MAX856CSA-T ,3.3V/5V or Adjustable Output, Step-Up DC-DC ConvertersGeneral Description ________
MAX856CUA ,3.3V/5V or Adjustable-Output, Step-Up DC-DC ConvertersApplicationsMAX856C/D 0°C to +70°C Dice*3.3V to 5V Step-Up ConversionMAX856ESA -40°C to +85°C 8 SOP ..
MAX856CUA+ ,3.3V/5V or Adjustable Output, Step-Up DC-DC ConvertersApplicationsMAX856C/D 0°C to +70°C Dice*3.3V to 5V Step-Up ConversionMAX856ESA -40°C to +85°C 8 SOP ..
MAX856CUA-T ,3.3V/5V or Adjustable Output, Step-Up DC-DC ConvertersELECTRICAL CHARACTERISTICS(Circuits of Figure 2, V = 2.5V, I = 0mA, T = T to T , unless otherwise n ..
MAX856ESA ,3.3V/5V or Adjustable-Output, Step-Up DC-DC ConvertersMAX856–MAX85919-0211; Rev 4; 5/963.3V/5V or Adjustable-Output, Step-Up DC-DC Converters____________ ..
MAX856ESA+ ,3.3V/5V or Adjustable Output, Step-Up DC-DC ConvertersGeneral Description ________
MB84256A-10LLP , CMOS 256K-BIT LOW POWER SRAM
MB84256A-10LPF , CMOS 256K-BIT LOW POWER SRAM
MB84VD21183EM-70PBS , Stacked MCP (Multi-Chip Package) FLASH MEMORY & SRAM CMOS
MB84VD21194EM-70PBS , Stacked MCP (Multi-Chip Package) FLASH MEMORY & SRAM CMOS
MB84VD22181FM-70PBS , 32M (X16) FLASH MEMORY & 4M (X16) STATIC RAM
MB84VD22182EE-90 ,32M (x 8/x16) FLASH MEMORY & 4M (x 8/x16) STATIC RAMFUJITSU SEMICONDUCTORDS05-50204-2EDATA SHEETStacked MCP (Multi-Chip Package) FLASH MEMORY & SRAMCMO ..
MAX856CSA+-MAX856CSA+T-MAX856CSA-T-MAX856CUA+-MAX856CUA-T-MAX856ESA+-MAX856ESA+T-MAX857CSA+-MAX857ESA+-MAX857ESA+T-MAX858CSA+-MAX858CSA+T-MAX859CPA-MAX859ESA+
3.3V/5V or Adjustable Output, Step-Up DC-DC Converters
_______________General DescriptionThe MAX856–MAX859 are high-efficiency, CMOS, step-
up, DC-DC switching regulators for small, low input volt-
age or battery-powered systems. The MAX856/MAX858
accept a positive input voltage between 0.8V and VOUT
and convert it to a higher, pin-selectable output voltage of
3.3V or 5V. The MAX857/MAX859 adjustable versions
accept 0.8V to 6.0V input voltages and generate higher
adjustable output voltages in the 2.7V to 6.0V range.
Typical efficiencies are greater than 85%. Typical quies-
cent supply current is 25µA (1µA in shutdown).
The MAX856–MAX859 combine ultra-low quiescent supply
current and high efficiency to give maximum battery life. An
internal MOSFET power transistor permits high switching
frequencies. This benefit, combined with internally set peak
inductor current limits, permits the use of small, low-cost
inductors. The MAX856/MAX857 have a 500mA peak
inductor current limit. The MAX858/MAX859 have a 125mA
peak inductor current limit.
