MAX1925ETC-T-MAX1926ETC+-MAX1926ETC+T Fast Delivery |IC PHOENIX CO.,LIMITED

MAX1925ETC-T ,Switch-Mode 1-Cell Li+ ChargersApplications12 Thin QFNMAX1925ETC -40°C to +85°C 4.5V to 6.1V4mm x 4mmDigital Cameras12 Thin QFNSel ..
MAX1926ETC ,Switch-Mode 1-Cell Li+ ChargersApplications12 Thin QFNMAX1925ETC -40°C to +85°C 4.5V to 6.1V4mm x 4mmDigital Cameras12 Thin QFNSel ..
MAX1926ETC ,Switch-Mode 1-Cell Li+ ChargersELECTRICAL CHARACTERISTICS(V = V = 0, V = V = V = 5V, V = V = V = 4V, THRM = 10kΩ to GND, C = 100nF ..
MAX1926ETC+ ,Switch-Mode 1-Cell Li+ ChargersELECTRICAL CHARACTERISTICS(V = V = 0, V = V = V = 5V, V = V = V = 4V, THRM = 10kΩ to GND, C = 100nF ..
MAX1926ETC+T ,Switch-Mode 1-Cell Li+ Chargersfeatures include automatic input power♦ Set Charge Current with One Resistordetection (ACON output) ..
MAX1927REUB ,Low-Output-Voltage / 800mA / PWM Step-Down DC-DC ConvertersFeaturesThe MAX1927/MAX1928 800mA step-down converters 800mA Output Currentpower low-voltage micro ..
MAX488EESA ,15kV ESD-Protected / Slew-Rate-Limited / Low-Power / RS-485/RS-422 TransceiversApplicationsMAX481EESA -40°C to +85°C 8 SOLow-Power RS-485 TransceiversOrdering Information continu ..
MAX488EESA+ ,±15kV ESD-Protected, Slew-Rate-Limited, Low-Power, RS-485/RS-422 Transceiversapplications that are not ESD sensitive see the pin-and function-compatible MAX481, MAX483, MAX485, ..
MAX488EESA+T ,±15kV ESD-Protected, Slew-Rate-Limited, Low-Power, RS-485/RS-422 TransceiversELECTRICAL CHARACTERISTICS(V = 5V ±5%, T = T to T , unless otherwise noted.) (Notes 1, 2)CC A MIN M ..
MAX488EPA ,Low-Power / Slew-Rate-Limited RS-485/RS-422 TransceiversFeaturesThe MAX481, MAX483, MAX485, MAX487–MAX491, and' In µMAX Package: Smallest 8-Pin SOMAX1487 a ..
MAX488EPA+ ,±15kV ESD-Protected, Slew-Rate-Limited, Low-Power, RS-485/RS-422 TransceiversApplications:EMI and reduce reflections caused by improperly termi-MAX3460–MAX3464: +5V, Fail-Safe, ..
MAX488ESA ,Low-Power / Slew-Rate-Limited RS-485/RS-422 TransceiversMAX481/MAX483/MAX485/MAX487–MAX491/MAX148719-0122; Rev 5; 2/96Low-Power, Slew-Rate-LimitedRS-485/RS ..

MAX1925ETC-T-MAX1926ETC+-MAX1926ETC+T
Switch-Mode 1-Cell Li+ Chargers
General Description
The MAX1925/MAX1926 single-cell lithium-ion (Li+)
switch-mode battery chargers use an external PMOS
pass element step-down configuration. Charge current
is programmable, and an external capacitor sets the
maximum charge time.
Additional features include automatic input power
detection (ACONoutput), logic-controlled enable, and
temperature monitoring with an external thermistor. The
MAX1925 disables charging for inputs greater than
6.1V, while the MAX1926 charges for inputs between
4.25V and 12V.
The MAX1925/MAX1926 feature two precondition levels
to restore near-dead cells. The devices source 4mA to
a cell that is below 2V while sourcing C/10 to a cell
between 2V and 3V. Full charge current is then applied
above 3V. A CHGoutput drives an LED to indicate
charging (LED on) and fault conditions (LED blinking).
