19-3997; Rev 5; 8/14
MAX8640Y/MAX8640Z
Tiny 500mA, 4MHz/2MHz Synchronous
Step-Down DC-DC Converters
EVALUATION KIT AVAILABLE
For pricing, delivery, and ordering information, please contact Maxim Direct
at 1-888-629-4642, or visit Maxim’s website at www.maximintegrated.com.
General Description
The MAX8640Y/MAX8640Z step-down converters are
optimized for applications where small size, high effi-
ciency, and low output ripple are priorities. They utilize
a proprietary PWM control scheme that optimizes the
switching frequency for high efficiency with small exter-
nal components and maintains low output ripple volt-
age at all loads. The MAX8640Z switches at up to
4MHz to allow a tiny 1µH inductor and 2.2µF output
capacitor. The MAX8640Y switches at up to 2MHz for
higher efficiency while still allowing small 2.2µH and
4.7µF components. Output current is guaranteed up to
500mA, while typical quiescent current is 28µA.
Factory-preset output voltages from 0.8V to 2.5V elimi-
nate external feedback components.
Internal synchronous rectification greatly improves effi-
ciency and replaces the external Schottky diode
required in conventional step-down converters. Internal
fast soft-start eliminates inrush current so as to reduce
input capacitor requirements.
The MAX8640Y/MAX8640Z are available in the tiny 6-
pin, SC70 (2.0mm x 2.1mm) and µDFN (1.5mm x
1.0mm) packages. Both packages are lead-free.
Applications
Microprocessor/DSP Core Power
I/O Power
Cell Phones, PDAs, DSCs, MP3s
Other Handhelds Where Space Is Limited
Features
oTiny SC70 and µDFN Packages
o500mA Guaranteed Output Current
o4MHz or 2MHz PWM Switching Frequency
oTiny External Components: 1µH/2.2µF or
2.2µH/4.7µF
o28µA Quiescent Current
oFactory Preset Outputs from 0.8V to 2.5V
o±1% Initial Accuracy
oLow Output Ripple at All Loads
oUltrasonic Skip Mode Down to 1mA Loads
oUltra-Fast Line- and Load-Transient Response
oFast Soft-Start Eliminates Inrush Current
Ordering Information
PART* PIN-
PACKAGE TOP MARK
MAX8640YEXT08+T 6 SC70 ACQ
MAX8640YEXT10+T 6 SC70 ADF
MAX8640YEXT11+T 6 SC70 ACR
MAX8640YEXT12+T 6 SC70 ACS
MAX8640YEXT13+T 6 SC70 ACG
MAX8640YEXT15+T 6 SC70 ADD
MAX8640YEXT16+T 6 SC70 ADB
MAX8640YEXT18+T 6 SC70 ACI
MAX8640YEXT19+T 6 SC70 ACH
MAX8640YEXT82+T 6 SC70 ADJ
GND
OUT
1
+
+
6IN
5GND
LX
GND
OUT
LX
MAX8640Y
MAX8640Z
MAX8640Y
MAX8640Z
SC70
2.0mm x 2.1mm
TOP VIEW
2
3
6
5
4
4
1
2
3SHDN
IN
GND
SHDN
µDFN
1.5mm x 1.0mm
Pin Configurations
L1
1µH OR 2.2µH
C2
2.2µF OR
4.7µF
C1
2.2µF
OUT
LX
GND
IN
SHDN
ON/OFF
MAX8640Y
MAX8640Z
INPUT
2.7V TO 5.5V
OUTPUT
0.8V TO 2.5V
UP TO 500mA
Typical Operating Circuit
Ordering Information continued and Selector Guide appears
at end of data sheet.
*
Contact factory for availability of each version. For 2.85V output
(82 version), request application note that includes limitations
and typical operating characteristics.
+
Denotes a lead(Pb)-free/RoHS-compliant package.
T = Tape and reel.
Note: All devices are specified over the -40°C to +85°C
operating temperature range.
