IC Phoenix
 
Home ›  MM28 > MAX1649CSA+-MAX1649ESA+-MAX1651CSA+-MAX1651CSA+T-MAX1651CSA-T-MAX1651ESA+,5V/3.3V or Adjustable, High-Efficiency, Low-Dropout, Step-Down DC-DC Controller
MAX1649CSA+-MAX1649ESA+-MAX1651CSA+-MAX1651CSA+T-MAX1651CSA-T Fast Delivery,Good Price
Part Number:
If you need More Quantity or Better Price,Welcom Any inquiry.
We available via phone +865332716050 Email
Partno Mfg Dc Qty AvailableDescript
MAX1649CSA+ |MAX1649CSAMAXIMN/a185avai5V/3.3V or Adjustable, High-Efficiency, Low-Dropout, Step-Down DC-DC Controller
MAX1649ESA+ |MAX1649ESAMAXIMN/a3000avai5V/3.3V or Adjustable, High-Efficiency, Low-Dropout, Step-Down DC-DC Controller
MAX1649ESA+ |MAX1649ESAMAXN/a289avai5V/3.3V or Adjustable, High-Efficiency, Low-Dropout, Step-Down DC-DC Controller
MAX1651CSA+ |MAX1651CSAMAXIMN/a55avai5V/3.3V or Adjustable, High-Efficiency, Low-Dropout, Step-Down DC-DC Controller
MAX1651CSA+T |MAX1651CSATMAXIMN/a860avai5V/3.3V or Adjustable, High-Efficiency, Low-Dropout, Step-Down DC-DC Controller
MAX1651CSA-T |MAX1651CSATMAXIMN/a1630avai5V/3.3V or Adjustable, High-Efficiency, Low-Dropout, Step-Down DC-DC Controller
MAX1651ESA+ |MAX1651ESAMAXIMN/a20avai5V/3.3V or Adjustable, High-Efficiency, Low-Dropout, Step-Down DC-DC Controller


MAX1649ESA+ ,5V/3.3V or Adjustable, High-Efficiency, Low-Dropout, Step-Down DC-DC ControllerApplications*Dice are tested at T = +25°C.A__________Typical Operating Circuit__________________Pin ..
MAX1649ESA+ ,5V/3.3V or Adjustable, High-Efficiency, Low-Dropout, Step-Down DC-DC ControllerFeaturesThe MAX1649/MAX1651 BiCMOS, step-down, DC-DC ♦ More than 90% Efficiency (10mA to 1.5A Loads ..
MAX164BCNG ,CMOS 12-Bit A/D Converters With Track-and-HoldELECTRICAL CHARACTERISTICS (VDD = +5V i5%, Vss = -11.4V to -15.75V, Slow Memory Mode (see text), ..
MAX164BCNG+ ,CMOS 12-Bit A/D Converters With Track-and-HoldApplications Digital Signal Processing (DSP) Audio and Telecom Processing High Accuracy Proces ..
MAX164BEWG ,CMOS 12-Bit A/D Converters With Track-and-HoldlVI/J X Lan CMOS 12-Bit A/D Converters
MAX164CCNG+ ,CMOS, 5V Input, 100ksps, 12-Bit ADC with Track/Hold and ReferenceELECTRICAL CHARACTERISTICS (VDD = +5V i5%, Vss = -11.4V to -15.75V, Slow Memory Mode (see text), ..
MAX4401AXT-T ,Single/Dual/Quad / Low-Cost / Single-Supply / Rail-to-Rail Op Amps with ShutdownFeaturesThe MAX4400–MAX4403 low-cost, general-purpose op Single +2.5V to +5.5V Supply Voltage Rang ..
MAX4402AKA ,Single/Dual/Quad, Low-Cost, Single-Supply, Rail-to-Rail Op Amps with ShutdownMAX4400–MAX4403 Single/Dual/Quad, Low-Cost, Single-Supply, Rail-to-Rail Op Amps with Shutdown
MAX4402AKA+T ,Single/Dual/Quad, Low-Cost, Single-Supply, Rail-to-Rail Op Amps with ShutdownMAX4400–MAX4403 Single/Dual/Quad, Low-Cost, Single-Supply, Rail-to-Rail Op Amps with Shutdown
MAX4402AKA-T ,Dual, low-cost, single-supply +2.5V to 5.5V, Rail-to-Rail op amp.applications.  0.015% THD with 2kΩ LoadThe MAX4400 single amplifier is available in ultra-small  ..
MAX4402ASA ,Dual, low-cost, single-supply +2.5V to 5.5V, Rail-to-Rail op amp.Applications*Future product—contact factory for availability.Single-Supply Zero-Crossing DetectorsI ..
MAX4402ASA+ ,Single/Dual/Quad, Low-Cost, Single-Supply, Rail-to-Rail Op Amps with ShutdownElectrical Characteristics(V = +5V, V = 0V, V = 0V, V = V /2, R = ∞ connected to V /2, SHDN = V (MA ..