The MAX1925/MAX1926 are available in a 12-pin
4mm ✕4mm thin QFN package and are specified over
the extended temperature range (-40°C to +85°C). An
evaluation kit is available to speed design.
Applications
Digital Cameras
Self-Charging Battery Packs
PDAs
Cradle Chargers
FeaturesSmall (4mm ✕4mm) Package4.25V to 12V Input Range (MAX1926)Overvoltage Lockout at 6.1V (MAX1925)±0.75% Battery Regulation VoltageSet Charge Current with One ResistorAutomatic Input Power SenseLED (or Logic-Out) Charge Status and Fault
IndicatorProgrammable Safety TimerAutorestart at Cell = 4VThermistor Monitor Input
MAX1925/MAX1926
Switch-Mode 1-Cell Li+ Chargers
Ordering Information
MAX1925
MAX1926
INPEXTPGND
INPUT
4.5V TO 12V
LED
CHG
OFFACON
THRM
GND
BATT
1-CELL
Li+
BATTERY
Typical Operating Circuit
19-2556; Rev 1; 10/02
EVALUATION KIT
AVAILABLE
PARTTEMP
RANGE
PIN-
PACKAGE
INPUT
CHARGING
RANGE
MAX1925ETC-40°C to +85°C12 Thin QFN
4mm x 4mm4.5V to 6.1V
MAX1926ETC-40°C to +85°C12 Thin QFN
4mm x 4mm4.25V to 12V
INP
EXTENTHRM
PGND
GND
BATT
MAX1925
MAX1926
CHG
ACON
THIN QFN
Pin Configuration
MAX1925/MAX1926
Switch-Mode 1-Cell Li+ Chargers
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(VPGND= VGND= 0, VINP= VIN= VCHG= 5V, VBATT= VCS= VEN= 4V, THRM = 10kΩto GND, CCT= 100nF, 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.
IN, INP, ACONto GND...........................................-0.3V to +14V
CHG, EXT to PGND...................................-0.3V to (VINP+ 0.3V)
CS, BATT, EN, THRM to GND..................................-0.3V to +6V
CT to GND................................................................-0.3V to +4V
EN, THRM, CT to IN................................................-14V to +0.3V
INP to IN................................................................-0.3V to +0.3V
PGND to GND.......................................................-0.3V to +0.3V
CS to BATT............................................................-0.3V to +0.3V
EXT Continuous RMS Current.........................................±100mA
Continuous Power Dissipation (TA= +70°C)
Exposed Paddle Soldered to Board
(derate 16.9mW/°C above +70°C).............................1349mW
Exposed Paddle Unsoldered
(derate 9mW/°C above +70°C)....................................721mW
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
PARAMETERCONDITIONSMINTYPMAXUNITS
Supply Voltage RangeVINP, VIN (MAX1925 does not charge above 6.1V)4.512.0V
MAX19254.304.504.78VINP, VIN risingMAX19264.004.254.50
MAX19254.174.304.43ACON Trip Point
VINP, VIN fallingMAX19263.904.154.40
Rising5.86.4INP, IN Shutdown ThresholdMAX1925Falling5.35.9V
EN Input ResistanceMAX1926 internally pulled up to 3V125300550kΩ
EN Leakage CurrentMAX1925-1+1µA
EN Logic Input High Threshold2V
EN Logic Input Low Threshold0.8V
DONE state, VBATT = 4.1V2550
EN = GND (Note 1)210BATT + CS Input Current
(Total Current into BATT and CS)VBATT = VINP = VIN = 4V, shutdown (Note 1)210
CS Input CurrentCharging39µA
EN = GND58mA
VBATT = VINP = VIN = 4V, shutdown210µA
VBATT = 4.1V; charging10IN + INP Total Input Current
VBATT = 4.3V; done58mA
VOLTAGE LOOP
Voltage Loop Set Point4.16854.20004.2315V
Voltage Loop Hysteresis15mV
BATT Prequal1 Voltage Threshold1.922.1V
BATT Prequal2 Voltage Threshold2.8533.15V
MAX1925/MAX1926
Switch-Mode 1-Cell Li+ Chargers
ELECTRICAL CHARACTERISTICS (continued)
(VPGND= VGND= 0, VINP= VIN= VCHG= 5V, VBATT= VCS= VEN= 4V, THRM = 10kΩto GND, CCT= 100nF, TA= 0°C to +85°C,
unless otherwise noted. Typical values are at TA= +25°C.)
