN for VIN < 5.5V 3.0 13.2 VQuiescent Supply Current VFB = 0.9V, no switching 2 3 mAEN = GND, MODE = GND, IN not connected to VL 10 Shutdown Supply Current EN = GND, VL = IN, MODE = GND 20 µAVL Undervoltage-Lockout Trip Level VVL rising, typical hysteresis is 80mV 2.52 2.7 2.88 VOutput Voltage Adjust Range (VOUT) (Note 1) 0.8 VVL Output Voltage 5.5V < VIN < 13.2V, 1mA < IVL < 75mA 4.5 5 5.5 VVL Output Current 75 mAVOLTAGE REFERENCESS Shutdown Resistance From SS to GND, VEN = 0V 20 100 ΩSS Soft-Start Current VREF = 0.625V 14 24 34 µASoft-Start Ramp Time Output from 0% to 100%, CREF = 0.01µF to 1µF 33 ms/µFERROR AMPLIFIERFB Regulation Voltage 0.792 0.8 0.808 VTransconductance 70 110 160 µSCOMP Shutdown Resistance From COMP to GND, VEN = 0V 20 100 ΩFB Input Leakage Current VFB = 0.9V 5 100 nAFB Input Common-Mode Range -0.1 +0.9 VCURRENT-SENSE AMPLIFIER
VILIM1 = 0V8.81113.2
VILIM1 = (1/3)VVL4.867.2
VILIM1 = (2/3)VVL3.244.8 Voltage GainVOUT = 0 to 13V
VILIM1 = VVL2.433.6
V / V CURRENT LIMITILIM2 Output Current (MAX8544 Only) RILIM2 = 50kΩ to 200kΩ 4.5 5 5.5 µAILIM1 Input Current VILIM1 = 0V or VVL -1 +1 µA
MAX8543/MAX8544
Step-Down Controllers with Prebias Startup,
Lossless Sensing, Synchronization, and OVP
ELECTRICAL CHARACTERISTICS (continued)
(VIN= 13.2V, VBST- VLX= 5V, TA= 0°C to +85°C,unless otherwise noted. Typical values are at TA= +25°C.)PARAMETER CONDITIONS MIN TYP MAX UNITSVCS+ - VCS-, VILIM1 = 0V 38.5 50 56.5VCS+ - VCS-, VILIM1 = (1/3)VVL 85 100 115VCS+ - VCS-, VILIM1 = (2/3)VVL 127.5 150 172.5VCS+ - VCS-, VILIM1 = VVL 170 200 230VLX - VPGND, RILIM2 = 50kΩ (MAX8544 only) -42.5 -50 -57.5VLX - VPGND, RILIM2 = 200kΩ (MAX8544 only) -160 -200 -240VLX - VPGND, VFB = 0.8V (MAX8543 only) -110 -130 -150Current-Limit ThresholdVLX - VPGND, VFB = 0V (MAX8543 only) -20 -30 -40mVNegative Current-Limit Threshold % of positive-direction current limit VLX - VPGND -25 -50 -85 %CS+, CS- Input Current VCS+ = VCS- = 0 or 5V -40 +40 µACS+, CS- Input Common-Mode Range 0 13.2 VOSCILLATORRFSYNC = 18.2kΩ 800 1000 1200 Switching Frequency RFSYNC = 158kΩ 200 kHzMinimum Off-Time Measured at DH 150 220 270 nsMinimum On-Time Measured at DH 90 145 nsFSYNC Synchronization Range 160 1200 kHzFSYNC Input High Pulse Width 100 nsFSYNC Input Low Pulse Width 100 nsFSYNC Rise/Fall Time 100 nsSYNCO Phase Shift from DH Rising RFSYNC = 18.2kΩ, free-running mode,