MAX8640Y/MAX8640Z
Tiny 500mA, 4MHz/2MHz Synchronous
Step-Down DC-DC Converters
2Maxim Integrated
ABSOLUTE MAXIMUM RATINGS
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 to GND .................................................................-0.3V to +6V
OUT, SHDN to GND ....................................-0.3V to (VIN + 0.3V)
LX Current (Note 1) ........................................................0.8ARMS
OUTPUT Short Circuit to GND ...................................Continuous
Continuous Power Dissipation (TA= +70°C)
6-Pin SC70 (derate 3.1mW/°C above +70°C)..............245mW
6-Pin µDFN (derate 2.1mW/°C above +70°C) ..............167.7mW
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°C
ELECTRICAL CHARACTERISTICS
(VIN = 3.6V, SHDN = IN, TA= -40°C to +85°C, typical values are at TA= +25°C, unless otherwise noted.) (Note 2)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
Supply Range VIN 2.7 5.5 V
UVLO Threshold UVLO VIN rising, 100mV hysteresis 2.44 2.6 2.70 V
No load, no switching 28 48
TA = +25°C 0.01 0.1
Supply Current ICC SHDN = GND TA = +85°C 0.1
µA
Output Voltage Range VOUT Factory preset 0.8 2.5 V
ILOAD = 0mA, TA = +25°C -1 0 +1
Output Voltage Accuracy
(Falling Edge) ILOAD = 0mA, TA = -40°C to +85°C -2 +2 %
Output Load Regulation
(Voltage Positioning) Equal to inductor DC resistance RLV/A
VIH VIN = 2.7V to 5.5V 1.4
SHDN Logic Input Level VIL VIN = 2.7V to 5.5V 0.4 V
TA = +25°C 0.001 1
SHDN Input Bias Current IIH,IL VIN = 5.5V,
SHDN = GND or IN TA = +85°C 0.01 µA
Minimum Required SHDN Reset
Time tSHDN 10 µs
Peak Current Limit ILIMP pFET switch 590 770 1400 mA
Valley Current Limit ILIMN nFET rectifier 450 650 1300 mA
Rectifier Off-Current Threshold ILXOFF nFET rectifier 10 40 70 mA
RONP pFET switch, ILX = -40mA 0.6 1.2
On-Resistance RONN nFET rectifier, ILX = 40mA 0.35 0.7
Ω
TA = +25°C 0.1 1
LX Leakage Current ILXLKG VIN = 5.5V, LX = GND
to IN, SHDN = GND TA = +85°C 1 µA
tON
(
MIN
)
95
Minimum On and Off Times tOFF
(
MIN
)
95 ns
Thermal Shutdown +160 °C
Thermal-Shutdown Hysteresis 20 °C
Note 1: LX has internal clamp diodes to IN and GND. Applications that forward bias these diodes should not exceed the IC’s package
power-dissipation limit.
Note 2: All devices are 100% production tested at TA= +25°C. Limits over the operating temperature range are guaranteed by design.
MAX8640Y/MAX8640Z
Tiny 500mA, 4MHz/2MHz Synchronous
Step-Down DC-DC Converters
3
Maxim Integrated
Typical Operating Characteristics
(VIN = 3.6V, VOUT = 1.5V, MAX8640Z, L = Murata LQH32CN series, TA= +25°C, unless otherwise noted.)
