MAX38888 Datasheet by Analog Devices Inc./Maxim Integrated

Ordering Information maxim Integrated,“
General Description
The MAX38888 is a storage capacitor or capacitor bank
backup regulator designed to efficiently transfer power be-
tween a storage element and a system supply rail in re-
versible buck and boost operations using the same induc-
tor.
When the main supply is present and above the minimum
system supply voltage, the regulator operates in buck
mode and charges the storage element at up to 500mA
peak inductor current. Once the storage element is
charged, the circuit draws only 2.5µA of current while it
maintains the supercapacitor or other storage element in
its ready state. When the main supply is removed, the reg-
ulator operates in boost mode and prevents the system
from dropping below the minimum operating voltage, dis-
charging the storage element at up to 2.5A peak inductor
current.
The MAX38888 is externally programmable for minimum
and maximum voltage of the storage element, such as
supercapacitor, minimum system voltage, and maximum
charge and discharge currents. The internal DC-DC con-
verter requires only a 1µH inductor.
Applications
● Handheld Industrial Equipment
● Portable Computers
● Portable Devices with a Removable Battery
Benefits and Features
● 2.5V to 5V System Output Voltage
● 0.8V to 4.5V Cap Voltage Range
● Up to 2.5A Peak Inductor Discharge Current
● Programmable Voltage and Current Thresholds
● ±2% Threshold Accuracy
● Up to 95% Efficiency, Charge or Discharge
● 2.5μA Ready Quiescent Current
● Small Solution Size
• 3mm x 3mm x 0.75mm TDFN Package
Ordering Information appears at end of data sheet.
Click here to ask about the production status of specific part numbers.
MAX38888 2.5V to 5.0V, 0.5A/2.5A Reversible Buck/Boost
Regulator for Backup Power Applications
19-100369; Rev 5; 8/20
Typical Application Circuit
C1
22µF
10F
SUPERCAP
VSC
2.7V (MAX)
1.5V (MIN)
MAX38888MAX38888
L1
1µH
VSYS
SYSTEM LOAD
3V (MIN)
R3
1.8MΩ
R2
402kΩ
R1
499kΩ
CAP
FBCL
FBCH
SYS
FBS
ISET
R6
2.49MΩ
R5
499kΩ
R4
20kΩ
LX
DISCHARGE
2.5A (MAX)
CHARGE
500mA (MAX)
MAIN
BATTERY
(REMOVABLE)
GND
ENABLE
INPUT EN
RDY
BKUPB
R7
1MΩ
R8
1MΩ
C2
22µF
READY
BACKUP
MAX38888 2.5V to 5.0V, 0.5A/2.5A Reversible Buck/Boost
Regulator for Backup Power Applications
www.maximintegrated.com Maxim Integrated | 2
2170137 9070063 www. maxfmfntegrated. com/gackages www. maxlmmlegraled. oom/ thermal-lulorla/ Flgure 1
Absolute Maximum Ratings
CAP, EN, SYS, LX, BKUPB, RDY to GND............... -0.3V to +6V
FBCH, FBCL to GND.................................... -0.3V to CAP + 0.3V
FBS, ISET to GND........................................ -0.3V to SYS + 0.3V
PGND to GND ....................................................... -0.3V to +0.3V
Continuous Power Dissipation (TA= +70°C, TDFN,
derate 24.4mW/°C above +70°C) ............................ 1951.2mW
Operating Temperature Range ...........................-40°C to +125°C
Storage Temperature Range ..............................-65°C to +150°C
Maximum Junction Temperature ......................................+150°C
Lead Temperature (soldering, 10 seconds) ......................+300°C
LX RMS Current........................................................... ±2.0ARMS
Output Short-Circuit Duration......................................Continuous
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.
Package Information
TDFN
Package Code T1433+2C
Outline Number 21-0137
Land Pattern Number 90-0063
THERMAL RESISTANCE, FOUR-LAYER BOARD
Junction-to-Ambient (θJA) 41°C/W
Junction-to-Case Thermal Resistance (θJC) 8°C/W
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 thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a
four-layer board. For detailed information on package thermal considerations, refer to www.maximintegrated.com/
thermal-tutorial.