PARAMETERCONDITIONSMINTYPMAXUNITS
Restart ThresholdCharging restarts when BATT falls to this point3.924.004.08V
BATT Voltage Fault ThresholdIf BATT exceeds this threshold, EXT is high
(external MOSFET is off) and CHG blinks4.2754.3504.425V
CURRENT LOOP
VCS - VBATT, average value132142152CS - BATT Sense ThresholdRise/fall hysteresis30mV
Prequal1 Charge CurrentVBATT < 2V346mA
Average value, 2V < VBATT < 3V (charge current is C/10)14Prequal2 CS - BATT Sense
ThresholdRise/fall hysteresis, 2V < VBATT < 3V12mV
Current Threshold for
Full-Battery IndicationILOAD falling, as percentage of fast charge current61220%
DRIVER FUNCTIONSEXT Sink/Source Current 1 AEXT On-Resistance EXT high or low 5 12 ΩNominal Switching Frequency VBATT = 3.6V, L =10µH 235 kHz
TIMER FUNCTIONS
Full-Time Timeout - tFULLCCT = 100nF3.02hours
Prequal1 TimeoutCCT = 100nFtFULL/1088
(10s)s
Prequal2 TimeoutCCT = 100nFtFULL/17
(10.67 min)min
Timer AccuracyCCT = 100nF for 3 hours-15+15%
CHG Output Low CurrentVCHG = 1V71014mA
CHG Output High Leakage
CurrentVCHG = 12V1µA
CHG Blink Rate - FaultFault state (50% duty cycle), CCT = 100nF0.5Hz
ACON High LeakageVACON = 12V0.011.00µA
ACON Sink CurrentVACON = 0.4V2mA
THERMISTOR MONITOR (Note 2)
THRM Sense Current for Hot
Qualification344.1352.9361.7µA
THRM Sense Current for Cold
Qualification47.5848.8050.02µA
THRM Sense-Voltage Trip Point(Note 3)1.3861.4001.414V
MAX1925/MAX1926
Switch-Mode 1-Cell Li+ Chargers
ELECTRICAL CHARACTERISTICS
(VPGND= VGND= 0, VINP= VIN= VCHG= 5V, VBATT= VCS= VEN= 4V, THRM = 10kΩto GND, CCT= 100nF, TA= -40°C to +85°C,
unless otherwise noted. Typical values are at TA= +25°C.) (Note 4)
PARAMETERCONDITIONSMINTYPMAXUNITS
Supply Voltage RangeVINP, VIN (MAX1925 does not charge above 6.1V)4.512.0V
MAX19254.304.78VINP, VIN risingMAX19264.04.5
MAX19254.174.43ACON Trip point
VINP, VIN fallingMAX19263.94.4
Rising5.86.4INP, IN Shutdown ThresholdMAX1925Falling5.35.9V
EN Input ResistanceMAX1926 internally pulled up to 3V125550kΩ
EN Leakage CurrentMAX1925-1+1µA
EN Logic Input High Threshold2V
EN Logic Input Low Threshold0.8V
DONE State, VBATT = 4.1V50
EN = GND (Note 2)10BATT + CS Input Current
(Total Current into BATT and CS)
VBATT = VINP = VIN = 4V, shutdown (Note 1)10
EN = GND8mA
VBATT = VINP = VIN = 4V, shutdown10µA
VBATT = 4.1V, charging10IN + INP Total Input Current
VBATT = 4.3V, done8mA
VOLTAGE LOOP
Voltage Loop Set Point4.1584.242V
BATT Prequal1 Voltage Threshold1.92.1V
BATT Prequal2 Voltage Threshold2.853.15V
Restart ThresholdCharging restarts when BATT falls to this point3.924.08V
BATT Voltage Fault ThresholdIf BATT exceeds this threshold, EXT is high (external
MOSFET is off) and CHG blinks4.2754.425V
CURRENT LOOP
CS - BATT Sense ThresholdVCS - VBATT, average value127157mV
Prequal1 Charge CurrentVBATT < 2V36mA
Current Threshold for Full-Battery
IndicationILOAD falling, as percentage of fast charge current420%
DRIVER FUNCTIONSEXT On-Resistance EXT high or low 12 Ω
TIMER FUNCTIONS
Timer AccuracyCCT = 100nF for 3 hours-16+16%
CHG Output Low CurrentV CHG = 1V714mA
MAX1925/MAX1926
Switch-Mode 1-Cell Li+ Chargers
Note 1:When the AC adapter is unplugged or if the charger is shut down, BATT drain is less than 10µA.