EFFICIENCY vs. LOAD CURRENT
1.8V OUTPUT
LOAD CURRENT (mA)
EFFICIENCY (%)
MAX8640Y/Z toc01
0
10
20
30
40
50
60
70
80
90
100
0.1 1 10 100 1000
MAX8640YEXT18
5
15
10
25
20
30
35
2.7 3.9 4.33.1 3.5 4.7 5.1 5.5
NO-LOAD SUPPLY CURRENT
vs. SUPPLY VOLTAGE
MAX8640Y/Z toc02
SUPPLY VOLTAGE (V)
SUPPLY CURRENT (μA)
MAX8640YEXT18
MAX8640ZEXT15
SWITCHING FREQUENCY
vs. LOAD CURRENT
LOAD CURRENT (mA)
SWITCHING FREQUENCY (MHz)
MAX8640Y/Z toc03
0 100 200 300 400 500
0.1
1
10
MAX8640ZEXT15
MAX8640YEXT18
OUTPUT VOLTAGE vs. LOAD CURRENT
(VOLTAGE POSITIONING)
LOAD CURRENT (mA)
OUTPUT VOLTAGE (V)
MAX8640Y/Z toc04
0 100 200 300 400 500
1.30
1.35
1.40
1.45
1.50
1.55
MAX8640ZEXT15
ILX
VLX
VOUT
200mA/div
2V/div
20mV/div
(AC-COUPLED)
10
μ
s/div
LIGHT-LOAD SWITCHING WAVEFORMS
(IOUT = 1mA)
MAX8640Y/Z toc05
ILX
VLX
VOUT
200mA/div
2V/div
0V
0mA
20mV/div
(AC-COUPLED)
200ns/div
MEDIUM-LOAD SWITCHING WAVEFORMS
(IOUT = 40mA)
MAX8640Y/Z toc06
ILX
VLX
VOUT
200mA/div
2V/div
0V
0mA
20mV/div
(AC-COUPLED)
200ns/div
HEAVY-LOAD SWITCHING WAVEFORMS
(IOUT = 300mA)
MAX8640Y/Z toc07
MAX8640Y/MAX8640Z
Tiny 500mA, 4MHz/2MHz Synchronous
Step-Down DC-DC Converters
4Maxim Integrated
Typical Operating Characteristics (continued)
(VIN = 3.6V, VOUT = 1.5V, MAX8640Z, L = Murata LQH32CN series, TA= +25°C, unless otherwise noted.)
ILX
IIN
VSHDN
VOUT
100mA/div
500mA/div
1V/div
0V
0mA
0mA
5V/div
20μs/div
LIGHT-LOAD STARTUP WAVEFORM
(100Ω LOAD)
MAX8640Y/Z toc08
ILX
IIN
VSHDN
VOUT
100mA/div
500mA/div
1V/div
0V
0mA
0mA
5V/div
20μs/div
HEAVY-LOAD STARTUP WAVEFORM
(5Ω LOAD)
MAX8640Y/Z toc09
ILX
VOUT
VIN
20mV/div
AC-COUPLED
200mA/div
0mA
1V/div
4V
20μs/div
LINE-TRANSIENT RESPONSE
(4V TO 3.5V TO 4V)
MAX8640Y/Z toc10
IOUT
VOUT
ILX 500mA/div
50m/div
AC-COUPLED
200mA/div
0mA
40μs/div
LOAD-TRANSIENT RESPONSE
(5mA TO 250mA TO 5mA)
MAX8640Y/Z toc11
IOUT
VOUT
ILX 500mA/div
100mV/div
AC-COUPLED
200mA/div
0V
40μs/div
LOAD-TRANSIENT RESPONSE
(10mA TO 500mA TO 10mA)
MAX8640Y/Z toc12
PIN NAME
FUNCTION
1LX
Inductor Connection to the Internal Drains of the p-channel and n-channel MOSFETs. High impedance
during shutdown.
2, 5
GND
Ground. Connect these pins together directly under the IC.
3 OUT Output Sense Input. Bypass with a ceramic capacitor as close as possible to pin 3 (OUT) and pin 2 (GND).
OUT is internally connected to the internal feedback network.
4
SHDN
Acti ve- Low S hutd ow n Inp ut. A l og i c- l ow on S HD N d i sab l es the step - d ow n D C - D C and r esets the l og i c. A l og i c-
hi g h on S HD N enab l es the step - d ow n D C - D C . E nsur e that S HD N i s l ow for ≥ 10µs ( tS H D N
) after V
I N
r i ses ab ove i ts
und er vol tag e l ockout thr eshol d ( U V LO ) to r eset the l og i c. S ee the S hutd ow n M od e secti on for m or e i nfor m ati on.