Electrical Characteristics
(VSYS = 3.7V, VCAP = 2.7V, TJ= -40°C to +125°C (typical values at TJ= +25°C), circuit of Figure 1, unless otherwise specified.)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
SYS Voltage Range VVSYS 2.5 5 V
CAP Voltage Range VVSC 0.8 4.5 V
SYS Shutdown Current ISYS_SD
EN = 0V, TA= +25°C 0.01 1 μA
EN = 0V 0.1
SYS Charging Supply
Current ISYS_CHG VFBS = 0.6V, VFBCH = VFBCL = 0.485V 1.5 mA
SYS Backup Supply
Current ISYS_BUP
VFBS = VFBCH = VFBCL = 0.515V, TA=
+25°C 35 65 μA
VFBS = VFBCH = VFBCL = 0.515V 35
SYS Ready Supply
Current ISYS_RDY
VFBS = 0.6V, VFBCH = VFBCL = 0.515V,
TA= +25°C 2.5 5 μA
VFBS = 0.6V, VFBCH = VFBCL = 0.515V 2.5
CAP Shutdown Current ICAP_SD
EN = 0V, TA= +25°C 0.01 1 μA
EN = 0V 0.1
MAX38888 2.5V to 5.0V, 0.5A/2.5A Reversible Buck/Boost
Regulator for Backup Power Applications
www.maximintegrated.com Maxim Integrated | 3
Flgure 1 Flgure 1 Flgure 1 Flgure 1 Flgure 1 Flgure 1 Flgure 1
Electrical Characteristics (continued)
(VSYS = 3.7V, VCAP = 2.7V, TJ= -40°C to +125°C (typical values at TJ= +25°C), circuit of Figure 1, unless otherwise specified.)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
UVLO Threshold VUVLOF VVSYS falling, 100mV typical hysteresis 1.7 1.8 1.9 V
FBS Backup Voltage VFBS FBS rising, when discharging stops -2% 0.5 +2% V
FBS Charging
Threshold VTH_FBS_CHG Above FBS backup voltage, when
charging begins, 30mV typical hysteresis 25 60 95 mV
FBCH Threshold VTH_FBCH FBCH rising, when charging stops, 25mV
typical hysteresis -2% 0.5 +2% V
FBCL Threshold VTH_FBCL FBCL falling, when preserve mode starts,
25mV typical hysteresis -3.5% 0.475 +3.5% V
EN Threshold VIL When LX stops switching, EN falling 225 600 mV
VIH EN rising 660 925
ISET Resistor Range RISET Guaranteed by LX peak current limits 20 100 kΩ
LX Peak Backup
Current Limit (Note 1) IDCHG
Circuit of Figure 1, VCAP = 2V, VSYS =
2.9V, RISET = 20kΩ 2.0 2.5 3.0
A
Circuit of Figure 1, VCAP = 2V, VSYS =
2.9V, RISET = 100kΩ 0.50
LX Peak Charge Current
Limit (Note 1) ICHG
Circuit of Figure 1, VSYS = 3.7V, VCAP =
2V, RISET = 20kΩ 400 500 600
mA
Circuit of Figure 1, VSYS = 3.7V, VCAP =
2V, RISET = 100kΩ 100
FBS/FBCH/FBCL Input
Bias Current
IFBS/FBCH/
FBCL
VFBS/FBCH/FBCL = 0.5V, TA= +25°C -0.1 0.001 0.1 μA
VFBS/FBCH/FBCL = 0.5V 0.01
EN Input Leakage
Current IEN
0V < VEN < 5.5V, TA= +25°C -0.1 0.001 0.1 μA
0V < VEN < 5.5V 0.01
LX Switching Frequency fSW Delivering maximum current from CAP 2 MHz
LX Low-Side FET
Resistance RLOW VSYS = 3V, LX switched to GND 50 100 mΩ
LX High-Side FET
Resistance RHIGH VSYS = 3V, LX switched to SYS 80 160 mΩ
LX Leakage Current ILX_LKG
VEN = 0V, VSYS = 5V, VLX = 0V/5V, TA=
+25°C -1 1 μA
VEN = 0V, VSYS = 5V, VLX = 0V/5V 0.1
Maximum On-Time tON Backup mode, VFBS = 0.485V 320 400 480 ns
Minimum Off-Time tOFF Backup mode, VFBS = 0.485V 80 100 120 ns
Overtemperature
Lockout Threshold TOTLO TJrising, 15°C typical hysteresis 165 °C
High-Side FET Zero-
Crossing (Note 1) IZXP Circuit of Figure 1, VCAP = 2V, VSYS =
2.9V 25 50 75 mA
Low-Side FET Zero-
Crossing (Note 1) IZXN Circuit of Figure 1, VSYS = 3.7V, VCAP =
2V 25 50 75 mA
BKUPB Leakage
