Microsemi
Linfini ty Microelectronics Di vi sion
11861 Western A venue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 1
Copyright 2000
Rev. 0.2a, 2000-11-20
WWW.
Microsemi
.
COM
LX8815
Dual Channel 1A Low Dropout Regulator
PRELIMINARY
A MICROSEMI COMPANY
The LX8815 is a dual channel
positive-voltage linear regulator. This
dual regulator has either one fixed
output coupled with an adjustable
output or two fixed outputs. Each
channel features low-dropout and high
accuracy.
The LX8815 provides designers
with a flexible power management
solution, minimal printed circuit board
area, and shorter design cycles.
Each channel can supply up to one
amp independently with a regulator
design optimized for system efficiency
by consuming minimal ground current
and directing quiescent current to the
load.
The LX8815 features on-chip
trimming of the internal
voltage reference enabling precise output
voltages, typically ±1% of it’s specified
value, while the BiP olar output transistor
has a low dropout voltage even at full
output current (VDO < 1.1V typ. @ 1A).
Thermal and Short Circuit Current
Protection are integrated on-chip and
operate independently for each regulator
output.
The LX8815 regulator is stable with a
low-value output capacitor, typically
3.3µF tantalum or 4.7µF ceramic on the
outputs, allowing designers flexibility in
external component selection.
Linfinity’s S-PAK power package
offers maximum power dissipation and
ease of assembly using surface mount
technology.
IMPORTANT: For the most current data, consult
MICROSEMI
’s website: http://www.microsemi.com
Two Independent Regulated
Outputs
Accurate Output Voltages
Max. Dropout of 1.1V at Rated
Current
Independent Thermal and
Current Limit Protection
Low Profile 5 Lead SMT Power
Package
Low Tolerance Line (0.2%) and
Load (0.4%) Regulation
Wide DC Supply Voltage of 4.0V
to 12.0V
Loop Stability Independent of
Output Capacitor Type
5V to 3.3V Linear Regulator
Low Voltage Logic Supplies
Active SCSI Terminators
Battery Charging Circuits
Instrumentation
PC Peripherals
BIAS 1.25V
V
REF
1
3
V
IN
GND
5
4
2
+
+
-
-
V
OUT1
V
OUT2
R
3
0.1
Ω
C
1
10
µ
FC
2
4.7
µ
F
R
1
R
2
C
3
4.7
µ
F
2
2
1
2125.1 RI
R
R
VADJOUT ×+
+×=
Note: Application circuit above using ceramic capacitors, C
1
requires R
3
(0.075 to 0.3
Ω
). For Tantalum capacitors: R
3
is not used
and C
1
, C
2
, and C
3
> 2
µ
F. R1 and R2 used with LX88xx-xx only.
Adjustable or Fixed
L
LX
X8
88
81
15
5
Microsemi
Linfini ty Microelectronics Di vi sion
11861 Western A venue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 2
Copyright 2000
Rev. 0.2a, 2000-11-20
WWW.
Microsemi
.
COM
LX8815
Dual Channel 1A Low Dropout Regulator
PRELIMINARY
A MICROSEMI COMPANY
TJ (°C) OUTPUT V1 OUTPUT V2 DF Plastic S-PAK
5-PIN
3.3V 2.5V LX8815-3325CDF
3.3V 1.8V LX8815-3318CDF
3.3V Adj LX8815-3300CDF
2.85V Adj LX8815-2800CDF
0 to 125
2.5V Adj LX8815-2500CDF
Note: Available in Tape & Reel.
Append the letter “T” to the part number. (i.e. LX8815-3325CDFT)
DF PACKAGE
THERMAL RESISTANCE-J UNCTION TO TAB, θJT
THERMAL RESISTANCE-J UNCTION TO AMBIENT, θJA 4.5°C/W
24.5°C/W
Junction Temperature Calculation: TJ = TA + (PD x θJA).
The θJA numbers are guidelines for the thermal performance of the device/pc-board
system. All o f the above assume no ambient airflow. θJA can vary from 20°C/W to >
40°C/W depending on mounting technique. (See Application Notes Section: Thermal
considerations)
DF P
ACKAGE
(Top View)
1
V
IN
ADJ
GND
V
OUT2
V
OUT1
2
3
4
5
TAB is GND
VIN Unregulated input voltage supply.