MAX1649CSA+-MAX1649ESA+-MAX1651CSA+-MAX1651CSA+T-MAX1651CSA-T-MAX1651ESA+
5V/3.3V or Adjustable, High-Efficiency, Low-Dropout, Step-Down DC-DC Controller
_______________General Description
The MAX1649/MAX1651 BiCMOS, step-down, DC-DC
switching controllers provide high efficiency over loads
ranging from 1mA to more than 2.5A. A unique, current-
limited pulse-frequency-modulated (PFM) control scheme
gives these devices the benefits of pulse-width-modula-
tion (PWM) converters (high efficiency at heavy loads),
while using only 100µA of supply current (vs. 2mA to
10mA for PWM converters). Dropout performance down
to 300mV is provided by a high switch duty cycle (96.5%)
and a low current-sense threshold (110mV).
A high switching frequency (up to 300kHz) allows these
devices to use miniature external components.
The MAX1649/MAX1651 have dropout voltages less
than 0.3V at 500mA and accept input voltages up to
16V. Output voltages are preset at 5V (MAX1649), or
3.3V (MAX1651). They can also be adjusted to any
voltage from 1.5V to the input voltage by using two
resistors.
These step-down controllers drive external P-channel
MOSFETs at loads greater than 12.5W. If less power is
required, use the MAX639/MAX640/MAX653 step-down
converters with on-chip FETs, which allow up to a
225mA load current.
________________________Applications

PDAs
High-Efficiency Step-Down Regulation
5V-to-3.3V Green PC Applications
Battery-Powered Applications
____________________________Features
More than 90% Efficiency (10mA to 1.5A Loads)More than 12.5W Output PowerLess than 0.3V Dropout Voltage at 500mA100µA Max Quiescent Supply Current5µA Max Shutdown Supply Current16V Max Input Voltage5V (MAX1649), 3.3V (MAX1651), or Adjustable
Output Voltage
Current-Limited Control SchemeUp to 300kHz Switching FrequencyUp to 96.5% Duty Cycle
______________Ordering Information

*Dice are tested at TA= +25°C.
MAX1649/MAX1651
5V/3.3V or Adjustable, High-Efficiency,
Low-Dropout, Step-Down DC-DC Controllers

GND
EXTREF
SHDN
OUT
DIP/SO

TOP VIEW
MAX1649
MAX1651
__________________Pin Configuration__________Typical Operating Circuit

19-0305; Rev 3; 3/09
PARTTEMP RANGEPIN-PACKAGE
MAX1649CPA
0°C to +70°C8 Plastic DIP
MAX1649CSA0°C to +70°C8 SO
MAX1649C/D0°C to +70°CDice*
MAX1649EPA-40°C to +85°C8 Plastic DIP
MAX1649ESA-40°C to +85°C8 SO
MAX1651SHDNGND
ON/OFFEXT
REFOUT
OUTPUT
3.3V
INPUT
3.6V TO 16V
MAX1651CPA
0°C to +70°C8 Plastic DIP
MAX1651CSA0°C to +70°C8 SO
MAX1651C/D0°C to +70°CDice*
MAX1651EPA-40°C to +85°C8 Plastic DIP
MAX1651ESA-40°C to +85°C8 SO
EVALUATION KIT
AVAILABLE
MAX1649/MAX1651
5V/3.3V or Adjustable, High-Efficiency,
Low-Dropout, Step-Down DC-DC Controllers
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS

(V+ = 5V, TA= TMINto TMAX, 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.
PARAMETERSYMBOLMINTYPMAXUNITS

1.46251.51.5375FB Trip Point1.4701.51.530V
FB Input CurrentIFB±50nA±70
Output VoltageVOUT4.805.05.20V
Supply Current
V+ Input Voltage RangeV+3.016V1002
Reference VoltageVREF1.4701.51.530V1.46251.51.5375
REF Load RegulationmV410
CONDITIONS

MAX1649E, MAX1651E
MAX1649, V+ = 5.5V to 16V
MAX1649C, MAX1651C
V+ = 10V, SHDN ≥1.6V (shutdown)
MAX1649C, MAX1651C
MAX1649C, MAX1651C, IREF= 0μA
MAX1649E, MAX1651E
MAX1649E, MAX1651E, IREF= 0μA
VOUT< V+
V+ = 16V, SHDN ≤0.4V (operating, switch off)
V+ = 16V, SHDN ≥1.6V (shutdown)
Supply Voltage, V+ to GND.......................................-0.3V, +17V
REF, SHDN, FB, CS, EXT, OUT.......................-0.3V, (V+ + 0.3V)
Continuous Power Dissipation (TA= +70°C)
Plastic DIP (derate 9.09mW/°C above +70°C).............727mW
SO (derate 5.88mW/°C above +70°C)..........................471mW
Operating Temperature Ranges
MAX1649C_A, MAX1651C_A..............................0°C to +70°C
MAX1649E_A, MAX1651E_A............................-40°C to +85°C
Storage Temperature Range.............................-65°C to +160°C
Lead Temperature (soldering, 10sec).............................+300°C
0µA ≤IREF≤100µA, sourcing only
3V ≤V+ ≤16VREF Line Regulation40100µV/V
mV/V
Output Voltage
Line Regulation
Circuit of
Figure 1
MAX1649, 5.5V ≤V+ ≤16V,
ILOAD= 1A
MAX1651, 3.6V ≤V+ ≤16V,
ILOAD= 1A
mV/A
MAX1649, 0A ≤ILOAD≤1.5A,
VIN= 10V
MAX1651, 0A ≤ILOAD≤1.5A,
VIN= 5V-45
Output Voltage
Load Regulation
Circuit of
Figure 1
MAX1649, V+ = 10V,
ILOAD= 1A
MAX1651, V+ = 5V,
ILOAD= 1A90
EfficiencyCircuit of
Figure 1
SHDN Input CurrentV+ = 16V, SHDN = 0V or V+1µA
SHDN Input Voltage HighVIH3V ≤V+ ≤16V1.6V
SHDN Input Voltage LowVIL3V ≤V+ ≤16V0.4V
MAX1651, V+ = 3.6V to 16V
MAX1649/MAX1651
5V/3.3V or Adjustable, High-Efficiency,
Low-Dropout, Step-Down DC-DC Controllers
ELECTRICAL CHARACTERISTICS (continued)

(V+ = 5V, TA= TMINto TMAX, unless otherwise noted. Typical values are at TA= +25°C.)
PARAMETERSYMBOLMINTYPMAXUNITSCONDITIONS

3V ≤V+ ≤16VCS Input Current±1µA
CEXT= 0.001µF, V+ = 12VEXT Rise Time25ns
CEXT= 0.001µF, V+ = 12VEXT Fall Time25ns
Current-Limit Trip Level
(V+ to CS)mVVCS3V ≤V+ ≤16V80110140
tON
tON+ tOFFx 100%Maximum Duty Cycle9596.5%
80
SUPPLY CURRENT vs. TEMPERATURE