6IN
Supply Voltage Input. Input voltage range is 2.7V to 5.5V. Bypass with a ceramic capacitor as close as
possible to pin 6 (IN) and pin 5 (GND).
Pin Description
MAX8640Y/MAX8640Z
Tiny 500mA, 4MHz/2MHz Synchronous
Step-Down DC-DC Converters
5
Maxim Integrated
Detailed Description
The MAX8640Y/MAX8640Z step-down converters deliv-
er over 500mA to outputs from 0.8V to 2.5V. They utilize
a proprietary hysteretic PWM control scheme that
switches at up to 4MHz (MAX8640Z) or 2MHz
(MAX8640Y), allowing some trade-off between efficien-
cy and size of external components. At loads below
100mA, the MAX8640Y/MAX8640Z automatically switch
to pulse-skipping mode to minimize the typical quies-
cent current (28µA). Output ripple remains low at all
loads, while the skip-mode switching frequency
remains ultrasonic down to 1mA (typ) loads. Figure 1 is
the simplified functional diagram.
Control Scheme
A proprietary hysteretic PWM control scheme ensures
high efficiency, fast switching, fast transient response,
low output ripple, and physically tiny external compo-
nents. This control scheme is simple: when the output
voltage is below the regulation threshold, the error
comparator begins a switching cycle by turning on the
high-side switch. This switch remains on until the mini-
mum on-time expires and the output voltage is above
the regulation threshold or the inductor current is above
the current-limit threshold. Once off, the high-side
switch remains off until the minimum off-time expires
and the output voltage falls again below the regulation
threshold. During the off period, the low-side synchro-
nous rectifier turns on and remains on until either the
high-side switch turns on again or the inductor current
approaches zero. The internal synchronous rectifier
eliminates the need for an external Schottky diode.
Voltage-Positioning Load Regulation
The MAX8640Y/MAX8640Z utilize a unique feedback
network. By taking DC feedback from the LX node, the
usual phase lag due to the output capacitor is
removed, making the loop exceedingly stable and
allowing the use of very small ceramic output capacitors.
This configuration yields load regulation equal to the
inductor’s series resistance multiplied by the load current.
This voltage-positioning load regulation greatly reduces
overshoot during load transients, effectively halving the
peak-to-peak output-voltage excursions compared to tra-
ditional step-down converters. See the Load-Transient
Response in the
Typical Operating Characteristics
.
Shutdown Mode
A logic-low on SHDN places the MAX8640Y/MAX8640Z
in shutdown mode by disabling the step-down DC-DC
and resetting its logic. In shutdown mode, the supply
current (ICC) is reduced to 0.01µA typical. Additionally,
the power MOSFETs between IN, LX, and GND
(Figure 1) are open such that LX is high impedance.
Ensure that SHDN is low for ≥10µs (tSHDN) after VIN
rises above its undervoltage lockout threshold (UVLO)
to reset the logic. In the majority of systems, this tSHDN
requirement is fulfilled naturally because the upstream
logic controlling SHDN is powered off of the same VIN
as the MAX8640Y/MAX8640Z. However, systems that
want an always on regulator without the burden of
enable/disable logic can use an R and C circuit on
SHDN as shown in Figure 2.
MAX8640Y/MAX8640Z
Tiny 500mA, 4MHz/2MHz Synchronous
Step-Down DC-DC Converters
6Maxim Integrated
Soft-Start
The MAX8640Y/MAX8640Z include internal soft-start
circuitry that eliminates inrush current at startup, reduc-
ing transients on the input source. Soft-start is particu-
larly useful for higher impedance input sources, such
as Li+ and alkaline cells. See the Soft-Start Response
in the
Typical Operating Characteristics
.
Applications Information
The MAX8640Y/MAX8640Z are optimized for use with a
tiny inductor and small ceramic capacitors. The correct
selection of external components ensures high efficien-
cy, low output ripple, and fast transient response.
Inductor Selection
A 1µH inductor is recommended for use with the
MAX8640Z, and 2.2µH is recommended for the
MAX8640Y. A 1µH inductor is physically smaller but
requires faster switching, resulting in some efficiency
loss. Table 1 lists several recommended inductors.