Note 2:These specifications guarantee the thermistor interface detects a fault at the correct temperature (0°C to +5°C cold temper-
ature and 45°C to +50°C hot temperature) with Philips NTC Thermistor Series 640-6, 2322-640-63103, 10.0K at +25°C, ±5%
(or equivalent).
Note 3:A fault is generated if VTHRMlower than 1.4V during the cold test or higher than 1.4V during the hot test. Hot and cold tests
occur on alternate CT clock transitions.
Note 4:Specifications to -40°C are guaranteed by design and not production tested.
ELECTRICAL CHARACTERISTICS (continued)
(VPGND= VGND= 0, VINP= VIN= VCHG= 5V, VBATT= VCS= VEN= 4V, THRM = 10kΩto GND, CCT= 100nF, TA= -40°C to +85°C,
unless otherwise noted. Typical values are at TA= +25°C.) (Note 4)
PARAMETERCONDITIONSMINTYPMAXUNITS
CHG Output High Leakage
CurrentV CHG = 12V1µA
ACON High LeakageV ACON = 12V1µA
ACON Sink CurrentV ACON = 0.4V2mA
THERMISTOR MONITOR
THRM Sense Current for Hot
Qualification342363µA
THRM Sense Current for Cold
Qualification47.350.3µA
THRM Sense-Voltage Trip Point(Note 3)1.3791.421V
MAX1925/MAX1926
Switch-Mode 1-Cell Li+ Chargers
Typical Operating Characteristics
(Circuit of Figure 1, VSUPPLY= 5V, VBATT= 4V, TA = +25°C, unless otherwise noted.)
CHARGE-CURRENT ACCURACY
vs. SUPPLY VOLTAGE
MAX1925/26 toc01
VSUPPLY (V)
CHARGE-CURRENT ACCURACY (%)106789
VBATT = 4V
CHARGE CURRENT
vs. BATTERY VOLTAGE
MAX1925/26 toc02
BATTERY VOLTAGE (V)
CHARGE CURRENT (A)
VIN = 12V
VIN = 10VVIN = 8VVIN = 5V
SEE THE DROPOUT
BEHAVIOR SECTION
FULL-BATTERY VOLTAGE
vs. SUPPLY VOLTAGE
MAX1925/26 toc03
VSUPPLY (V)
FULL-BATTERY VOLTAGE (V)1056789
SHUTDOWN BATTERY CURRENT
vs. BATTERY VOLTAGE
MAX1925/26 toc04
VBATT (V)
SHUTDOWN BATTERY CURRENT (
EFFICIENCY vs. SUPPLY VOLTAGE
MAX1925/26 toc05
VSUPPLY (V)
EFFICIENCY (%)109876
VBATT = 4V
EFFICIENCY vs. BATTERY VOLTAGE
MAX1925/26 toc06
BATTERY VOLTAGE (V)
EFFICIENCY (%)
VIN = 12V
VIN = 8V
VIN = 5V
SWITCHING FREQUENCY vs. INDUCTANCE
MAX1925/26 toc07
INDUCTANCE (μH)
SWITCHING FREQUENCY (kHz)
VIN = 12V
VIN = 8V
VIN = 5V
VBATT = 4V
SWITCHING FREQUENCY vs. RSENSE
MAX1925/26 toc08
RSENSE (Ω)
SWITCHING FREQUENCY (kHz)
VIN = 12V
VIN = 8V
VIN = 5V
VBATT = 4V
SWITCHING FREQUENCY
vs. SUPPLY VOLTAGE
MAX1925/26 toc09
VSUPPLY (V)
SWITCHING FREQUENCY (kHz)108976
VBATT = 4V
MAX1925/MAX1926
Switch-Mode 1-Cell Li+ Chargers
FREQUENCY vs. BATTERY VOLTAGE
MAX1925/26 toc10
BATTERY VOLTAGE (V)
SWITCHING FREQUENCY (kHz)
VIN = 12V
VIN = 8V
VIN = 5V
TIMER vs. CT CAPACITANCE
MAX1925/26 toc11
CT CAPACITANCE (nF)
TIMER (MINUTES)
tFULLCHG
tPREQUAL2