I+ (
MAX1649-TOC06
TEMPERATURE (°C)100-4008040120
V+ = 10V
V+ = 16V
V+ = 4V
SHUTDOWN CURRENT
vs. TEMPERATURE
I+ (
MAX1649-TOC05
TEMPERATURE (°C)100-4008040120
V+ = 8V
V+ = 16V
V+ = 4V
V+ = 12VSwitch Maximum On-Time243240µstON(max)
V+ = 12VSwitch Minimum Off-Time0.81.11.8µstOFF(min)
EXT RISE AND FALL TIMES
vs. TEMPERATURE (1nF)
MAX1649/51-01
TEMPERATURE (°C)
tRISE
& t
FALL
(ns)100-4008040120
V+ = 15V, tFALL
V+ = 15V, tRISE
V+ = 5V, tFALL
V+ = 5V, tRISE
CEXT = 1nF1010k
LOAD CURRENT (mA)
EFFICIENCY (%)
1001k0.1
MAX1649/51-A1
EFFICIENCY
vs. LOAD CURRENT (VOUT = 5V)

VOUT = 5V
CIRCUIT OF
FIGURE 1
TOP TO
BOTTOM:
VIN = 6V
VIN = 8V
VIN = 10V
VIN = 12V
VIN = 15V
__________________________________________Typical Operating Characteristics

(TA = +25°C, unless otherwise noted.)
EXT RISE AND FALL TIMES
vs. TEMPERATURE (5nF)
MAX1649/51-02
tRISE
& t
FALL
(ns)100-4008040120
V+ = 15V, tFALL
V+ = 15V, tRISE
V+ = 5V, tFALL
V+ = 5V, tRISE
CEXT = 5nF1010k
EFFICIENCY (%)
1001k0.1
MAX1649/51-A2
EFFICIENCY
vs. LOAD CURRENT (VOUT = 3.3V)

VOUT = 3.3V
CIRCUIT OF
FIGURE 1
TOP TO
BOTTOM:
VIN = 4.3V
VIN = 5V
VIN = 8V
VIN = 10V
VIN = 12V
VIN = 15V
MAX1649/MAX1651
5V/3.3V or Adjustable, High-Efficiency,
Low-Dropout, Step-Down DC-DC Controllers

SWITCH ON-TIME
vs. TEMPERATURE
MAX1649/51-03
TEMPERATURE (°C)
tON100-4008040120
SWITCH OFF-TIME
vs. TEMPERATURE
MAX1649/51-04
TEMPERATURE (°C)
tOFF100-4008040120
MAXIMUM DUTY CYCLE
vs. TEMPERATURE
MAX1649/51-05
TEMPERATURE (°C)
DUTY CYCLE (%)100-4008040120
CS TRIP LEVEL
vs. TEMPERATURE
MAX1649/51-06
TEMPERATURE (°C)
CS TRIP LEVEL (mV)100-4008040120
DROPOUT VOLTAGE
vs. LOAD CURRENT
MAX1649/51-A3
LOAD CURRENT (A)
DROPOUT VOLTAGE (mV)
VOUT = 4.80V
VOUT = 3.17V
CIRCUIT OF
FIGURE 1
REFERENCE OUTPUT RESISTANCE
vs. TEMPERATURE
REFERENCE OUTPUT RESISTANCE (
MAX1649-TOC07
TEMPERATURE (°C)100-4008040120
IREF = 10μA
IREF = 50μA
IREF = 100μA
REFERENCE OUTPUT VOLTAGE
vs. TEMPERATURE
REFERENCE OUTPUT VOLTAGE (V)
MAX1649-TOC01
TEMPERATURE (°C)100-4008040120
IREF = 10μA
____________________________Typical Operating Characteristics (continued)

(TA = +25°C, unless otherwise noted.)
MAX1649/MAX1651
5V/3.3V or Adjustable, High-Efficiency,
Low-Dropout, Step-Down DC-DC Controllers
____________________________Typical Operating Characteristics (continued)

(TA = +25°C, unless otherwise noted.)
CIRCUIT OF FIGURE 1, ILOAD = 1A
A: VOUT = 5V, 100mV/div, AC-COUPLED
B: V+ = 6V TO 16V, 5V/div
MAX1649
LINE-TRANSIENT RESPONSE