It is acceptable to use a 1.5µH inductor with either the
MAX8640Y or MAX8640Z, but efficiency and ripple
should be verified. Similarly, it is acceptable to use a
3.3µH inductor with the MAX8640Y, but performance
should be verified.
For optimum voltage positioning of load transients,
choose an inductor with DC series resistance in the
75mΩto 150mΩrange. For higher efficiency at heavy
loads (above 200mA) or minimal load regulation (but
some transient overshoot), the resistance should be
kept as low as possible. For light-load applications up
to 200mA, higher resistance is acceptable with very lit-
tle impact on performance.
Capacitor Selection
Output Capacitor
The output capacitor, C2, is required to keep the output
voltage ripple small and to ensure regulation loop sta-
bility. C2 must have low impedance at the switching fre-
quency. Ceramic capacitors are recommended due to
their small size and low ESR. Make sure the capacitor
maintains its capacitance over temperature and DC
bias. Capacitors with X5R or X7R temperature charac-
teristics typically perform well. The output capacitance
can be very low; see the
Selector Guide
for recom-
mended capacitance values. For optimum load-tran-
sient performance and very low output ripple, the output
capacitor value in µF should be equal to or larger than
the inductor value in µH.
MAX8640
SHDN
GND
100kΩ
IN
ESD
DIODE
VIN
4.7nF
Figure 2. Using an R and C circuit to create an always on regu-
lator
PWM
LOGIC
MAX8640Y
MAX8640Z
GND
LX
IN
SHDN
0.6V
OUT
Figure 1. Simplified Functional Diagram
MAX8640Y/MAX8640Z
Tiny 500mA, 4MHz/2MHz Synchronous
Step-Down DC-DC Converters
7
Maxim Integrated
Table 1. Suggested Inductors
MANUFACTURER SERIES INDUCTANCE
(µH)
DC RESISTANCE
(Ω typ)
CURRENT RATING
(mA)
DIMENSIONS
L x W x H (mm)
MIPFT2520D 2.0 0.16 900 2.5 x 2.0 x 0.5
1.5 0.07 1500
2.2 0.08 1300
FDK MIPF2520D
3.3 0.10 1200
2.5 x 2.0 x 1.0
1.0 0.12 1200
1.5 0.16 1000Murata LQM31P
2.2 0.22 900
3.2 x 1.6 x 0.95
1.2 0.08 590
1.5 0.09 520
Sumida CDRH2D09
2.2 0.12 440
3.0 x 3.0 x 1.0
1.0 0.11 1100
1.5 0.13 1000
Taiyo Yuden CKP3216T
2.2 0.14 900
3.2 x 1.6 x 0.9
1.0 0.15 460
GLF201208T 2.2 0.36 300 2.0 x 1.25 x 0.9
1.0 0.07 400
GLF2012T 2.2 0.10 300 2.0 x 1.25 x 1.35
1.0 0.10 800
TDK
GLF251812T 2.2 0.20 600 2.5 x 1.8 x 1.35
1.0 0.05 1000
MDT2520-CR 2.2 0.08 700 2.5 x 2.0 x 1.0
1.0 0.07 1100
TOKO
D2812C 2.2 0.14 770 2.8 x 2.8 x 1.2
Input Capacitor
The input capacitor, C1, reduces the current peaks
drawn from the battery or input power source and
reduces switching noise in the IC. The impedance of C1
at the switching frequency should be kept very low.
Ceramic capacitors are recommended due to their
small size and low ESR. Make sure the capacitor main-
tains its capacitance over temperature and DC bias.
Capacitors with X5R or X7R temperature characteristics
typically perform well. Due to the MAX8640Y/
MAX8640Z soft-start, the input capacitance can be very
low. For optimum noise immunity and low input ripple,
choose a capacitor value in µF that is equal to or larger
than the inductor’s value in µH.
PCB Layout and Routing
High switching frequencies and large peak currents
make PCB layout a very important part of design. Good
design minimizes excessive EMI on the feedback paths
and voltage gradients in the ground plane, both of
which can result in instability or regulation errors.
