IC Phoenix
 
Home ›  MM69 > MAX651ESA+,5V/3.3V/3V or Adjustable, High-Efficiency, Low-IQ, Step-Down DC-DC Controllers
MAX651ESA+ 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
MAX651ESA+N/AN/a2500avai5V/3.3V/3V or Adjustable, High-Efficiency, Low-IQ, Step-Down DC-DC Controllers


MAX651ESA+ ,5V/3.3V/3V or Adjustable, High-Efficiency, Low-IQ, Step-Down DC-DC ControllersFeaturesThe MAX649/MAX651/MAX652 BiCMOS, step-down DC- ♦ More than 90% Efficiency (10mA to 1.5A Loa ..
MAX652CPA ,5V/3.3V/3V or Adjustable, High-Efficiency,ELECTRICAL CHARACTERISTICS(V+ = 5V, T = T to T , unless otherwise noted. Typical values are at T = ..
MAX652CSA ,5V/3.3V/3V or Adjustable, High-Efficiency,Applications__________Typical Operating Circuit__________________Pin ConfigurationINPUTTOP VIEW4V T ..
MAX652CSA ,5V/3.3V/3V or Adjustable, High-Efficiency,General Description ________
MAX652ESA ,5V/3.3V/3V or Adjustable, High-Efficiency,FeaturesThe MAX649/MAX651/MAX652 BiCMOS, step-down DC- ' More than 90% Efficiency (10mA to 1.5A Loa ..
MAX653CSA+ ,5V/3.3V/3V Adjustable, High-Efficiency, Low-IQ, Step-Down DC-DC Convertersapplications. For increasedoutput drive capability, use the MAX649/MAX651/MAX652MAX639CPA 0°C to +7 ..
MB3120 ,Compandor ICBLOCK DIAGRAM COMPRESSOR EXPANDOH INPUT COMMON MUTE COMPRESSOR', SECTION COMPRESS ..
MB3516A ,RGB EncoderFUJITSU SEMICONDUCTORDS04-28026-2EDATA SHEETASSP Image ControlRGB EncoderMB3516An DESCRIPTIONThe ..
MB3516APF ,RGB EncoderFUJITSU SEMICONDUCTORDS04-28026-2EDATA SHEETASSP Image ControlRGB EncoderMB3516An DESCRIPTIONThe ..
MB3614 ,QUAD OPERATIONAL AMPLIFIERFUJITSU SEMICONDUCTORDS04-11107-3EDATA SHEETLINEAR ICQUAD OPERATIONAL AMPLIFIERMB3614QUAD OPERATION ..
MB3614P ,Quad operational amplifierelectrical characteristics of current industrial standard operational am-DIP-14P-M02plifier and req ..
MB3614P ,Quad operational amplifierFUJITSU SEMICONDUCTORDS04-11107-3EDATA SHEETLINEAR ICQUAD OPERATIONAL AMPLIFIERMB3614QUAD OPERATION ..


MAX651ESA+
5V/3.3V/3V or Adjustable, High-Efficiency, Low-IQ, Step-Down DC-DC Controllers
_______________General Description
The MAX649/MAX651/MAX652 BiCMOS, step-down DC-
DC switching controllers provide high efficiency over
three decades of load current. A unique, current-limited
pulse-frequency-modulated (PFM) control scheme gives
these devices the benefits of pulse-width-modulation
(PWM) converters (high efficiency at heavy loads), while
using only 100μA of supply current (vs. 2mA to 10mA for
PWM converters). The result is high efficiency over loads
ranging from 10mA to more than 2.5A.
These devices use miniature external components.
Their high switching frequency (up to 300kHz) allows
for less than 9mm diameter surface-mount inductors.
The MAX649/MAX651/MAX652 have dropout voltages
less than 1V and accept input voltages up to 16.5V.
Output voltages are preset at 5V (MAX649), 3.3V
(MAX651), and 3V (MAX652). These controllers 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 10W. 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

5V-to-3.3V Green PC Applications
High-Efficiency Step-Down Regulation
Minimum-Component DC-DC Converters
Battery-Powered Applications
____________________________Features
More than 90% Efficiency (10mA to 1.5A Loads)More than 12.5W Output Power100μA Max Quiescent Supply Current5μA Max Shutdown Supply CurrentLess than 1.0V Dropout Voltage16.5V Max Input Voltage5V (MAX649), 3.3V (MAX651), 3V (MAX652),
or Adjustable Output Voltage
Current-Limited Control SchemeUp to 300kHz Switching Frequency
______________Ordering Information
Ordering Information continued at end of data sheet.