5ms/div
16V
CIRCUIT OF FIGURE 1, V+ = 10V
A: VOUT = 5V, 100mV/div, AC-COUPLED
B: ILOAD = 30mA TO 1.6A, 1A/div
MAX1649
LOAD-TRANSIENT RESPONSE

1.6A
200μs/div
CIRCUIT OF FIGURE 1, V+ = 10V, ILOAD = 1A
MAX1649
SHDN RESPONSE TIME

OUTPUT
SHDN
INPUT
1ms/div
MAX1649/MAX1651
5V/3.3V or Adjustable, High-Efficiency,
Low-Dropout, Step-Down DC-DC Controllers
_______________Detailed Description

The MAX1649/MAX1651 are BiCMOS, step-down,
switch-mode power-supply controllers that provide
adjustable and fixed outputs of 5V and 3.3V, respec-
tively. Their unique control scheme combines the
advantages of pulse-frequency-modulation (low supply
current) and pulse-width-modulation (high efficiency at
high loads). An external P-channel power MOSFET
allows peak currents in excess of 3A, increasing the
output current capability over previous PFM devices.
Figure 2 is the block diagram.
The MAX1649/MAX1651 offer four main improvements
over prior solutions: The converters operate with miniature surface-mount
inductors, due to their 300kHz switching frequency.The current-limited PFM control scheme allows
greater than 90% efficiencies over a wide range of
load currents (10mA to 1.5A).Dropout voltage has been reduced to less than
300mV for many applications.The quiescent supply current is only 100µA.
PFM Control Scheme

The MAX1649/MAX1651 use a proprietary, current-limit-
ed PFM control scheme. As with traditional PFM con-
verters, the external power MOSFET is turned on when
the voltage comparator senses that the output is out of
regulation. However, unlike traditional PFM converters,
switching is accomplished through the combination of a
peak current limit and a pair of one-shots that set the
maximum switch on-time (32µs) and minimum switch
off-time (1.1µs). Once off, the off-time one-shot holds
the switch off for 1.1µs. After this minimum time, the
switch either 1) stays off if the output is in regulation, or
2) turns on again if the output is out of regulation.
The MAX1649/MAX1651 also limit the peak inductor cur-
rent, which allows them to run in continuous-conduction
mode and maintain high efficiency with heavy loads
(Figure 3). This current-limiting feature is a key compo-
nent of the control circuitry. Once turned on, the switch
stays on until either 1) the maximum on-time one-shot
turns it off (32µs later), or 2) the current limit is reached.
EXT swings from V+ to GND and provides the drive out-
put for an external P-channel power MOSFET.
MAX1649
MAX1651GND
VIN

330μF
EXT
OUT
SHDN
0.1μF
0.1μF
100μF
0.05Ω
NSQ03A02L
47μH**
Si9430*OUTPUT
@ 1.5A

*SILICONIX SURFACE-MOUNT MOSFET
**SUMIDA CDRH125-470
REF
Figure 1. Typical Application Circuit
______________________________________________________________Pin Description
NAMEFUNCTION
OUT
Sense Input for fixed 5V or 3.3V output operation. OUT is internally connected to the on-chip voltage divider.
Although it is connected to the output of the circuit, OUT does not supply current. Leave OUT unconnected for
adjustable-output operation.FBFeedback Input. Connect to GND for fixed-output operation. Connect a resistor divider between OUT, FB, and
GND for adjustable-output operation. See Setting the Output Voltagesection.
PIN
SHDNActive-High Shutdown Input. Part is placed in shutdown when SHDN is driven high. In shutdown mode, the refer-
ence, output, and external MOSFET are turned off. Connect to GND for normal operation.REF1.5V Reference Output that can source 100µA. Bypass with 0.1µF.GNDGroundEXTGate Drive for External P-Channel MOSFET. EXT swings between V+ and GND.CSCurrent-Sense Input. Connect current-sense resistor between V+ and CS. When the voltage across the resistor
equals the current-limit trip level, the external MOSFET is turned off.V+Positive Power-Supply Input
ic,good price


TEL:86-533-2716050      FAX:86-533-2716790
   

©2020 IC PHOENIX CO.,LIMITED