HIGH EFFICIENCY. 8187 Datasheet
LOW-DROPOUT/ 3.3 V REGULATOR . HIGH EFFICIENCY
|Total Page||8 Pages|
LOW-DROPOUT, 3.3 V REGULATOR
— HIGH EFFICIENCY
Designed specifically to meet the requirement for extended opera-
tion of battery-powered equipment such as cordless and cellular
telephones, the A8187SLT voltage regulator offers the reduced dropout
voltage and quiescent current essential for maximum battery life.
Applicable also to palmtop computers and personal data assistants, the
device delivers a regulated, continuous 3.3 V output at up to 75 mA
under normal operating conditions, or to 150 mA (transient) under
A PMOS pass element provides a typical dropout voltage of only
85 mV at 60 mA of load current. The low dropout voltage permits
deeper battery discharge before output regulation is lost. Furthermore,
quiescent current does not increase as the dropout voltage is ap-
proached, an ideal feature in standby/resume power systems where
data integrity is crucial. Regulator accuracy and excellent temperature
characteristics are provided by a bandgap reference.
This device is supplied in a small-outline plastic transistor package
(SOT-89/TO-243AA) for surface-mount applications. The A8187SLT is
rated for operation over a temperature range of -20°C to +85°C. A
similar device with an ENABLE input for control over sequential power
up, standby, or power down is the A8186SLU.
ONT EFERABSOLUTE MAXIMUM RATINGS
C RInput Voltage, VI . . . . . . . . . . . . . . 10 V
Output Current, IO . . . . . . . . . 150 mA*
IS ROperating Temperature Range,
D OTA . . . . . . . . . . . . . -20°C to +85°C
FJunction Temperature, TJ . . . +150°C†
Storage Temperature Range,
—TS . . . . . . . . . . . . -40°C to +150°C
FEATURES AND BENEFITS
I High Efficiency Provides Extended Battery Life
I 85 mV Typical Dropout Voltage at IO = 60 mA
I 45 µA Typical Quiescent Current at VI = 6 V
I Up to 150 mA Output Current
I Internal Thermal Protection
I Surface-Mount Package
I Cordless and Cellular Telephones
* Output current rating is limited by input voltage,
duty cycle, and ambient temperature. Under
any set of conditions, do not exceed a junction
temperature of +150°C. See next page.
I Personal Data Assistants
I Personal Communicators
I Palmtop Computers
† Fault conditions that produce excessive junction
temperature will activate device thermal
shutdown circuitry. These conditions can be
tolerated but should be avoided.
Always order by complete part number: A8187SLT .
3.3 V REGULATOR
FUNCTIONAL BLOCK DIAGRAM
MAXIMUM ALLOWABLE OUTPUT CURRENT with device mounted on 2.24" x 2.24"
(56.9 mm x 56.9 mm) solder-coated copper-clad board in still air.
Maximum Allowable Output Current in Milliamperes with VI = 8 V, TJ = 150°C, Period ≤10 s*
dc (Duty Cycle)
100 115 125 145 150 150 150 150
90 100 115 135 150 150 150 150
90 110 130 150 150 150
85 105 130 150 150
* IO = (TJ - TA)/([VI - VO] RθJA • dc) = (150 - TA)/(4.7 • 258 • dc)
Output current rating can be increased (to 150 mA maximum) by heat sinking or reducing the input voltage. Conditions that produce excessive
junction temperature will activate device thermal shutdown circuitry. These conditions can be tolerated but should be avoided.
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
Copyright © 1995, 2000 Allegro MicroSystems, Inc.
|Features||Datasheet pdf 8187 LOW-DROPOUT, 3.3 V REGULATOR — H IGH EFFICIENCY Designed specifically to meet the requirement for extended oper ation of battery-powered equipment such as cordless and cellular telephones, t he A8187SLT voltage regulator offers th e reduced dropout voltage and quiescent current essential for maximum battery life. Applicable also to palmtop comput ers and personal data assistants, the d evice delivers a regulated, continuous 3.3 V output at up to 75 mA under norma l operating conditions, or to 150 mA (t ransient) under worst-case conditions. A PMOS pass element provides a typical dropout voltage of only 85 mV at 60 mA of load current. The low dropout voltag e permits deeper battery discharge befo re output regulation is lost. Furthermo re, quiescent current does not increase as the dropout voltage is approached, an ideal feature in standby/resume powe r systems where data integrity is cruci al. Regulator accuracy and excellent te mperature characteristics are provided by a bandgap reference. Th.|
|Keywords||8187, datasheet, pdf, Allegro MicroSystems, LOW-DROPOUT/, 3.3, V, REGULATOR, ., HIGH, EFFICIENCY, 187, 87, 7, 818, 81, 8, Equivalent, stock, pinout, distributor, price, schematic, inventory, databook, Electronic, Components, Parameters, parts, cross reference, chip, Semiconductor, circuit, Electric, manual, substitute|