MAX863EEE+ Fast Delivery |IC PHOENIX CO.,LIMITED

MAX863EEE+ ,Dual, High-Efficiency, PFM, Step-Up DC-DC ControllerApplications__________Typical Operating Circuit2- and 3-Cell Portable EquipmentOrganizersVINTransla ..
MAX8640YELT12+T ,Tiny 500mA, 4MHz/2MHz Synchronous Step-Down DC-DC ConvertersApplications that forward bias these diodes should not exceed the IC’s packagepower-dissipation lim ..
MAX8640YELT18+ ,Tiny 500mA, 4MHz/2MHz Synchronous Step-Down DC-DC ConvertersApplicationsMAX8640YEXT15+T 6 SC70 ADDMicroprocessor/DSP Core PowerMAX8640YEXT16+T 6 SC70 ADBMAX864 ..
MAX8640YEXT12+T ,Tiny 500mA, 4MHz/2MHz Synchronous Step-Down DC-DC ConvertersApplications that forward bias these diodes should not exceed the IC’s packagepower-dissipation lim ..
MAX8640YEXT13+T ,Tiny 500mA, 4MHz/2MHz Synchronous Step-Down DC-DC ConvertersEVALUATION KIT AVAILABLE MAX8640Y/MAX8640ZTiny 500mA, 4MHz/2MHz Synchronous Step-Down DC-DC Conver ..
MAX8640YEXT15+T ,Tiny 500mA, 4MHz/2MHz Synchronous Step-Down DC-DC ConvertersFeatures♦ Tiny SC70 and µDFN PackagesThe MAX8640Y/MAX8640Z step-down converters areoptimized for
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MB84VD22182EE-90 ,32M (x 8/x16) FLASH MEMORY & 4M (x 8/x16) STATIC RAMFUJITSU SEMICONDUCTORDS05-50204-2EDATA SHEETStacked MCP (Multi-Chip Package) FLASH MEMORY & SRAMCMO ..

MAX863EEE+
Dual, High-Efficiency, PFM, Step-Up DC-DC Controller
_______________General Description
The MAX863 dual-output DC-DC converter contains
two independent step-up controllers in a single com-
pact package. This monolithic Bi-CMOS design draws
only 85µA when both controllers are on. The input
range extends down to 1.5V, permitting use in organiz-
ers, translators, and other low-power hand-held prod-
ucts. The MAX863 provides 90% efficiency at output
loads from 20mA to over 1A. This space-saving device
is supplied in a 16-pin QSOP package that fits in the
same area as an 8-pin SOIC.
The device uses a current-limited, pulse-frequency-
modulated (PFM) control architecture that reduces start-
up surge currents and maintains low quiescent currents
for excellent low-current efficiency. Each controller
drives a low-cost, external, N-channel MOSFET switch,
whose size can be optimized for any output current or
voltage.
In larger systems, two MAX863s can be used to gener-
ate 5V, 3.3V, 12V, and 28V from just two or three bat-
tery cells. An evaluation kit (MAX863EVKIT) is available
to speed designs. For a single-output controller, refer to
the MAX608 and MAX1771 data sheets.
________________________Applications
2- and 3-Cell Portable Equipment
Organizers
Translators
Hand-Held Instruments
Palmtop Computers
Personal Digital Assistants (PDAs)
Dual Supply (Logic and LCD)
____________________________FeaturesSmallest Dual Step-Up Converter: 16-Pin QSOP90% Efficiency1.5V Start-Up Voltage85µA Max Total Quiescent Supply Current1µA Shutdown ModeIndependent Shutdown InputsDrives Surface-Mount, Dual N-Channel MOSFETsLow-Battery Input/Output ComparatorStep-Up/Down Configurable
MAX863
Dual, High-Efficiency, PFM, Step-Up
DC-DC Controller
MAX863
EXT2
CS2
OUT2OUT1
VINN
ON/OFF
FB2
SHDN1
EXT1
CS1
LBO
LOW-BATTERY
DETECTOR OUTPUT
LBI
SENSE1VDD
PGND
BOOT
GNDFB1
SHDN2
REF
__________________Pin Configuration
SENSE1REF
SHDN2
LBI
LBO
FB2
SHDN1
CS2
EXT2
TOP VIEW
MAX863
QSOP
VDD
FB1
EXT1
BOOT
CS1
GND
PGND
__________Typical Operating Circuit
19-1218; Rev 2; 2/98
PART
MAX863C/D
MAX863EEE-40°C to +85°C
0°C to +70°C
TEMP. RANGEPIN-PACKAGE
Dice*
16 QSOP
EVALUATION KIT MANUALAVAILABLE
______________Ordering Information
*Dice are tested at TA= +25°C.