* Dice are tested at TA= +25°C.
**Contact factory for availability and processing to MIL-STD-883.V/3.3V/3V or Adjustable, High-Efficiency,
Low IQ, Step-Down DC-DC Controllers
________________________________________________________________Maxim Integrated Products1

GND
EXTREF
SHDN
OUT
DIP/SO

TOP VIEW
MAX649
MAX651
MAX652
__________________Pin Configuration__________Typical Operating Circuit

19-0225; Rev 3; 9/97
PARTTEMP. RANGEPIN-PACKAGE
MAX649CPA
0°C to +70°C8 Plastic DIP
MAX649CSA0°C to +70°C8 SO
MAX649C/D0°C to +70°CDice*
MAX649EPA-40°C to +85°C8 Plastic DIP
MAX649ESA-40°C to +85°C8 SO
MAX649MJA-55°C to +125°C8 CERDIP**
MAX651SHDNGND
ON/OFFEXT
REFOUT
OUTPUT
3.3V
INPUT
4V TO 16.5V
EVALUATION KIT
AVAILABLE
& the latest literature: http://, .
For small orders, phone 1-800-835-8769.
V/3.3V/3V or Adjustable, High-Efficiency,Low IQ, 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 Point
FB Input CurrentIFB
±50±70
±90
Output VoltageVOUT
Supply Current
V+ Input Voltage RangeV+4.016.5V1004
Reference VoltageVREF
REF Load Regulation410mV415
CONDITIONS

MAX649M, MAX65_M
Circuit of
Figure 1
MAX649E, MAX65_E
MAX649C, MAX65_C
V+ = 10V, SHDN ‡1.6V (shutdown)
MAX649C, MAX65_C
MAX649E, MAX65_E
MAX649C, MAX65_C, IREF= 0
MAX649E, MAX65_E, IREF= 0
MAX649M, MAX65_M
MAX649M, MAX65_M, IREF= 0
V+ = 16.5V, SHDN ≤0.4V (operating, switch off)
V+ = 16.5V, 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
CERDIP (derate 8.00mW/°C above +70°C)..................640mW
Operating Temperature Ranges
MAX649C_A, MAX65_C_A..................................0°C to +70°C
MAX649E_A, MAX65_E_A................................-40°C to +85°C
MAX649MJA, MAX65_MJA............................-55°C to +125°C
Storage Temperature Range.............................-65°C to +160°C
Lead Temperature (soldering, 10sec).............................+300°C
MAX649, V+ = 6V to 16.5V
MAX651, V+ = 4V to 16.5V
MAX652, V+ = 4V to 16.5V
MAX649C/E, MAX65_C/E
MAX649M, MAX65_M
0 ≤IREF≤100μA,
sourcing only
4V ≤V+ ≤16.5VREF Line Regulation40100μV/V
mV/V1.7
Output Voltage
Line Regulation
Circuit of
Figure 1
MAX649, 6V ≤V+ ≤16V,
ILOAD= 1A
MAX651, 4.5V ≤V+ ≤16V,
ILOAD= 1A
MAX652, 4V ≤V+ ≤16V,
ILOAD= 1A
V/3.3V/3V or Adjustable, High-Efficiency,Low IQ, Step-Down DC-DC Controllers
_______________________________________________________________________________________3
ELECTRICAL CHARACTERISTICS (continued)

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

UNITS
V+ = 16.5V, SHDN = 0V or V+
SHDN Input Current1μA
Output Voltage
Load Regulation
mV/A
CONDITIONS

Circuit of
Figure 1
MAX649, 0 ≤ILOAD ≤1.5A,
VIN= 10V
MAX651, 0 ≤ILOAD≤1.5A,
VIN= 5V
MAX652, 0 ≤ILOAD≤1.5A,
VIN= 5V
MAX649, V+ = 10V,
ILOAD= 1A
MAX651, V+ = 5V,
ILOAD= 1A89
MAX652, V+ = 5V,
ILOAD= 1A88
EfficiencyCircuit of
Figure 1
4V ≤V+ ≤16.5VSHDN Input Voltage High1.6VVIH
4V ≤V+ ≤16.5V0.4VVILSHDN Input Voltage Low
4V ≤V+ ≤16.5VCS Input Current±1μA
V+ = 12V121620μstON
(max)
Switch Maximum
On-Time
CEXT= 0.001μF, V+ = 12VEXT Rise Time50ns
CEXT= 0.001μF, V+ = 12VEXT Fall Time50ns
V+ = 12VSwitch Minimum
Off-Time1.82.32.8μstOFF
(min)
MAX649C/E, MAX65_C/ECurrent-Limit Trip
Level (V+ to CS)
180210240mVVCSMAX649M, MAX65_M1602102604V ≤V+ ≤16.5V
V/3.3V/3V or Adjustable, High-Efficiency,Low IQ, Step-Down DC-DC Controllers_______________________________________________________________________________________
__________________________________________Typical Operating Characteristics