Current IBKUPB
VEN = 0V, VBKUPB = 5V, TA= +25°C -1 1 μA
VEN = 0V, VBKUPB = 5V 0.1
MAX38888 2.5V to 5.0V, 0.5A/2.5A Reversible Buck/Boost
Regulator for Backup Power Applications
www.maximintegrated.com Maxim Integrated | 4
Flgure 1
Electrical Characteristics (continued)
(VSYS = 3.7V, VCAP = 2.7V, TJ= -40°C to +125°C (typical values at TJ= +25°C), circuit of Figure 1, unless otherwise specified.)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
BKUPB Output Voltage
Low VBKUPB_L VFBS = 0.48V, VFBCH = VFBCL = 0.515V,
ISINK = 2mA 0.4 V
RDY Leakage Current IRDY
VFBCH = 0.54V, VRDY = 5V, TA= 25°C -1 1 μA
VFBCH = 0.54V, VRDY = 5V 0.1
RDY Output Voltage
Low VRDY_L VEN = 0V, ISINK = 2mA 0.4 V
Note 1: DC measurement, actual zero-crossing, and peak current accuracy in the circuit will be affected by the propagation delay time.
MAX38888 2.5V to 5.0V, 0.5A/2.5A Reversible Buck/Boost
Regulator for Backup Power Applications
www.maximintegrated.com Maxim Integrated | 5
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Typical Operating Characteristics
(VSYS = 3.6V, VCAP = 2.0V, C1 = 22μF, C2 = 22μF, TA= +25°C, unless otherwise noted.)
MAX38888 2.5V to 5.0V, 0.5A/2.5A Reversible Buck/Boost
Regulator for Backup Power Applications
www.maximintegrated.com Maxim Integrated | 6
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Typical Operating Characteristics (continued)
(VSYS = 3.6V, VCAP = 2.0V, C1 = 22μF, C2 = 22μF, TA= +25°C, unless otherwise noted.)
Pin Configuration
MMAAXX3388888888
TTDDFFNN
--
EEPP
33mmmm xx 33mmmm
TOP VIEW
N.C
CAP
N.C
RDY
++
14
LX
BKUPB
13
12
11
10
9
1
2
7
EXPOSED PAD
.
MAX38888 2.5V to 5.0V, 0.5A/2.5A Reversible Buck/Boost
Regulator for Backup Power Applications
www.maximintegrated.com Maxim Integrated | 7
Pin Description
PIN NAME FUNCTION
1 SYS System Supply Rail. Connect to a system supply rail or removable battery between 2.5V and 5V
and bypass with a 22μF capacitor to GND.
2 NC No Connect.
3 BKUPB
Open-Drain Backup Indicator. BKUPB is held low when the part is in backup mode (i.e., when FBS
< 0.5V and FBCL > 0.5V). BKUPB is released high when FBCL < 0.475V or FBS > 0.56V. Connect
to an external pullup resistor.
4 RDY
Open-Drain Supercap Ready Indicator. RDY goes high when the supercapacitor is fully charged
(i.e., FBCH > 0.5V). RDY is pulled low when FBCL < 0.475V. Connect to an external pullup
resistor.
5 ISET Charge/Discharge Current Input. The peak discharge current is set by 50kV/RISET while the peak
charging current is 1/5 the discharging current.
6 FBS SYS Feedback. Connect to the center point of a resistor divider from SYS to GND.
SYS will boost to 0.5V x (1 + RSTop/RSBot) when VFBS < 0.5V.
7 GND Analog Ground.
8 FBCL CAP Feedback. Connect to the upper point of a resistor divider from CAP to GND. Part enters
preserve mode when VFBCL < 0.475V.
9 FBCH CAP Feedback. Connect to the lower point of a resistor divider from CAP to GND. CAP will charge
to 0.5V x (1 + RCTop/RCBot) when VFBS > 0.56V.
10 EN Enable Input. Force this pin high to enable the regulator or force pin low to disable the part and
enter shutdown. If not driven, tie it to the SYS rail.