at maximum duty cycle 165 180 195 DegreesSYNCO Output Low Level ISYNCO = 5mA 0.4 VSYNCO Output High Level ISYNCO = 5mA VVL - 1V VMOSFET DRIVERS(VBST - VLX) = 5V 1 2.5 DH On-Resistance, High State (VBST - VLX) = 3V 1.2 Ω(VBST - VLX) = 5V 1 2.5 DH On-Resistance, Low State (VBST - VLX) = 3V 1.2 ΩVVL = 5V 1 2.5 DL On-Resistance, High State VVL = 3V 1.2 ΩVVL = 5V 0.6 1.7 DL On-Resistance, Low State VVL = 3V 0.8 ΩLow-side off to high-side on 55 Break-Before-Make Dead Time High-side off to low-side on 40 nsLX, BST, IN Leakage Current VBST = 18.7V, VLX = 13.2V, VIN = 13.2V 5 µATHERMAL PROTECTIONThermal Shutdown Rising temperature +160 °CThermal-Shutdown Hysteresis 15 °C
MAX8543/MAX8544
Step-Down Controllers with Prebias Startup,
Lossless Sensing, Synchronization, and OVP
ELECTRICAL CHARACTERISTICS (continued)
(VIN= 13.2V, VBST- VLX= 5V, TA= 0°C to +85°C,unless otherwise noted. Typical values are at TA= +25°C.)PARAMETER CONDITIONS MIN TYP MAX UNITSPOKPower-OK Threshold VFB rising, percent of VOUT,
typical hysteresis is 3% 88 91 94 %POK Output Voltage, Low VFB = 0.6V, IPOK = 2mA 25 200 mVPOK Leakage Current, High VPOK = 5.5V 0.001 1 µAOVERVOLTAGE PROTECTION (OVP)Output Overvoltage Fault-Trip level Rising edge compared to regulation set point;
triggers after one or two clock cycles +110 +115 +120 %MODE CONTROLMODE Logic-Level Low 3V ≤ VVL ≤ 5.5V 0.4 VMODE Logic-Level High 3V ≤ VVL ≤ 5.5V 1.8 VVMODE = 0V -1 +1 MODE Input Current MODE = VL 5 10 µASHUTDOWN CONTROLEN Logic-Level Low 3V ≤ VVL ≤ 5.5V 0.45 VEN Logic-Level High 3V ≤ VVL ≤ 5.5V 2 VVEN = 0 or 5.5V -1 +4 EN Input Current VEN = 13.2V 1.5 6 µA
ELECTRICAL CHARACTERISTICS
(VIN= 13.2V, VBST- VLX= 5V, TA= -40°C to +85°C,unless otherwise noted.) (Note 2)PARAMETER CONDITIONS MIN MAX UNITSOperating Input Voltage Range VL connected to IN for VIN < 5.5V 3.0 13.2 VQuiescent Supply Current VFB = 0.9V, no switching 3 mAEN = GND, MODE = GND, IN not connected to VL 10 Shutdown Supply Current EN = GND, VL = IN, MODE = GND 20 µAVL Undervoltage-Lockout Trip Level VVL rising, typical hysteresis is 80mV 2.52 2.88 VOutput Voltage Adjust Range (VOUT) (Note 1) 0.8 VVL Output Voltage 5.5V < VIN < 13.2V, 1mA < IVL < 75mA 4.5 5.5 VVL Output Current 75 mAVOLTAGE REFERENCESS Shutdown Resistance From SS to GND, VEN = 0V 100 ΩSS Soft-Start Current VREF = 0.625V 14 34 µAERROR AMPLIFIERFB Regulation Voltage 0.788 0.808 VTransconductance 70 160 µSCOMP Shutdown Resistance From COMP to GND, VEN = 0V 100 ΩFB Input Leakage Current VFB = 0.9V 100 nAFB Input Common-Mode Range -0.1 +0.9 V
MAX8543/MAX8544
Step-Down Controllers with Prebias Startup,
Lossless Sensing, Synchronization, and OVP
ELECTRICAL CHARACTERISTICS (continued)