MAX863
Dual, High-Efficiency, PFM, Step-Up
DC-DC Controller
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(VDD= +5V, ILOAD= 0mA, 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.
VDDto GND............................................................-0.3V to +12V
PGND to GND.......................................................-0.3V to +0.3V
SHDN1, SHDN2, SENSE1, LBO to GND................-0.3V to +12V
EXT1, EXT2 to PGND..................................-0.3V to (VDD+ 0.3V)
FB1, FB2, CS1, CS2, SEL,
LBI, BOOT to GND.................................-0.3V to (VDD+ 0.3V)
LBO Continuous Output Current.........................................15mA
EXT1, EXT2 Continuous Output Current.............................50mA
Continuous Power Dissipation (TA= +70°C)
QSOP (derate 8.30mW/°C above +70°C)...................667mW
Operating Temperature Range
MAX863EEE....................................................-40°C to +85°C
Junction Temperature......................................................+150°C
Storage Temperature Range.............................-65°C to +160°C
Lead Temperature (soldering, 10sec).............................+300°C
VDD= OUT1 = BOOT (Note 1)
CONDITIONS
UNITSMINTYPMAXSYMBOLPARAMETER
(Note 2)V2.711VDDVDDInput Voltage
SHDN1= VDD, SHDN2= GND,
measured from VDD3560IDDQuiescent Current
SHDN1= SHDN2= VDD, measured from VDD5085
VIN= 2.7V to 5V, VOUT1= 5V,
ILOAD= 300mA, Figure 2mV/V8Line Regulation
VIN= 3.3V, VOUT1= 5V,
ILOAD= 0mA to 500mA, Figure 2mV/A40Load Regulation210IFB, ILBIFB1, FB2, LBI Input Current
VDD= 1.5VV0.7 x VDDVIH2.7V < VDD< 11V1.6SHDN1, SHDN2,SEL, BOOT
Input High Voltage85100115VCSCS1, CS2 Threshold Voltage1417.522
Logic input = VDDor GND
tONMaximum Switch On-Time125CS1, CS2 Input Current1IISHDN1, SHDN2,SEL, BOOT
Input Current1.2251.251.275VFB, VLBIFB1, FB2, LBI
Threshold Voltage (Note 4)
CLOAD= 1nF, 10% to 90%ns50EXT Rise/Fall Time (Note 5)1.622.4tOFFMinimum Switch Off-Time
FB1 = GNDV4.8555.15VOUT1OUT1 Output Voltage
(Note 3)
FB1 = VDD3.23.33.4
VDD= 1.5VV0.2 x VDDVIL2.7V < VDD< 11V0.4SHDN1, SHDN2,SEL, BOOT
Input Low Voltage
SHDN1= SHDN2= GNDµA1IDD, SHDNShutdown Current5EXT On-Resistance
VLBO= 11V, VLBI> 1.275VµA1ILBOLBO Leakage Current
ILBO,SINK= 1mA, VLBI< 1.225VV0.10.4VLBO,LLBO Low Level
MAX863
Dual, High-Efficiency, PFM, Step-Up
DC-DC Controller
ELECTRICAL CHARACTERISTICS
(VDD= +5V, ILOAD= 0mA, TA= -40°C to +85°C, unless otherwise noted.) (Note 6)
Note 1:When bootstrapped, an internal low-voltage oscillator drives the EXT1 pin rail-to-rail for low supply voltages.
Note 2:For non-bootstrapped operation, VDD> 2.7V is required to allow valid operation of all internal circuitry.
Note 3:For adjustable output voltages, see the Set the Output Voltagesection.
Note 4:Measured with LBI falling. Typical hysteresis is 15mV.
Note 5:EXT1 and EXT2 swing from VDDto GND.
Note 6:Specifications to -40°C are guaranteed by design and not production tested.
VDD= OUT1 (Note 1)1.611
CONDITIONS
VDDInput Voltage(Note 2)V2.811VDD1.211.285VFBFB1, FB2 Threshold Voltage85115VCSCS1, CS2 Threshold Voltage
UNITSMINTYPMAXSYMBOLPARAMETER
FB1 = VDD3.153.45OUT1 Output Voltage
(Note 3)FB1 = GNDV4.85.2VOUT1
SHDN1= SHDN2= VDD, measured from VDD85
Quiescent CurrentSHDN1= VDD, SHDN2= GND,
measured from VDDIDD
SHDN1= SHDN2= GNDµA1IDD, SHDNShutdown Current
__________________________________________Typical Operating Characteristics
(TA = +25°C, unless otherwise noted.)