11 CAP Super Cap. Connect to a supercapacitor rated between 0.8V to 5V with a maximum voltage less
than VSYS.
12 LX Inductor Switching Node. Connect a 1.0μH to 4.7uH inductor from LX to CAP.
13 NC No Connect.
14, EP PGND Power Ground.
MAX38888 2.5V to 5.0V, 0.5A/2.5A Reversible Buck/Boost
Regulator for Backup Power Applications
www.maximintegrated.com Maxim Integrated | 8
Functional Diagram
SYS
LX
PGND
EN
FBS
FBCH
FBCL
CAP BIAS
MODE
SELECT
CONTROL
ISET
BKUPB
GND
RDY
MAX38888
DRIVERS
MAX38888 2.5V to 5.0V, 0.5A/2.5A Reversible Buck/Boost
Regulator for Backup Power Applications
www.maximintegrated.com Maxim Integrated | 9
Detailed Description
The MAX38888 is a flexible storage capacitor or capacitor bank backup regulator efficiently transferring power between
a storage element and a system supply rail.
When the main supply is present and its voltage above the minimum system supply voltage, the regulator operates in the
charging mode of operation and charges the storage element at up to 500mA peak inductor current. Once the storage
element is charged, the RDY flag will assert and the circuit will draw only 2.5μA of current while maintaining the storage
element in its ready state.
When the main supply is removed, the regulator prevents the system from dropping below the minimum operating
voltage, boosting VSYS by discharging the storage element at up to 2.5A peak inductor current. During this backup mode
of operation, the MAX38888 utilizes a fixed on-time, current-limited, pulse-frequency-modulation (PFM) control scheme.
Once MAX38888 is in the backup mode, the BKUPB flag is asserted. When VSYS is applied for the first time, ensure that
the supercapacitor is charged to 2.7V to activate backup mode.
The external pins allow a wide range of system and storage element, such as supercapacitor voltage settings, as well as
charging and discharging peak inductor current settings.
The MAX38888 implements a True Shutdown™ feature, disconnecting VSYS from VCAP as well as protecting against a
SYS short or if VCAP > VSYS.
Application Circuit
The typical application of the MAX38888 is shown in Figure 1.
C1
22µF
10F
SUPERCAP
VSC
2.7V (MAX)
1.5V (MIN)
MAX38888MAX38888
L1
1µH
VSYS
SYSTEM LOAD
3V (MIN)
R3
1.8MΩ
R2
402kΩ
R1
499kΩ
CAP
FBCL
FBCH
SYS
FBS
ISET
R6
2.49MΩ
R5
499kΩ
R4
20kΩ
LX
DISCHARGE
2.5A (MAX)
CHARGE
500mA (MAX)
MAIN
BATTERY
(REMOVABLE)
GND
ENABLE
INPUT EN
RDY
BKUPB
R7
1MΩ
R8
1MΩ
C2
22µF
READY
BACKUP
Figure 1. Typical Application
Supercapacitor Voltage Configuration
The maximum supercapacitor voltage is set using a resistor-divider from CAP to FBCH to GND. The recommended value
for R1 is 499kΩ. Because resistor tolerance will have direct effect on voltage accuracy, these resistors should have 1%
accuracy or better.
R2 + R3 = R1 × ((VCAPMAX
/
0.5) − 1)
MAX38888 2.5V to 5.0V, 0.5A/2.5A Reversible Buck/Boost
Regulator for Backup Power Applications
www.maximintegrated.com Maxim Integrated | 10
’gure 2 Emma! Aggllcat/‘on Circuit
VCAP halts charging when VFBCH reaches 0.5V. The maximum supercapacitor voltage is where the supercapacitor will
remain after it is completely charged and ready for backup.
The minimum supercapacitor discharge voltage is set using a resistor-divider from CAP to FBCL to GND.
R3 = (R1 + R2) × ((VCAPMIN
/
0.5) − 1)
FBCL prevents the supercapacitor from further discharge when VFBCL reaches 0.475V during a backup event in order to
preserve the remaining capacity for keeping alive a real-time clock, memory, or other low-level function. In this preserve
mode, the IC disconnects all circuitry from the supercapacitor and draws 2.5μA current from it.
In applications where SYS voltage needs to be boosted to higher levels, selecting VCAP min has to take into account duty
cycle limitation of the boosting phase, which is 80%. The MAX38888 detects when VSYS falls below VCAP. The device
will not enable if VSYS is below VCAP. Raising VSYS above the backup threshold re-initiates charging and backup.