(VIN= 13.2V, VBST- VLX= 5V, TA= -40°C to +85°C,unless otherwise noted.) (Note 2)PARAMETER CONDITIONS MIN MAX UNITSCURRENT-SENSE AMPLIFIER
VILIM1 = 0V8.813.2
VILIM1 = (1/3)VVL4.87.2
VILIM1 = (2/3)VVL3.24.8 Voltage GainVOUT = 0 to 13V
VILIM1 = VVL2.43.6
V / V CURRENT LIMITILIM2 Output Current (MAX8544 Only) RILIM2 = 50kΩ to 200kΩ 4.2 5.5 µAILIM1 Input Current VILIM1 = 0V or VVL -1 +1 µAVCS+ - VCS-, VILIM1 = 0V 38.5 56.5VCS+ - VCS-, VILIM1 = (1/3)VVL 85 115VCS+ - VCS-, VILIM1 = (2/3)VVL 127.5 172.5VCS+ - VCS-, VILIM1 = VVL 170 230VLX - VPGND, RILIM2 = 50kΩ (MAX8544 only) -40 -60VLX - VPGND, RILIM2 = 200kΩ (MAX8544 only) -160 -240VLX - VPGND, VFB = 0.8V (MAX8543 only) -110 -150Current-Limit ThresholdVLX - VPGND, VFB = 0V (MAX8543 only) -20 -40mVNegative Current-Limit Threshold % of positive-direction current limit VLX - VPGND -25 -85 %CS+, CS- Input Current VCS+ = VCS- = 0V or 5V -40 +40 µACS+, CS- Input Common-Mode Range 0 13.2 VOSCILLATORSwitching Frequency RFSYNC = 18.2kΩ 800 1200 kHzMinimum Off-Time Measured at DH 150 270 nsMinimum On-Time Measured at DH 140 nsFSYNC Synchronization Range 160 1200 kHzFSYNC Input High Pulse Width 100 nsFSYNC Input Low Pulse Width 100 nsFSYNC Rise/Fall Time 100 nsSYNCO Phase Shift from DH Rising RFSYNC = 18.2kΩ 165 195 DegreesSYNCO Output Low Level ISYNCO = 5mA 0.4 VSYNCO Output High Level ISYNCO = 5mA VVL - 1V VMOSFET DRIVERSDH On-Resistance, High State (VBST - VLX) = 5V 2.5 ΩDH On-Resistance, Low State (VBST - VLX) = 5V 2.5 ΩDL On-Resistance, High State VVL = 5V 2.5 ΩDL On-Resistance, Low State VVL = 5V 1.7 ΩLX, BST, IN Leakage Current VBST = 18.7V, VLX = 13.2V, VIN = 13.2V 5 µA
MAX8543/MAX8544
Step-Down Controllers with Prebias Startup,
Lossless Sensing, Synchronization, and OVP
ELECTRICAL CHARACTERISTICS (continued)
(VIN= 13.2V, VBST- VLX= 5V, TA= -40°C to +85°C,unless otherwise noted.) (Note 2)PARAMETER CONDITIONS MIN MAX UNITSPOKPower-OK Threshold VFB rising, percent of VOUT,
typical hysteresis is 3% 88 94 %POK Output Voltage, Low VFB = 0.6V, IPOK = 2mA 200 mVPOK Leakage Current, High VPOK = 5.5V 1 µAOVERVOLTAGE PROTECTION (OVP)Output Overvoltage Fault-Trip level Rising edge compared to regulation set point;
triggers after one or two clock cycles +110 +120 %MODE CONTROLMODE Logic-Level Low 3V ≤ VVL ≤ 5.5V 0.4 VMODE Logic-Level High 3V ≤ VVL ≤ 5.5V 1.8 VVMODE = 0V -1 +1 MODE Input Current MODE = VL 10 µASHUTDOWN CONTROLEN Logic-Level Low 3V ≤ VVL ≤ 5.5V 0.45 VEN Logic-Level High 3V ≤ VVL ≤ 5.5V 2 VVEN = 0V or 5.5V -1 +4 EN Input Current VEN = 13.2V 6 µA
Note 1:Maximum output voltage is limited by maximum duty cycle and external components.