ADJ Adjust control pin for regulator 2
GND Common terminal for ground reference
VOUT1 Fixed voltage regulator output (Regulator #1)
VOUT2 Fixed or adjustable regulator output (Regulator #2)
Input Voltage (VBAT)..................................................................................................13.5V
Load Current (Internally Limited)...................................................................................1A
Power Dissipation ...................................................................................Internally Limited
Short-Circuit Prote c ti on ....................................................................................... Indefinite
Operating Junction Temperature................................................................................150°C
Lead Temperature (Soldering 180 seconds)...............................................................235°C
Note: Exceeding these ratings could cause damage to the device. All voltages are with respect to
Ground. Currents are positive into, negative out of specified terminal.
P
PA
AC
CK
KA
AG
GE
E
D
DA
AT
TA
A
Microsemi
Linfini ty Microelectronics Di vi sion
11861 Western A venue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page
3
Copyright 2000
Rev. 0.2a, 2000-11-20
WWW.
Microsemi
.
COM
LX8815
Dual Channel 1A Low Dropout Regulator
PRELIMINARY
A MICROSEMI COMPANY
Unless ot herwise specified, the following specifications apply over the o perating ambient temperature 0°C≤ TA≤ 125°C except where
otherwise noted and the following test conditions: VIN = 5V, IOUT = 10mA, C1 = 4.7µF (Tantalum), C2 = 4.7µF (Tantalum), and TJ = TA
25°C using low duty cycling methods.
LX8815-xx00
Parameter Symbol Test Conditions Min Typ Max
Units
FIXED OUTPUT
Output Voltage
• LX8815-3300
• LX8815-2800
• LX8815-2500
V1
VIN = 5V, IOUT = 5mA, TJ = 25°C
5mA < I1 < 1A, 4.50V < VIN < 10V
VIN = 5V, IOUT = 5mA, TJ = 25°C
5mA < I1 < 1A, 4.50V < VIN < 10V
VIN = 5V, IOUT = 5mA, TJ = 25°C
5mA < I1 < 1A, 4.50V < VIN < 10V
3.250
3.234
2.807
2.793
2.462
2.450
3.300
3.300
2.850
2.850
2.500
2.500
3.350
3.366
2.893
2.907
2.537
2.550
V
Line Regulation ∆V1(VIN) 4.75V < VIN < 10V, IOUT = 5mA 0.01 0.2 %V1
Load Regulation ∆V1(I1) 5mA < I1 < 1A, VIN = 4.75V 0.01 0.4 %V1
Dropout Voltage ∆V ILOAD = 1A, ∆V1 = -2% 1.1 1.25 V
Current Limit IOUT (MAX) (VIN – V1) = 5V 1.0 1.4 A
Minimum Load Current IL Note 1 0 2 mA
ADJUSTABLE OUTPUT
Reference Voltage VREF VIN = 5V, IOUT = 10mA, TJ = 25°C
5mA < I1 < 1A, 4.50V < VIN < 10V 1.238
1.231 1.250
1.250 1.262
1.269 V
Line Regulation ∆VREF(VIN) 4.75V < VIN < 10V, IOUT = 5mA 0.01 0.2 %V1
Load Regulation ∆VREF(I2) 5mA < I1 < 1A, VIN = 4.75V 0.01 0.4 %V1
Dropout Voltage ∆V VIN > 4.5V, ILOAD = 1A, ∆V1 = -1% 1.1 1.3 V
Current Limit IOUT (MAX) (VIN – V1) = 5V 1.0 1.4 A
Minimum Load Current IL Note 1 1 3 mA
Adjust Pin Bias Current IADJ 1 5
µA
ENTIRE RE GULATOR
Quiescent Current I Q VIN < 10V, I1 = 5mA, I2 = 5mA 1.8 5 mA
Ripple Rejection PSRR f=120Hz, VIN = 5V 60 75 dB
RMS Output Noise (% of VOUT) VOUT (RMS) 10Hz < f < 10kHz 0.003 %V1
Thermal Shutdown TJSD 140
°C
Note 1: Minimum load current is defined as the amount of output current required to maintain regulation.
E
EL
LE
EC
CT
TR
RI
IC
CA
AL
LS
S
Microsemi
Linfini ty Microelectronics Di vi sion
11861 Western A venue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page
4
Copyright 2000
Rev. 0.2a, 2000-11-20
WWW.