System Voltage Configuration
The minimum system voltage is set using a resistor-divider from SYS to FBS to GND. The recommended value for R5 is
499kΩ. Because resistor tolerance will have direct effect on voltage accuracy, these resistors should have 1% accuracy
or better.
R6 = R5 × ((VSYSMIN
/
0.5) − 1)
When VFBS is above 0.56V, the DC-DC regulator will draw power from the SYS pin to charge the supercapacitor to the
maximum voltage set by FBCH and be ready for backup. When the main battery is removed, VFBS drops to 0.5V and the
SYS pin is regulated to the programmed minimum voltage with up to 2A of CAP current.
Charge/Discharge Current Configuration
The peak inductor discharge current is set by placing a resistor from ISET to GND. The values of RISET resistor is
calculated by following formula:
IDISCHARGE = 2.5A× (20kΩ
/
RISET)
The supercapacitor charging current is internally set to 1/5 of the discharge current.
ICHARGE = 0.5A× (20kΩ
/
RISET)
the value of RISET between 20kΩ and 100kΩ is recommended to ensure accurate current compliance.
System Waveforms
The waveforms in Figure 2 represent system behavior of the MAX38888 in the Typical Application Circuit.
MAX38888 2.5V to 5.0V, 0.5A/2.5A Reversible Buck/Boost
Regulator for Backup Power Applications
www.maximintegrated.com Maxim Integrated | 11
VSYS
0V
4V
3V
3.36V
3.18V
VCAP
0V
2.7V
BKUPB
0V
1.42V
PRESERVEBACKUPCHARGE LOW CURRENT
RDY
FBCH ≥ 0.5V
FBS ≤ 0.5V
FBCL < 0.475V
Figure 2. System Waveforms
MAX38888 2.5V to 5.0V, 0.5A/2.5A Reversible Buck/Boost
Regulator for Backup Power Applications
www.maximintegrated.com Maxim Integrated | 12
Applications Information
Capacitor Selection
Capacitors at the SYS and CAP pins reduce current peaks and increase efficiency. Ceramic capacitors are
recommended because they have the lowest equivalent series resistance (ESR), smallest size, and lowest cost. Choose
an acceptable dielectric such as X5R or X7R. Due to the ceramic capacitors' capacitance derating with DC bias, standard
22μF ceramic capacitors are recommended at both pins for most applications.
Supercapacitor Selection
When the power source supplying the VSYS voltage is removed, power to the output is provided by the MAX38888
operating in the back-up or boost mode of operation using the supercapacitor as its source. In order to ensure the
supply voltage stays in regulation, the amount of power the supercapacitor can deliver at its minimal voltage should be
greater than that required by the system. The MAX38888 will present a constant power load to the supercapacitor where
smaller current will be pulled out of the supercapacitor near its maximum VCAP voltage. However, current drawn from
the supercapacitor will increase as it discharges to maintain constant power at the load. The amount of energy required
in the backup mode will be the product of the constant backup power and time defined as backup time, tBACKUP.
The amount of energy available in the supercapacitor is calculated using the following formula:
E= 1
/
2 × CSCAP × (VCAPMAX2−VCAPMIN2)(J)
The amount of energy required to complete the backup equals:
E=VSYS ×ISYS ×tBACKUP)(J)
where, ISYS will be the system load during backup.