EFFICIENCY vs. OUTPUT CURRENT
(VOUT1 = 3.3V, BOOTSTRAPPED)
MAX863 toc01
OUTPUT CURRENT (mA)
EFFICIENCY (%)C
VOUT1 = 3.3V
A: VIN = 1.5V
B: VIN = 2.4V
C: VIN = 2.7V0.010.1
EFFICIENCY vs. OUTPUT CURRENT
(VOUT1 = 5.0V, BOOTSTRAPPED)
MAX863 toc02
OUTPUT CURRENT (mA)
EFFICIENCY (%)
VOUT1 = 5.0V
A: VIN = 1.5V
B: VIN = 2.4V
C: VIN = 2.7V
D: VIN = 3.3V
E: VIN = 3.6V
F: VIN = 4.0VE
EFFICIENCY vs. OUTPUT CURRENT
(VOUT1 = 5.0V, NON-BOOTSTRAPPED)
MAX863 toc03
OUTPUT CURRENT (mA)
EFFICIENCY (%)VOUT1 = 5.0V
A: VIN = 2.7V
B: VIN = 3.3V
C: VIN = 3.6V
D: VIN = 4.0VC
MAX863
Dual, High-Efficiency, PFM, Step-Up
DC-DC Controller
____________________________Typical Operating Characteristics (continued)
(TA = +25°C, unless otherwise noted.)
EFFICIENCY vs. OUTPUT CURRENT
(VOUT1 = 12V, NON-BOOTSTRAPPED)
MAX863 toc04
OUTPUT CURRENT (mA)
EFFICIENCY (%)VOUT1 = 5.0V
A: VIN = 2.7V
B: VIN = 3.3V
C: VIN = 3.6V
D: VIN = 4.0V
E: VIN = 6.0VDE
BOOTSTRAPPED-MODE MINIMUM
START-UP INPUT VOLTAGE
vs. OUTPUT CURRENT
MAX863toc05
OUTPUT CURRENT (mA)
START-UP INPUT VOLTAGE (V)
VOUT1 = 3.3V
VOUT1 = 5V
VDD CURRENT
vs. VDD VOLTAGE
MAX863 toc15
VDD VOLTAGE (V)
CURRENT (40246
Cond: Single +5V
BOTH ON
CONVERTER 1 ON
CONVERTER 2 ON
LOAD-TRANSIENT RESPONSE
MAX863 toc08
100μs/div
VOUT1 = 3.3V, IOUT1 = 100mA TO 600mA
A: VOUT1, 100mV/div, 3.3V DC OFFSET
B: IOUT1, 200mA/div
RESPONSE ENTERING/
EXITING SHUTDOWN (BOOTSTRAPPED)
MAX863 toc093.3V
200μs/div
VOUT1 = 3.3V, IOUT1 = 100mA, VIN = 2.4V
A: SHDN1, 5V/div
B: INDUCTOR CURRENT, 2A/div
C: VOUT1, 3.3V OFFSET, 500mV/div
LINE-TRANSIENT RESPONSE
MAX863 toc10
C0A
500μs/div
VOUT1 = 5V, IOUT1 = 800mA
A: VIN = 2.7V TO 3.7V, 500mV/div
B: VOUT1, AC COUPLED, 50mV/div
C: INDUCTOR CURRENT, 2A/div
EXT RISE AND FALL TIMES vs.
SUPPLY VOLTAGE AND MOSFET CAPACITANCE
MAX863 toc07
SUPPLY VOLTAGE (V)
RISE/FALL TIME (ns)8
C,1
C,2
B,1
B,2
A,1
A,2
CondSingle5V
A: 470pF
B: 1.0nF
C: 2.2nF
1: RISE
2: FALL
MAX863
Dual, High-Efficiency, PFM, Step-Up
DC-DC Controller
_______________Detailed Description
The MAX863 dual, bi-CMOS, step-up, switch-mode
power-supply controller provides preset 3.3V, 5V, or
adjustable outputs. Its pulse-frequency-modulated
(PFM) control scheme combines the advantages of low
supply current at light loads and high efficiency with
heavy loads. These attributes make the MAX863 ideal
for use in portable battery-powered systems where
small size and low cost are extremely important, and
where low quiescent current and high efficiency are
needed to maximize operational battery life. Use of
external current-sense resistors and MOSFETs allows
the designer to tailor the output current and voltage
capability for a diverse range of applications.