(TA = +25°C, unless otherwise noted.)
80
SUPPLY CURRENT vs. TEMPERATURE

(m
AX649-A01
TEMPERATURE (°C)100-4008040120
V+ = 10V
V+ = 16.5V
V+ = 4V
SHUTDOWN CURRENT
vs. TEMPERATURE
I+ (m
MAX649-A02
TEMPERATURE (°C)100-4008040120
V+ = 8V
V+ = 16.5V
V+ = 4V
MAX649 MAXIMUM LOAD CURRENT
vs. SUPPLY VOLTAGE
MAX649-A03
INPUT VOLTAGE (V)
(m
VOUT = 5V
CIRCUIT OF FIGURE 1
100m1m10m100m1
MAX649
EFFICIENCY vs. LOAD CURRENT

AX649-A04
LOAD CURRENT (A)
FIC
(%
VIN = 6V
VIN = 8V
VIN = 10V
VIN = 12V
VIN = 15V
VOUT = 5V
TOP TO BOTTOM:
SWITCH ON-TIME
vs. TEMPERATURE

N (m
MAX649-A07
TEMPERATURE (°C)204080100120
V+ = 5V
100m1m10m100m1
MAX651
EFFICIENCY vs. LOAD CURRENT

MAX649-A05
LOAD CURRENT (A)
IEN
Y (%
VIN = 4.3V
VIN = 5V
VIN = 8V
VIN = 10V
VIN = 12V
VIN = 15V
VOUT = 3.3V
TOP TO BOTTOM:
100m1m10m100m1
MAX652
EFFICIENCY vs. LOAD CURRENT

MAX649-A06
LOAD CURRENT (A)
IEN
Y (%
VIN = 4.3V
VIN = 5V
VIN = 8V
VIN = 10V
VIN = 12V
VIN = 15V
VOUT = 3V
TOP TO BOTTOM:
SWITCH OFF-TIME
vs. TEMPERATURE
tOFF (m
AX649-A08
TEMPERATURE (°C)
V+ = 5V
SWITCH ON-TIME/OFF-TIME RATIO
vs. TEMPERATURE
tON
/tOF
F R
TIO7.2
V+ = 5V
MAX649-A9
TEMPERATURE (°C)100-4008040120
V/3.3V/3V or Adjustable, High-Efficiency,Low IQ, Step-Down DC-DC Controllers
_______________________________________________________________________________________5

EXT RISE AND FALL TIMES
vs. TEMPERATURE (1nF)
tRISE &
tFA
LL (ns
MAX649-A10
TEMPERATURE (°C)100-4008040120
V+ = 5V, tRISE
V+ = 5V, tFALL
V+ = 12V, tRISE
V+ = 12V, tFALL
CEXT = 1nF
EXT RISE AND FALL TIMES
vs. TEMPERATURE (5nF)
tRISE &
tFA
LL (ns
AX649-A11
TEMPERATURE (°C)100-4008040120
V+ = 5V, tRISE
V+ = 5V, tFALL
V+ = 12V, tRISE
CEXT = 5nF
V+ = 12V, tFALL
DROPOUT VOLTAGE
vs. LOAD CURRENT
MAX649-A12
LOAD CURRENT (A)
(m
MAX649, VOUT = 5V
MAX652, VOUT = 3V
MAX651, VOUT = 3.3V
DROPOUT VOLTAGE
vs. TEMPERATURE
(m
800MAX651
AX649-A13
TEMPERATURE (°C)100-4008040120
ILOAD = 1A
CIRCUIT OF FIGURE 1
MAX649
MAX652
REFERENCE OUTPUT RESISTANCE
vs. TEMPERATURE
E O
IST
(W
MAX649-A16
TEMPERATURE (°C)100-4008040120
IREF = 10mA
IREF = 50mA
IREF = 100mA
CS TRIP LEVEL
vs. TEMPERATURE
TR
L (m
AX649-A14
TEMPERATURE (°C)100-4008040120
REFERENCE OUTPUT VOLTAGE
vs. TEMPERATURE
T (V1.502
MAX649-A15
TEMPERATURE (°C)100-4008040120
____________________________Typical Operating Characteristics (continued)
(TA = +25°C, unless otherwise noted.)
V/3.3V/3V or Adjustable, High-Efficiency,Low IQ, Step-Down DC-DC Controllers_______________________________________________________________________________________
MAX649
LINE-TRANSIENT RESPONSE

250ms/div
ILOAD = 1A
A: INPUT VOLTAGE (7V & 12V), 5V/div
B: 5V OUT, AC COUPLED, 100mV/div
_____________________________Typical Operating Characteristics (continued)
MAX649
LOAD-TRANSIENT RESPONSE

250ms/div
A: LOAD CURRENT (100mA & 1A), 500mA/div
B: 5V OUTPUT VOLTAGE, AC COUPLED, 50mV/div
______________________________________________________________Pin Description