________________________Applications3.3V to 5V Step-Up Conversion
Palmtop Computers
Portable Data-Collection Equipment
Personal Data Communicators/Computers
Medical Instrumentation
2-Cell & 3-Cell Battery-Operated Equipment
Glucose Meters
____________________________Features0.8V to 6.0V Input Supply Voltage0.8V Typ Start-Up Supply Voltage85% Efficiency at 100mA25µA Quiescent Current1µA Shutdown Mode125mA and 500mA Switch-Current Limits Permit
Use of Low-Cost InductorsUp to 500kHz Switching Frequency±1.5% Reference Tolerance Over TemperatureLow-Battery Detector (LBI/LBO)8-Pin SO and µMAXPackages
______________Ordering Information
Ordering Information continued at end of data sheet.* Dice are tested at TA= +25°C only.Contact factory for availability.
MAX856–MAX859
3.3V/5V or Adjustable-Output,
Step-Up DC-DC ConvertersGND
OUT
LBILBO
REF
3/5
SHDN
MAX856
MAX858
SO/μMAXTOP VIEW
GND
OUT
LBILBO
REF
SHDN
MAX857
MAX859
SO/μMAX
__________________Pin ConfigurationMAX856
SHDN
3/5
REF
GND
OUT
INPUT
0.8V TO VOUT
1N5817
OUTPUT
5V AT 100mA
3.3V AT 125mA
LBO
68μF
47μH
LOW-BATTERY
DETECTOR OUTPUT
ON/OFF
3V/5V SELECT
LBILOW-BATTERY
DETECTOR
INPUT
__________Typical Operating Circuit19-0211; Rev 4; 5/96
PARTTEMP. RANGEPIN-PACKAGE
MAX856CSA0°C to +70°C8 SO
MAX856CUA0°C to +70°C8 µMAX
MAX856C/D0°C to +70°CDice*
MAX856ESA-40°C to +85°C8 SO
MAX856MJA-55°C to +125°C8 CERDIP†
MAX857CSA0°C to +70°C8 SO
MAX857CUA0°C to +70°C8 µMAX
MAX857C/D0°C to +70°CDice*
MAX857ESA-40°C to +85°C8 SO
MAX857MJA-55°C to +125°C8 CERDIP†
EVALUATION KIT
AVAILABLE
MAX856–MAX859
3.3V/5V or Adjustable-Output,
Step-Up DC-DC Converters
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS(Circuits of Figure 2, VIN= 2.5V, ILOAD= 0mA, 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.
Supply Voltage (OUT to GND) ...................................-0.3V, +7V
Switch Voltage (LX to GND) .......................................-0.3V, +7V—H—D—N–, LBO to GND....................................................-0.3V, +7V
LBI, REF, 3/–5–, FB to GND.........................-0.3V, (VOUT+ 0.3V)
Reference Current (IREF) ..................................................2.5mA
Continuous Power Dissipation (TA= +70°C)
SO (derate 5.88mW/°C above +70°C) .........................471mW
µMAX(derate 4.1mW/°C above +70°C) ......................330mW
CERDIP (derate 8.00mW/°C above +70°C) .................640mW
Reverse Battery Current (TA≤+45°C, Note 1).................750mA
Operating Temperature Ranges
MAX85_C_ _ ......................................................0°C to +70°C
MAX85_E_ _ ....................................................-40°C to +85°C
MAX85_MJA .................................................-55°C to +125°C
Junction Temperature .....................................................+150°C
Storage Temperature Range ............................-65°C to +160°C
Lead Temperature (soldering, 10sec) ............................+300°C
Note 1:Reverse battery current is measured from the Typical Operating Circuit’sbattery input terminal to GND when the battery is
connected backwards. A reverse current of 750mA will not exceed the SO or CERDIP package dissipation limits but, if left
for an extended time (more than ten minutes), may degrade performance.
LBO = 5V
ISINK= 2mA
With falling edge–5–= 3V, -20µA ≤REF load ≤250µA, CREF= 0.22µF
No REF load
MAX858/MAX859
ILOAD= 0mA, 3/–5–= 3V, LBI = 1.5V, VOUT= 3.47V,
(FB = 1.5V, MAX857/MAX859 only)
MAX856/MAX857—H—D—N–= 0V, 3/–5–= 3V, LBI = 1.5V, VOUT= 3.47V,
(FB = 1.5V, MAX857/MAX859 only)
2V ≤VIN≤3V
ILOAD= 0mA
Output set for 3.3V, measured at VINin Figure 2, R3 omitted.