tPREQUAL1
CHARGE CURRENT vs. TIME
MAX1925/26 toc12
TIME (h)
CHARGE CURRENT (A)
BATTERY VOLTAGE vs. TIME
MAX1925/26 toc13
TIME (h)
BATTERY VOLTAGE (A)
SWITCHING WAVEFORM
MAX1925/26 toc14
4μs/div
1.2A
0.8A
10V
100mV/
div
INDUCTOR
CURRENT
VLX
VBATT
VIN = 5V
SWITCHING WAVEFORM
MAX1925/26 toc15
1μs/div
1.2A
1.4A
0.8A
10V
100mV/
div
INDUCTOR
CURRENT
VLX
VBATT
VIN = 12V
CHARGE-ENABLE REPSONSE
MAX1925/26 toc16
INDUCTOR
CURRENTypical Operating Characteristics (continued)
(Circuit of Figure 1, VSUPPLY= 5V, VBATT= 4V, TA = +25°C, unless otherwise noted.)
MAX1925/MAX1926
Switch-Mode 1-Cell Li+ Chargers
Pin Description
PINNAMEFUNCTIONCHG
Charge Status LED Driver. Open-drain LED driver sinks 10mA when the MAX1925/MAX1926 are charging.
CHG also blinks at a 0.5Hz rate during fault states (see the Timing section). High impedance when charger is
in shutdown. See Tables 1 and 2.
2ENEnable. Drive EN high to enable charger. Logic level input for normal ON/OFF control. In the MAX1926 EN is
internally pulled up to 3V with a 300kΩ resistor.THRM
Thermistor Input. Monitors external thermistor (10kΩ at +25°C). When external temperature is lower than 0°C
or above +50°C, charging stops and the charger enters fault mode. Charging resumes when the temperature
returns to normal. During a temperature fault the MAX1926 blinks the CHG output, while MAX1925 CHG
remains off (high).ACONPower-OK Indicator Output. Open-drain output goes low when AC adapter power is valid. See Table 2 for
ACON states.
5CT
Timing Capacitor Connection. Connect timer cap to program full-charge safety timeout interval and
prequalification fault times. Timeouts with CCT = 100nF are:
Full Timer (tFULLCHG): 3 hours—If FASTCHG is not completed within this time a fault is asserted.
Prequal2 Timer: Full Timer/17 (10.67 min)
Prequal1 Timer: Full Timer/1088 (10s)CSCharge-Current Sense Input. 142mV nominal regulation threshold. CS is high impedance during shutdown.BATTBattery-Sense Input. Also negative side of charge-current sense. BATT is high impedance during shutdown.GNDGroundPGNDPower GroundEXTPMOS Gate-Driver Output. Drives gate of external PMOS switching transistor from IN to GND. When using the
MAX1926, ensure that the MOSFET VGS rating is greater than VIN.INPSupply Voltage InputINSupply-Sense Input. Connect IN to INP.

Partno	Mfg	Dc	Qty	Available	Descript
MAX1925ETC-T \|MAX1925ETCT	MAXIM	N/a	263	avai	Switch-Mode 1-Cell Li+ Chargers
MAX1926ETC+	MAXIM	N/a	72	avai	Switch-Mode 1-Cell Li+ Chargers
MAX1926ETC+T	MAXIM	N/a	140	avai	Switch-Mode 1-Cell Li+ Chargers