Note 2:Specifications to -40°C are guaranteed by design and not production tested.
MAX8543/MAX8544
Step-Down Controllers with Prebias Startup,
Lossless Sensing, Synchronization, and OVP
EFFICIENCY vs. LOAD CURRENT
WITH 12V INPUT
MAX8543 toc01
LOAD CURRENT (A)
EFFICIENCY (%)1
VOUT = 3.3V
VOUT = 2.5V
VOUT = 1.8V
fS = 600kHz
EFFICIENCY vs. LOAD CURRENT
WITH 3.3V INPUT
MAX8543 toc02
LOAD CURRENT (A)
EFFICIENCY (%)1
VOUT = 2.5V
VOUT = 1.8V
fS = 500kHz
VOUT = 1.5V
LOAD REGULATION WITH 12V INPUT
MAX8543 toc03
LOAD CURRENT (A)
OUTPUT VOLTAGE (V)963
LINE REGULATION WITH 12V INPUT
AND 2.5V OUTPUT
MAX8543 toc04
INPUT VOLTAGE (V)
OUTPUT VOLTAGE (V)
NO LOAD
15A LOAD
LINE REGULATION
3.0V TO 3.6V INPUT
MAX8543 toc05
INPUT VOLTAGE (V)
OUTPUT VOLTAGE (V)
NO LOAD
15A LOAD
fS = 350kHz
15A LOAD
fS = 500kHz
OSCILLATOR FREQUENCY
vs. INPUT VOLTAGE
MAX8543 toc06
INPUT VOLTAGE (V)
OSCILLATOR FREQUENCY (kHz)
TA = +85°C
TA = +25°C
TA = -40°C
R6 = 53.6kΩ
OSCILLATOR FREQUENCY
vs. INPUT VOLTAGE
MAX8543 toc07
INPUT VOLTAGE (V)
OSCILLATOR FREQUENCY (kHz)
R6 = 42.2kΩ
TA = +85°C
TA = -40°CTA = +25°C
Typical Operating Characteristics
(TA = +25°C, unless otherwise noted.)
MAX8543/MAX8544
Step-Down Controllers with Prebias Startup,
Lossless Sensing, Synchronization, and OVP
Typical Operating Characteristics (continued)
(TA = +25°C, unless otherwise noted.)
MAX8544 STEP-LOAD RESPONSE
7.5A TO 15A TO 7.5A (5A/μs)
MAX8543 toc08
VOUT
IOUT
50mV/div
AC-COUPLED
5A/div
10μs/div
MAX8544 STEP-LOAD RESPONSE
1.5A TO 15A TO 1.5A (5A/μs)
MAX8543 toc09
VOUT
IOUT
100mV/div
AC-COUPLED
5A/div
10μs/div
MAX8544 POWER-UP WAVEFORMS
MAX8543 toc10
VIN
VPOK
5V/div
10A/div
2ms/div
VOUT
2V/div
5V/div
MAX8544 POWER-DOWN WAVEFORMS
MAX8543 toc11
VIN
VPOK
5V/div
10A/div
2ms/div
VOUT
2V/div
2V/div
MAX8543 POWER-UP WAVEFORMS
MAX8543 toc12
VIN2V/div
10A/div
2ms/div
VOUT
1V/div
MAX8543 POWER-DOWN WAVEFORMS
MAX8543 toc13
VIN
2V/div
10A/div
2ms/div
VOUT
1V/div
MAX8543/MAX8544
Step-Down Controllers with Prebias Startup,
Lossless Sensing, Synchronization, and OVP
MAX8544 ENABLE WAVEFORMS
MAX8543 toc14
VEN
5V/div
10A/div
2ms/div
VOUT
2V/div
VPOK5V/div
FSYNC AND SYNCO WAVEFORMS
MAX8543 toc15
VOUT1V/div
5V/div
2μs/div
VLX
VSYNCO
10V/div
VFSYNC5V/div
SHORT CIRCUIT AND RECOVERY
MAX8543 toc16
VIN10V/div
12V
1ms/div
VOUT
IIN
1V/div10A/div
10A/div
OVERVOLTAGE PROTECTION
WITH 15A LOAD
MAX8543 toc17
VOUT
5V/div
40μs/div
VDH
VDL
1V/div
10V/div
PREBIASED STARTUP
(OUTPUT PREBIASED AT 1.5V)
MAX8543 toc18
VIN
5V/div
1ms/div
VLX
VDL
2.5V
10V/div
VOUT
5V/div
500mV/div
1.5V
Typical Operating Characteristics (continued)
(TA = +25°C, unless otherwise noted.)