CONDITIONS1LBO Output Leakage Current0.4LBO Output Voltage Low25LBI Input Hysteresis1.221.251.28LBI Input Threshold0.82.0Reference-Voltage Regulation1.231.251.27Reference Voltage
Shutdown Quiescent Current
(Note 2)60No Load Battery Current
4.805.05.202560Quiescent Supply Current in
3.3V Mode (Note 2)0.8Minimum Operating Voltage
Output Voltage0.81.8Minimum Start-Up
Supply Voltage
UNITSMINTYPMAXPARAMETERPeak Inductor Current Limit
MAX856, 3/–5–= 0V, 0mA ≤ILOAD≤100mA
MAX856, 3/–5–= 3V, 0mA ≤ILOAD≤150mA
MAX857, VOUT= 5V, 0mA ≤ILOAD≤100mA
MAX858, 3/–5–= 0V, 0mA ≤ILOAD≤25mA
MAX858, 3/–5–= 3V, 0mA ≤ILOAD≤35mA
MAX859, VOUT= 5V, 0mA ≤ILOAD≤25mA
MAX85_C
MAX85_E/M
MAX856–MAX859
3.3V/5V or Adjustable-Output,
Step-Up DC-DC ConvertersMAX858/MAX859
EFFICIENCY vs. OUTPUT CURRENT
VOUT = 3.3V
MAX856-01
LOAD CURRENT (mA)
EFFICIENCY (%)
VIN = 2.0V
VIN = 2.5V
VIN = 1.5V
MAX858/MAX859
EFFICIENCY vs. OUTPUT CURRENT
VOUT = 5V
MAX856-02
LOAD CURRENT (mA)
EFFICIENCY (%)
VIN = 2.5V
VIN = 3.3V
VIN = 1.5V
MAX856/MAX857
EFFICIENCY vs. OUTPUT CURRENT
VOUT = 5V
MAX856-03
LOAD CURRENT (mA)
EFFICIENCY (%)
VIN = 2.0V
VIN = 3.3V
VIN = 1.5V
MAX856/MAX857
EFFICIENCY vs. OUTPUT CURRENT
VOUT = 3.3V
MAX856-04
LOAD CURRENT (mA)
EFFICIENCY (%)
VIN = 2.0V
VIN = 2.5V
VIN = 1.5V
__________________________________________Typical Operating Characteristics(Circuits of Figure 2, TA= +25°C, unless otherwise noted.)
ELECTRICAL CHARACTERISTICS (continued)(Circuits of Figure 2, VIN= 2.5V, ILOAD= 0mA, TA= TMINto TMAX, unless otherwise noted. Typical values are at TA= +25°C.)
Note 2:Supply current from the 3.3V output is measured with an ammeter between the 3.3V output and OUT pin. This current
correlates directly with actual battery supply current, but is reduced in value according to the step-up ratio and efficiency.
VOUT= 3.47V to keep the internal switch open when measuring the current into the device.
Note 3:Minimum value is production tested. Maximum value is guaranteed by design and is not production tested.S—H—D—N–, 3/–5–Input Voltage Low0.4V—H—D—N–, 3/–5–Input Voltage High1.6V—H—D—N–, 3/–5–, FB, LBI Input CurrentLBI = 1.5V, FB = 1.5V, –S—H—D—N–= 0V or 3V, 3/–5–= 0V or 3V±100nA
FB VoltageMAX857/MAX8591.221.251.28V
Output Voltage RangeMAX857/MAX859, ILOAD= 0mA (Note 3)2.76.0V
MAX856–MAX859
3.3V/5V or Adjustable-Output,
Step-Up DC-DC Converters
_____________________________Typical Operating Characteristics (continued)(Circuits of Figure 2, TA= +25°C, unless otherwise noted.)