Microsemi
.
COM
LX8815
Dual Channel 1A Low Dropout Regulator
PRELIMINARY
A MICROSEMI COMPANY
Unless ot herwise specified, the following specifications apply over the o perating ambient temperature 0°C≤ TA≤ 125°C except where
otherwise noted and the following test conditions: VIN = 5V, IOUT = 10mA, C1 = 4.7µF (Tantalum), C2 = 4.7µF (Tantalum), and TJ = TA
25°C using low duty cycling methods.
LX8815-33xx
Parameter Symbol Test Conditions Min Typ Max
Units
FIXED OUTPUT 1
Output Voltage V1 VIN = 5V, IOUT = 5mA, TJ = 25°C
5mA < I1 < 1A, 4.50V < VIN < 10V 3.250
3.234 3.300
3.300 3.350
3.366 V
Line Regulation ∆V1(VIN) 4.75V < VIN < 10V, IOUT = 5mA 0.3 5.0 mV
Load Regulation ∆V1(I1) 5mA < I1 < 1A, VIN = 4.75V 0.8 10 mV
Dropout Voltage ∆V ILOAD = 1A, ∆V1 = -2% 1.1 1.25 V
Current Limit IOUT (MAX) (VIN – V1) 1.0 1.4 A
Minimum Load Current IL Note 1 0 2 mA
FIXED OUTPUT 2
Output Voltage
• LX8815-3325
• LX8815-3318
V1
VIN = 5V, IOUT = 5mA, TJ = 25°C
5mA < I1 < 1A, 4.50V < VIN < 10V
VIN = 5V, IOUT = 5mA, TJ = 25°C
5mA < I1 < 1A, 4.50V < VIN < 10V
2.462
2.450
1.773
1.764
2.50
2.50
1.80
1.80
2.537
2.550
1.827
1.36
V
Line Regulation ∆V1(VIN) 4.75V < VIN < 10V, IOUT = 5mA 0.02 0.15 %mV
Load Regulation ∆V1(I1) 5mA < I1 < 1A, VIN = 4.75V 0.04 0.3 %mV
Dropout Voltage ∆V VIN > 4.5V, ILOAD = 1A, ∆V1 = -1% 1.1 1.3 V
Current Limit IOUT (MAX) (VIN – V1) 1.0 1.4 A
Minimum Load Current IL Note 1 1 2 mA
ENTIRE RE GULATOR
Quiescent Current I Q VIN < 10V, I1 = 5mA, I2 = 5mA 1.8 7 mA
Ripple Rejection PSRR f=120Hz, VIN = 5V 60 75 dB
RMS Output Noise (% of VOUT) VOUT (RMS) 10Hz < f < 10kHz 0.003 %V1
Thermal Shutdown TJSD 140
°C
Note 1: Minimum load current is defined as the amount of output current required to maintain regulation.
E
EL
LE
EC
CT
TR
RI
IC
CA
AL
LS
S
Microsemi
Linfini ty Microelectronics Di vi sion
11861 Western A venue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 5
Copyright 2000
Rev. 0.2a, 2000-11-20
WWW.
Microsemi
.
COM
LX8815
Dual Channel 1A Low Dropout Regulator
PRELIMINARY
A MICROSEMI COMPANY
A
BK
FG
I
D
J
H
C
E
Note:
1. Dimensions do not include mold flash or protrusions;
these shall not exceed 0.155mm(.006”) on any side.
Lead dimension shall not include s ol der coverage.
MILLIMETERS INCHES
Dim MIN MAX MIN MAX
A 9.27 9.52 .365 .375
B 8.89 9.14 .350 .360
C 1.77 2.03 .070 .080
D 7.49 7.74 .295 .305
E 0.12 0.38 .005 .015
F 0.58 0.84 .023 .033
G 1.70 BSC 0.067 BSC
H 0.79 1.04 .031 .041
I 4.31 6.86 .170 .270
J 0.03 0.13 .001 .005
K 10.41 10.67 .410 .420
Preliminary Data – Information contained in this document is pre-production data and is proprietary to LinFinity. It
may not be mod ified in any w ay witho ut the e xpres s writ ten co nsent o f LinFinity. Product referred to herein is offere d
in sample form only and LinFinity reserves the right to change or discontinue this proposed product at any time.
M
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EC
CH
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AN
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CA
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