PFM Control Scheme
Each DC-DC controller in the MAX863 uses a one-shot-
sequenced, current-limited PFM design, as shown in
Figure 1. Referring to the Typical Operating Circuit
(Figure 2) and the switching waveforms (Figures 3a–3f),
the circuit works as follows. Output voltage is sensed
by the error comparator using either an internal voltage
divider connected to SENSE1 or an external voltage
divider connected to FB1. When the output voltage
drops, the error comparator sets an internal flip-flop.
The flip-flop turns on an external MOSFET, which allows
inductor current to ramp-up, storing energy in a mag-
netic field.
______________________________________________________________Pin Description
PIN
Feedback Input for DC-DC Controller 1 in Fixed-Output ModeSENSE11
FUNCTIONNAME
IC Power-Supply InputVDD2
Bootstrap Low-Voltage-Oscillator Enable Input. BOOT is an active-high, logic-level input. It enables the
low-voltage oscillator to allow start-up from input voltages down to 1.5V while in a bootstrapped circuit
configuration. Connect BOOT to GND when in a non-bootstrapped configuration. If BOOT is high, VDD
must be connected to OUT1.
BOOT4
Adjustable Feedback and Preset Output Voltage Selection Input for DC-DC Controller 1. Connect to VDD
for 3.3V preset output or to GND for 5V output. Connect a resistor voltage divider to adjust the output volt-
age. See the section Set the Output Voltage.
FB13
Gate-Drive Output of DC-DC Controller 1. Drives an external N-channel power MOSFET.EXT16
High-Current Ground Return for Internal MOSFET DriversPGND8
Analog Ground for Internal Reference, Feedback, and Control CircuitsGND7
Input to the Current-Sense Comparator of DC-DC Controller 1CS15
Input to the Current-Sense Amplifier of DC-DC Controller 2CS210
Adjustable Feedback Input for DC-DC Controller 2. Connect a resistor voltage divider to adjust the output
voltage. See the section Set the Output Voltage.FB212
Active-Low Shutdown Input for DC-DC Controller 1. Connect to VDDfor normal operation.SHDN111
Low-Battery Comparator Input. When the voltage on LBI drops below 1.25V, LBO sinks current. If unused,
connect to GND.LBI14
Reference Bypass Input. Connect a 0.1µF ceramic capacitor from REF to GND.REF16
Active-Low Shutdown Input for DC-DC Controller 2. Connect to VDDfor normal operation.SHDN215
Low-Battery Output. An open-drain N-channel MOSFET output. Sinks current when the voltage on LBI
drops below 1.25V. If unused, connect to GND.LBO13
Gate-Drive Output of DC-DC Controller 2. Drives an external N-channel power MOSFET.EXT29
MAX863
Dual, High-Efficiency, PFM, Step-Up
DC-DC Controller
The flip-flop resets and turns off the MOSFET when
either a) the voltage across the current-sense resistor
exceeds 100mV, or b) the 17.5µs maximum on-time
one-shot trips. When the MOSFET turns off, the mag-
netic field begins to collapse, and forces current into
the output capacitor and load. As the stored energy is
transferred to the output, the inductor current ramps
down. The output capacitor smoothes out the energy
transfer by storing charge when the diode current is
high, then supplying current to the load during the first
half of each cycle, maintaining a steady output voltage.
Resetting the flip-flop sets the off-time one-shot, dis-
abling the error-comparator output and forcing the
MOSFET off for at least 2µs to enforce a minimum time
for energy transfer to the output. The MAX863 waits
until the output voltage drops again before beginning
another cycle. The MAX863’s switching frequency
depends on the load current and input voltage.TRIG
MAX ON-TIME
ONE-SHOT
LOW-
VOLTAGE
OSCILLATOR
TIMING
BLOCK
BIAS
TIMING
BLOCK
EXT2
PGND
BOOT
EXT1
VDD
ERROR
COMPARATOR
CURRENT-SENSE
COMPARATOR
TRIGQ
MIN ON-TIME
ONE-SHOT
CURRENT-
SENSE
COMPARATOR
ERROR
COMPARATOR
100mV
MAX863
UVLO
100mV
100mV
REF
VDD
GNDSHDN2SHDN1REF
REF
1.25V
REF
FB2
CS2
CS1
SENSE1
FB1
LBO
LBI
VDD - 100mV
REF
Figure 1. Functional Diagram
MAX863
Dual, High-Efficiency, PFM, Step-Up
DC-DC Controller
Continuous/Discontinuous-Conduction
Modes
Each converter in the MAX863 determines from moment
to moment whether to switch or not, waiting until the out-
put voltage drops before initiating another cycle. Under
light loads, the inductor current ramps to zero before the
next cycle; this is discontinuous-conduction mode.