MAX856/MAX857
MINIMUM START-UP INPUT VOLTAGE
vs. LOAD CURRENT
MAX856-06
LOAD CURRENT (mA)
START-UP INPUT VOLTAGE (V)
VOUT = 3.3V
VOUT = 5V
MAX858/MAX859
MINIMUM START-UP INPUT VOLTAGE
vs. LOAD CURRENT
MAX856-07
LOAD CURRENT (mA)
START-UP INPUT VOLTAGE (V)0.9
VOUT = 5V
SHUTDOWN CURRENT
vs. INPUT VOLTAGE
MAX856-11
SHUTDOWN CURRENT (
INPUT VOLTAGE (V)
TA = +85°C
TA = +25°C
TA = -40°C
MAX858/MAX859
MAXIMUM OUTPUT CURRENT
vs. INPUT VOLTAGE
MAX856-12
LOAD CURRENT (mA)
INPUT VOLTAGE (V)
VOUT = 5.0V
VOUT = 3.3V
MAX856/MAX857
MAXIMUM OUTPUT CURRENT
vs. INPUT VOLTAGE
MAX856-13
LOAD CURRENT (mA)
INPUT VOLTAGE (V)
VOUT = 5.0V
VOUT = 3.3V
QUIESCENT CURRENT
vs. INPUT VOLTAGE
1.4MAX856-10
QUIESCENT CURRENT (mA)
INPUT VOLTAGE (V)
SEE NOTE 2
IN THE ELECTRICAL
CHARACTERISTICS
TA = +85°C
TA = -40°C
MAX858/MAX859
NO LOAD BATTERY CURRENT
vs. INPUT VOLTAGE
MAX856-09
QUIESCENT CURRENT (mA)
INPUT VOLTAGE (V)
INCLUDES ALL EXTERNAL
COMPONENT LEAKAGES.
CAPACITOR LEAKAGE
DOMINATES AT TA = +85°C.
CAPS ARE SPRAGUE 595D
TA = +85°C
TA = +25°C
TA = -40°C
MAX856/MAX857
NO LOAD BATTERY CURRENT
vs. INPUT VOLTAGE
MAX856-08
QUIESCENT CURRENT (
INPUT VOLTAGE (V)
TA = +85°C
TA = +25°C
TA = -40°C
INCLUDES ALL EXTERNAL
COMPONENT LEAKAGES.
CAPACITOR LEAKAGE
DOMINATES AT TA = +85°C.
CAPS ARE SPRAGUE 595 D
REFERENCE VOLTAGE vs. CURRENTMAX856-05
REFERENCE LOAD CURRENT (μA)
REF
LOAD REGULATION (mV)
100200150250
MAX856–MAX859
3.3V/5V or Adjustable-Output,
Step-Up DC-DC Converters
MAX856/MAX857
LINE-TRANSIENT RESPONSE (5V MODE)2ms/div
VOUT
50mV/div
VIN
MAX856/MAX857
LOAD-TRANSIENT RESPONSE (5V MODE)50μs/div
VOUT
50mV/div
0mA to 100mA
ILOAD
VIN = 2.5V
MAX858/MAX859 LOAD-TRANSIENT RESPONSE2ms/div
VOUT
50mV/div
0mA to 25mA
ILOAD0
VIN = 2.5V
MAX859 LINE-TRANSIENT RESPONSE1ms/div
VOUT
50mV/div
1V/div
VIN
MAX858/MAX859 START-UP DELAY (5V MODE)5ms/div
VOUT
2V/div
5V/div
VSHDN
VIN = 2.5V, ILOAD = 25mA
MAX856 START-UP DELAY (5V MODE)5ms/div
VOUT
2V/div
5V/div
VSHDN
VIN = 2.5V, ILOAD = 100mA
_____________________________Typical Operating Characteristics (continued)(Circuits of Figure 2, TA= +25°C, unless otherwise noted.)