MAX8543/MAX8544
Step-Down Controllers with Prebias Startup,
Lossless Sensing, Synchronization, and OVP
Pin Description
PIN
MAX8543MAX8544NAMEFUNCTION2GNDGround. Connect to the analog ground plane.SS
Soft-Start. Connect a 0.1µF to 1µF ceramic capacitor from SS to GND. This capacitor
sets the soft-start period during startup. See the Startup and Soft-Start section. SS is
internally pulled to GND in shutdown.4COMPCompensation. Connect to an external RC network to compensate the feedback loop.
See the Compensation Design section. COMP is internally pulled to GND in shutdown.FBOutput Feedback. Connect to the center of a voltage-divider connected between OUT
and GND to set the output voltage. The FB threshold voltage is 0.8V.ENEnable. Drive EN logic high to enable the output, or drive logic low for shutdown.
Connect EN to IN for always-on operation.7CS-Negative Differential Current-Sensing Input8CS+Positive Differential Current-Sensing Input9ILIM1—ILIM
Digital Programmable Current-Limit Input for Inductor Current Sensing (VCS+ - VCS-).
See Table 3.12PGNDPower Ground. Connect to the power ground plane and to the source of the low-side
external MOSFETs. Connect PGND to GND at a single point.13DLLow-Side MOSFET Gate-Driver Output. Connect to the gate of the low-side external
MOSFETs. DL is pulled low in shutdown.14VL
Internal 5V Linear-Regulator Output. Connect a 1µF to 10µF ceramic capacitor from
VL to PGND. Connect VL to IN for VIN less than 5.5V. VL provides power for bias and
gate drive.15INInput Supply Voltage. IN is the input to the internal linear regulator. Connect VL to IN for
VIN less than 5.5V.
BODE PLOT, 600kHz, 15A LOAD
MAX8543 toc19
1kHz1MHz100kHz10kHz
0dB
10dB/div
90°
30°/div
SWEEP TIME
10.000s
BODE PLOT, 600kHz, NO LOAD
MAX8543 toc20
1kHz1MHz100kHz10kHz
0dB90°
30°/div
SWEEP TIME
10.000s
10dB/div
Typical Operating Characteristics (continued)
(TA = +25°C, unless otherwise noted.)
MAX8543/MAX8544
Step-Down Controllers with Prebias Startup,
Lossless Sensing, Synchronization, and OVP
Pin Description (continued)
PIN
MAX8543MAX8544NAMEFUNCTION16LXInductor Connection17DHHigh-Side MOSFET Gate-Driver Output. Connect DH to the gate of the high-side
external MOSFETs. DH is pulled low in shutdown.18BSTBoost Capacitor Connection. Connect a 0.1µF or larger ceramic capacitor from BST to
LX. BST provides power for the high-side MOSFET gate drive.19FSYNC
Frequency Set and Synchronization. Connect a resistor from FSYNC to GND to set the
switching frequency or drive with a clock signal to synchronize between 160kHz and
1.2MHz. See the Switching Frequency and Synchronization section.1ILIM2
Analog Programmable Current-Limit Input for Low-Side MOSFET (VLX - VPGND).
Connect a resistor from ILIM2 to ground to set the overcurrent threshold. See the
Setting the Current Limits section.10MODE
Current-Limit Operating-Mode Selection. Connect MODE to VL for latch-off current limit
or connect to GND for automatic-recovery current limit with the MAX8544. The MAX8543
always uses automatic-recovery current limit.