Continuous-conduction mode occurs when the next
switching cycle begins while current is still flowing
through the inductor. The transition point between dis-
continuous- and continuous-conduction mode is deter-
mined by input and output voltages, and by the size of
the inductor relative to the peak switching current. In
general, reducing inductance toward the minimum rec-
ommended value pushes the transition point closer to
the maximum load current. If the inductor value is low
enough or the output/input voltage ratio high enough,
the DC-DC converter may remain in discontinuous-con-
duction mode throughout its entire load range.
The MAX863 transitions into continuous-conduction
mode in two ways, depending on whether preset or
adjustable mode is used and how the external feed-
back network is compensated. Under light loads, the IC
switches in single pulses (Figure 3a). The threshold of
transition into continuous-conduction mode is reached
when the inductor current waveforms are adjacent to
one another, as shown in Figure 3b. As the load
increases, the transition into continuous-conduction
mode progresses by raising the minimum inductor cur-
rent (Figures 3c, 3d). Depending on feedback compen-
sation, transition into continuous-conduction mode may
also progress with grouped pulses (Figures 3e, 3f).
Pulse groups should be separated by less than two or
three switching cycles. Output ripple should not be
significantly more than the single-cycle no-load case.
MAX863
EXT2
CS2
VOUT2 = 3.3VVOUT1 = 5V
VIN = 1.5V TO THE LOWER OF VOUT1 OR VOUT2
N1B
IRF7301
0.1μF
100k
10pF
330μF
10V
≤0.1Ω
50mΩ
165k
N1A
50mΩ
100k
220μF
10V
≤0.1Ω
0.1μF
MBRS340T3
MBRS340T3
10μH
10μH
100μF
10V≤0.1Ω
100μF
10V≤0.1Ω
ON/OFF
FB2
SHDN1
EXT1
CS1
LBO
LOW-BATTERY
DETECTOR OUTPUT
LBI
SENSE1VDD
PGND
BOOT
GNDFB1
SHDN2
REF
Figure 2. Bootstrapped Typical Operating Circuit
MAX863
Dual, High-Efficiency, PFM, Step-Up
DC-DC Controller
MAX863
EXT2
CS2
VOUT2 = 12VVOUT1 = 5V
VIN = 2.7V TO THE LOWER OF VOUT1 OR VOUT2
N1.B
IRF7301
0.1μF
115k
82pF
10pF
100μF
20V≤0.1Ω
50mΩR3
N1.A
50mΩ
100k
220μF
10V≤0.1Ω
MBRS340T3D2
MBRS340T3
10μH
10μH
100μF
10V≤0.1Ω
100μF
10V≤0.1Ω
0.1μF
ON/OFF
FB2
SHDN1
EXT1
CS1
LBO
LOW-BATTERY
DETECTOR OUTPUT
LBI
SENSE1
PGND
VDD
GNDFB1
SHDN2
REF
BOOT
Figure 4a. Non-Bootstrapped Typical Operating Circuit
Figures 3a–3f. MAX863 Switching Waveforms During Transition into Continuous Conduction
VOUT1 = 3.3V
PLOTS a-d: INTERNAL FEEDBACK
PLOTS e-f: UNCOMPENSATED,
EXTERNAL FEEDBACK
A: MOSFET DRAIN, 2V/div
B: VOUT1, 100mV/div, 3.3V DC OFFSET
C: INDUCTOR CURRENT, 1A/div
20μs/div
a) IOUT1 = 287mA
20μs/div
b) IOUT1 = 608mA
20μs/div
c) IOUT1 = 767mA
3.3V
3.3V
20μs/div
d) IOUT1 = 1.01A
20μs/div
e) IOUT1 = 757mA
20μs/div
f) IOUT1 = 881mA

Partno	Mfg	Dc	Qty	Available	Descript
MAX863EEE+ \|MAX863EEE	MAX	N/a	225	avai	Dual, High-Efficiency, PFM, Step-Up DC-DC Controller