Since the energy required at the system side during the backup event comes from the available energy in the
supercapacitor, assuming conversion efficiency η and given tBACKUP, the required CSCAP will be determined by the
following equation:
CSCAP = (2xVSYS ×ISYS ×tBACKUP)
/
[(VCAPMAX2–VCAPMIN2) × η](F)
MAX38888 2.5V to 5.0V, 0.5A/2.5A Reversible Buck/Boost
Regulator for Backup Power Applications
www.maximintegrated.com Maxim Integrated | 13
sts , ,,,,,,,,,,,,,,,, ‘ ‘ 7,7,77,77,777777‘, 777777777 i 3 1/99 ,,,,,,, ‘ ‘ 1 1 ,,,,,,,,,, Q W19"L,,,,,"fillfififififififififi, i 1 ‘ ‘ ‘ ‘ ‘ ‘ ‘ ‘ l l ‘ ‘ ‘ l CHARG‘NG CAP l \DLE l BACKUP PRESERVE 1 (BUCKD K NG 1 (aoosn (LOW CURRENT) ‘ ‘ ‘ ngure 1
4
3.36
3
2.7
1.5
0
VOLTAGE (V)
CHARGING CAP
(
BUCK
)
BACKUP
(
BOOST
)
PRESERVE
(
LOW CURRENT
)
V
SYS
V
CAP
IDLE
(
NO SWITCHING
)
LOW IQ
Figure 3. Charging/Discharging Waveforms
For example, in Figure 1 (Application Circuit), the minimum value of the supercapacitor required for 1s backup time,
assuming a 200mA system load and average efficiency of 93%, will be:
CSCAP ≥ (2 × 3.0V× 0.2A× 1s)
/
[((2.7V)2– (1.5V)2) × 0.93] = 256mF
Inductor Selection
The MAX38888 works with a 1μH inductor in most applications. In applications where lower peak currents are desired,
larger inductance may be used in order to reduce the ripple. The recommended inductance range is from 1μH to 4.7μH.
Select 4.7μH for higher RISET value (100kΩ). 1μH is not supported for a 100kΩ RISET value.
Status Flags
The MAX38888 has two dedicated pins to report the device status to the host processor. The ready output (RDY) will be
high when the supercapacitor is fully charged (i.e., FBCH > 0.5V). RDY is pulled low when FBCL < 0.475V. The other
status flag is the Backup Output (BKUPB), which will be held low when the part is in the backup mode (i.e., when FBS <
0.5V and FBCL > 0.5V). BKUPB is released high when FBCL < 0.475V or FBS > 0.56V. Both output pins are open-drain
type and require external pullup resistors. Recommended values for the pullup resistors are 1MΩ. The pins should be
pulled up to the SYS rail.
Enabling Device
The MAX38888 has a dedicated enable pin. The pin can either be driven by a digital signal, pulled up, or strapped to the
SYS rail.
PCB Layout Guidelines
Minimize trace lengths to reduce parasitic capacitance, inductance and resistance, and radiated noise. Keep the main
power path from SYS, LX, CAP, and PGND as tight and short as possible. Minimize the surface area used for LX since
this is the noisiest node. The trace between the feedback resistor-dividers should be as short as possible and should be
isolated from the noisy power path. Refer to the EV kit layout for best practices.
MAX38888 2.5V to 5.0V, 0.5A/2.5A Reversible Buck/Boost
Regulator for Backup Power Applications
www.maximintegrated.com Maxim Integrated | 14
The PCB layout is important for robust thermal design. The junction-to-ambient thermal resistance of the package greatly
depends on the PCB type, layout, and pad connections. Using thick PCB copper and having the SYS, LX, CAP, and
PGND copper pours will enhance the thermal performance. The TDFN package has a large thermal pad under the
package, which creates excellent thermal path to PCB. This pad is electrically connected to PGND. Its PCB pad should
have multiple thermal vias connecting the pad to the internal PGND plane. Thermal vias should either be capped or have
small diameter to minimize solder wicking and voids.
Ordering Information
PART NUMBER TEMP RANGE PIN-PACKAGE FEATURES
MAX38888ATD+ -40°C to +125°C 14 TDFN Enable Input, Selectable Voltages and Currents
+ Denotes a lead(Pb)-free/RoHS-compliant package.
T Denotes tape-and-reel.
MAX38888 2.5V to 5.0V, 0.5A/2.5A Reversible Buck/Boost
Regulator for Backup Power Applications
www.maximintegrated.com Maxim Integrated | 15
Revision History
REVISION
NUMBER
REVISION
DATE DESCRIPTION PAGES
CHANGED
0 6/18 Initial release —
1 7/18 Updated General Description and Benefits and Features 1
2 10/18
Updated General Description,Benefits and Features,Electrical
Characteristics
table, Typical Operating Characteristics,Detailed Description
1, 3–6, 9–12
3 7/19 Updated Supercapacitor Voltage Configuration section 9
4 12/19 Updated Enabling Device section 12
5 8/20 Updated Detailed Description 10
For pricing, delivery, and ordering information, please visit Maxim Integrated’s online storefront at https://www.maximintegrated.com/en/storefront/storefront.html.
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.
MAX38888 2.5V to 5.0V, 0.5A/2.5A Reversible Buck/Boost
Regulator for Backup Power Applications
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