Connect the inductor, input capacitor, and output
capacitor as close together as possible, and keep their
traces short, direct, and wide. Connect the two GND
pins under the IC and directly to the grounds of the
input and output capacitors. Keep noisy traces, such
as the LX node, as short as possible. Refer to the
MAX8640Z evaluation kit for an example PCB layout
and routing scheme.
MAX8640Y/MAX8640Z
Tiny 500mA, 4MHz/2MHz Synchronous
Step-Down DC-DC Converters
8Maxim Integrated
Selector Guide
RECOMMENDED COMPONENTS
PART OUTPUT
VOLTAGE (V)
FREQUENCY
(MHz) L1 (µH) C2 (µF) TOP MARK
MAX8640YEXT08 0.8 1.2 2.2 10 ACQ
MAX8640YEXT10 1.0 1.6 2.2 4.7 ADF
MAX8640YEXT11 1.1 1.7 2.2 4.7 ACR
MAX8640YEXT12 1.2 1.8 2.2 4.7 ACS
MAX8640YEXT13 1.3 1.9 2.2 4.7 ACG
MAX8640YEXT15 1.5 2.0 2.2 4.7 ADD
MAX8640YEXT16 1.6 2.0 2.2 4.7 ADB
MAX8640YEXT18 1.8 2.0 2.2 4.7 ACI
MAX8640YEXT19 1.9 2.0 2.2 4.7 ACH
MAX8640YEXT24 2.4 2.0 2.2 4.7 ADM
MAX8640YEXT25 2.5 1.7 2.2 4.7 ACJ
MAX8640YEXT82 2.85 1.5 2.2 4.7 ADJ
MAX8640YELT08 0.8 1.2 2.2 10 NB
MAX8640YELT11 1.1 1.7 2.2 4.7 NC
MAX8640YELT12 1.2 1.8 2.2 4.7 ND
MAX8640YELT13 1.3 1.9 2.2 4.7 NE
MAX8640YELT15 1.5 2.0 2.2 4.7 NF
MAX8640YELT16 1.6 2.0 2.2 4.7 NG
MAX8640YELT18 1.8 2.0 2.2 4.7 NH
MAX8640YELT19 1.9 2.0 2.2 4.7 NI
MAX8640YELT25 2.5 1.7 2.2 4.7 NJ
MAX8640YELT82 2.85 1.5 2.2 4.7 OW
MAX8640ZEXT08 0.8 2.4 1 4.7 ACL
MAX8640ZEXT11 1.1 3.4 1 2.2 ACM
MAX8640ZEXT12 1.2 3.6 1 2.2 ACN
MAX8640ZEXT13 1.3 3.7 1 2.2 ACO
MAX8640ZEXT15 1.5 3.9 1 2.2 ACP
MAX8640ZEXT18 1.8 4.0 1 2.2 ACU
MAX8640ZELT08 0.8 2.4 1 4.7 NK
MAX8640ZELT11 1.1 3.4 1 2.2 NL
MAX8640Y/MAX8640Z
Tiny 500mA, 4MHz/2MHz Synchronous
Step-Down DC-DC Converters
9
Maxim Integrated
Ordering Information (continued)
PART* PIN-
PACKAGE TOP MARK
MAX8640YEXT24+T 6 SC70 ADM
MAX8640YEXT25+T 6 SC70 ACJ
MAX8640YELT08+T 6 µDFN NB
MAX8640YELT11+T 6 µDFN NC
MAX8640YELT12+T 6 µDFN ND
MAX8640YELT13+T 6 µDFN NE
MAX8640YELT15+T 6 µDFN NF
MAX8640YELT16+T 6 µDFN NG
MAX8640YELT18+T 6 µDFN NH
MAX8640YELT19+T 6 µDFN NI
MAX8640YELT25+T 6 µDFN NJ
MAX8640YELT82+T 6 µDFN OW
PART* PIN-
PACKAGE TOP MARK
MAX8640ZEXT08+T 6 SC70 ACL
MAX8640ZEXT11+T 6 SC70 ACM
MAX8640ZEXT12+T 6 SC70 ACN
MAX8640ZEXT13+T 6 SC70 ACO
MAX8640ZEXT15+T 6 SC70 ACP
MAX8640ZEXT18+T 6 SC70 ACU
MAX8640ZELT08+T 6 µDFN NK
MAX8640ZELT11+T 6 µDFN NL
MAX8640ZELT12+T 6 µDFN NM
MAX8640ZELT13+T 6 µDFN NN
MAX8640ZELT15+T 6 µDFN NO
MAX8640ZELT18+T 6 µDFN NP
Chip Information