—11POK
Power-OK. POK is an open-drain output that is high impedance when the output is
above 91% of its nominal regulation voltage. POK is pulled low when the output is out
of regulation and when the part is in shutdown. To use POK as a logic-level signal,
connect a pullup resistor from POK to the logic supply.20SYNCOSynchronization Output. Provides a clock output that is 180° out of phase with the rising
edge of DH for out-of-phase synchronization of another MAX8544.
MAX8543/MAX8544
Step-Down Controllers with Prebias Startup,
Lossless Sensing, Synchronization, and OVP
MAX8544EEP
COMP
MODE
SYNCO
POK
GND
ILIM2
CS-
CS+
PGND
BST
ILIM1
FSYNC
C4AC4BC4C
C6AC6B
SYNC OUT
POK
VOUT = 2.5V
UP TO 15A
VIN = (10.8V TO 13.2V)N1
OFF
SYNC IN
C11
C10
C12
Figure1. Typical Applications Circuit with 12V (±10%) Input, 2.5V Output at Up to 15A, and 600kHz Switching Frequency
MAX8543/MAX8544
Step-Down Controllers with Prebias Startup,
Lossless Sensing, Synchronization, and OVP
Table 1. Suggested Components for Figure 1
DESIGNATIONQTYDESCRIPTION11µF ±20%, 16V X5R ceramic capacitor (0603)
Panasonic ECJ1VB1C105M or equivalent110µF ±20%, 6.3V X5R ceramic capacitor (0805)
Panasonic ECJ2FB0J106M or Taiyo Yuden JMK212BJ106MG10.1µF ±10%, 50V X7R ceramic capacitor (0603)
TDK C1608X7R1H104KT or equivalent
C4A, C4B, C4C210µF ±20%, 16V X5R ceramic capacitors (1206)
Panasonic ECJ3YB1C106M or equivalent10.22µF ±10%, 10V X7R ceramic capacitor (0603)
Taiyo Yuden LMK107BJ224KA or equivalent
C6A, C6B2180µF, 4V aluminum poly SPCAPs
Panasonic EEFUE0G181XR110pF, 50V C0G ceramic capacitor (0603)1220pF ±10%, 50V X7R ceramic capacitor (0603)
C9, C1020.47µF ±10% X7R ceramic capacitors (0603)
C111100pF, 50V C0G ceramic capacitor (0603)
C121470µF ±20%, 16V aluminum electrolytic capacitor
Rubycon 16MBZ470M1100mA, 30V Schottky diode (SOT-323)
Central CMSSH-31250mA, 100V switching diode (SOT23)
Central CMPD91410.82µH, 33A, 1.6mΩ inductor
Vishay IHLP-5050FD-01 0.82µH
N1, N22N-channel MOSFETs
IRF IRF7821
N3, N42N-channel MOSFETs
IRF IRF7832117.4kΩ ±1% resistor (0603)18.06kΩ ±1% resistor (0603)1220kΩ ±5% resistor (0603)
R4, R521.3kΩ ±5% resistors (0603)142.2kΩ ±1% resistor (0603)190.9kΩ ±1% resistor (0603)19.31kΩ ±1% resistor (0603)1100kΩ ±5% resistor (0603)
MAX8543/MAX8544
Step-Down Controllers with Prebias Startup,
Lossless Sensing, Synchronization, and OVP
MAX8543
COMP
CS-
GND
CS+
PGND
BST
ILIM
FSYNC
C4AC4BC4D
C6AC6BVOUT = 2.5V
UP TO 15A
VIN = (3V TO 3.6V)N1
C4CON
OFF
SYNC IN
C12
C11C10
Figure2. Typical Applications Circuit with 3.3V (±10%) Input, 2.5V Output at Up to 15A, and 500kHz Switching Frequency

Partno	Mfg	Dc	Qty	Available	Descript
MAX8544EEP+	MAXIM	N/a	2059	avai	Step-Down Controllers with Prebias Startup, Lossless Sensing, Synchronization, and OVP