Positive power-supply inputV+56
Gate drive for external P-channel MOSFET. EXT swings between V+ and GND.EXT7
GroundGND8
1.5V reference output that can source 100μA. Bypass with 0.1μF.REF4
SHDN3
PIN
2
OUT1
FUNCTIONNAME

Sense input for fixed 5V, 3.3V, or 3V output operation. OUT is internally connected to the on-chip voltage divider.
Although it is connected to the output of the circuit, the OUT pin does not supply current.
Feedback 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.
Active-high TTL/CMOS logic-level input. Part is placed in shutdown when SHDN is driven high. In shutdown mode,
the reference and the external MOSFET are turned off, and OUT = 0V. Connect to GND for normal operation.
Current-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.
MAX649
SHUTDOWN RESPONSE TIME

1ms/div
ILOAD = 1A
A: SHDN INPUT VOLTAGE (0V & 5V), 2V/div
B: 5V OUTPUT VOLTAGE, 2V/div
V/3.3V/3V or Adjustable, High-Efficiency,Low IQ, Step-Down DC-DC Controllers
_______________________________________________________________________________________7
_______________Detailed Description

The MAX649/MAX651/MAX652 are BiCMOS, step-
down, switch-mode power-supply controllers that pro-
vide fixed outputs of 5V, 3.3V, and 3V, respectively.
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 MAX649/MAX651/MAX652 offer three main
improvements over prior solutions: The converters operate with tiny (less than 9mm
diameter) 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 (1.0mA to 1.5A).The maximum supply current is only 100μA.
PFM Control Scheme

The MAX649/MAX651/MAX652 use a proprietary, cur-
rent-limited PFM control scheme. As with traditional
PFM converters, 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 (16μs) and
minimum switch off-time (2.3μs). Once off, the minimum
off-time one-shot holds the switch off for 2.3μs. 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 MAX649/MAX651/MAX652 also limit the peak induc-
tor current, which allows them to run in continuous-con-
duction mode and maintain high efficiency with heavy loads
(Figure 3a). 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 (16μs later), or 2) the current limit is reached.
To increase light-load efficiency, the current limit for
the first two pulses is set to half the peak current limit.
If those pulses bring the output voltage into regulation,
the voltage comparator holds the MOSFET off and the
current limit remains at half its peak. If the output vol-
tage is still out of regulation after two pulses, the
current limit for the next pulse is raised to its peak (Figure
3b). Calculate the peak current limit by dividing the
Current-Limit Trip Level (see Electrical Characteristics)
by the value of the current-sense resistor.
Shutdown Mode

When SHDN is high, the MAX649/MAX651/MAX652 enter
shutdown mode. In this mode, the internal biasing circuit-
ry is turned off (including the reference) and the supply
current drops to less than 5μA. EXT goes high, turning off
the external MOSFET. SHDN is a TTL/CMOS logic-level
input. Connect SHDN to GND for normal operation.
Quiescent Current

In normal operation, the quiescent current is less than
100μA. However, this current is measured by forcing
the external transistor switch off. In an actual applica-
tion, even with no load, additional current is drawn to
supply external feedback resistors (if used) and the
diode and capacitor leakage currents. In the circuit of
Figure 1, with V+ at 5V and VOUTat 3.3V, the typical
quiescent current is 90μA.
EXT Drive Voltage Range

EXT swings from V+ to GND and provides the drive out-
put for an external P-channel power MOSFET.
Modes of Operation

When delivering high output currents, the MAX649/
MAX651/MAX652 operate in continuous-conduction
mode (CCM). In this mode, current always flows in the
MAX649
MAX651
MAX652GND8
VIN

330mF
EXT
OUT
SHDN
0.1mF
0.1mF
100mF
0.1W
NSQ03A02L
22mH**
Si9430*OUTPUT
@ 1.5A

*SILICONIX SURFACE-MOUNT MOSFET
**SUMIDA CDR125-220
REF
Figure 1. Test Circuit
V/3.3V/3V or Adjustable, High-Efficiency,Low IQ, Step-Down DC-DC Controllers_______________________________________________________________________________________
MAX649
MAX651
MAX652
MINIMUM
OFF-TIME
ONE-SHOT
TRIG
MAXIMUM
ON-TIME
ONE-SHOT
TRIG
CURRENT
CONTROL CIRCUITS
DUAL-MODE™
COMPARATOR
ERROR
COMPARATOR
CURRENT
COMPARATOR
0.2V
(FULL CURRENT)
0.1V
(HALF CURRENT)S
FROM V+
FROM V+
EXT
OUT
GND
REF
SHDNV+
1.5V
REFERENCE
Figure 2. Block Diagram
ic,good price


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

©2020 IC PHOENIX CO.,LIMITED