PROCESS: BiCMOS
Selector Guide (continued)
RECOMMENDED COMPONENTS
PART OUTPUT
VOLTAGE (V)
FREQUENCY
(MHz) L1 (µH) C2 (µF) TOP MARK
MAX8640ZELT12 1.2 3.6 1 2.2 NM
MAX8640ZELT13 1.3 3.7 1 2.2 NN
MAX8640ZELT15 1.5 3.9 1 2.2 NO
MAX8640ZELT18 1.8 4.0 1 2.2 NP
*
Contact factory for availability of each version. For 2.85V output
(82 version), request application note that includes limitations
and typical operating characteristics.
+
Denotes a lead(Pb)-free/RoHS-compliant package.
T = Tape and reel.
Note: All devices are specified over the -40°C to +85°C
operating temperature range.
MAX8640Y/MAX8640Z
Tiny 500mA, 4MHz/2MHz Synchronous
Step-Down DC-DC Converters
10 Maxim Integrated
SCOTT SCHROEDER
01/12/12
Package Information
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.
PACKAGE TYPE PACKAGE CODE DOCUMENT NO.
6 µDFN L611-1 21-0147
6 SC70 X6S-1 21-0077
MAX8640Y/MAX8640Z
Tiny 500mA, 4MHz/2MHz Synchronous
Step-Down DC-DC Converters
11
Maxim Integrated
SCOTT SCHROEDER
01/12/12
Package Information (continued)
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.
MAX8640Y/MAX8640Z
Tiny 500mA, 4MHz/2MHz Synchronous
Step-Down DC-DC Converters
12 Maxim Integrated
Package Information (continued)
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.
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 160 Rio Robles, San Jose, CA 95134 USA 1-408-601-1000 ________________________________
13
© 2014 Maxim Integrated Products, Inc. Maxim Integrated and the Maxim Integrated logo are trademarks of Maxim Integrated Products, Inc.
MAX8640Y/MAX8640Z
Tiny 500mA, 4MHz/2MHz Synchronous
Step-Down DC-DC Converters
Revision History
REVISION
NUMBER
REVISION
DATE DESCRIPTION PAGES
CHANGED
3 6/08 Added MAX8640YEXT10+T voltage option 7
4 2/09 Added MAX8640YEXT24+T voltage option and
MAX8640YELT82+MAX8640YEXT82+ (82 = 2.85V), and corrected error 1, 2, 7, 8
5 8/14 Updated Electrical Characteristics table, Pin Description, and Shutdown Mode
sections 2, 5
Mouser Electronics
Authorized Distributor
Click to View Pricing, Inventory, Delivery & Lifecycle Information:
Maxim Integrated:
MAX8640ZELT19+T MAX8640YELT12+T MAX8640YELT18+T MAX8640YEXT12+T MAX8640YEXT13+T
MAX8640YEXT15+T MAX8640YEXT18+T MAX8640YEXT19+T MAX8640YEXT25+T MAX8640ZELT12+T
MAX8640ZELT18+T MAX8640ZEXT12+T MAX8640ZEXT18+T MAX8640YELT82+T MAX8640YEXT16+T
MAX8640ZEXT13+T MAX8640ZEXT12-T MAX8640ZEXT18-T MAX8640YEXT08+T MAX8640YELT15+T
MAX8640ZEXT15+T
