Datasheet

UNISONIC TECHNOLOGIES CO., LTD
L1803
Preliminary
LINEAR INTEGRATED CIRCUIT
1.5A ULTRA LOW DROPOUT
LINEAR REGULATOR WITH
PROGRAMMABLE
SOFT-START

DESCRIPTION
The UTC L1803 is a typical LDO that features a
user-programmable soft-start, very low dropout voltage as low as
0.15V at output current 1.5A, an enable input and a power-good
output.
The soft-start reduces inrush current of the load capacitors and
minimizes stress on the input power source during start-up. An
enable pin to further reduce power dissipation while shutdown. And
power-good output indicates the output voltage status.
The UTC L1803 is stable with any type of output capacitor of
2.2µF or more. A precision reference and feedback control deliver
2% accuracy over load, line, and operating temperature ranges.

FEATURES
* Low VIN and wide VIN range: 1.0V~5.5V
* Bias voltage (VVCC) range: 2.7V~5.5V
* Low VOUT range: 0.8V~3.3V
* 150mV dropout @1.5A, VVCC=5V
* 2% output Voltage
* Power-Good (PG) output
* Programmable soft-start provides linear voltage startup
* Stable with any output capacitor≥2.2µF

ORDERING INFORMATION
Ordering Number
L1803G-SH2-R
L1803G-K10-3030-R
Package
HSOP-8
DFN-10(3×3)
Packing
Tape Reel
Tape Reel
L1803G-SH2-R
(1)Packing Type
(1) R: Tape Reel
(2)Package Type
(2) SH2: HSOP-8, K10-3030: DFN-10(3×3)
(3)Green Package
(3) G: Halogen Free and Lead Free
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Copyright © 2015 Unisonic Technologies Co., Ltd
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L1803

Preliminary
LINEAR INTEGRATED CIRCUIT
MARKING
HSOP-8
DFN-10(3×3)

PIN CONFIGURATION

PIN DESCRIPTION
HSOP-8
1
2
3
4
5
6
7
8
-
PIN NO.
DFN-10(3×3)
1, 2
3
4
5
6
7
8
9
10
PIN NAME
IN
PG
VCC
EN
GND
SS
FB
OUT
NC
DESCRIPTION
The main power Input pin.
Power-good pin, open-drain output.
Bias input pin of the control circuitry
Enable pin.
Ground.
Soft-start pin.
Feedback pin.
Regulated output pin.
NO Connection.
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
Preliminary
LINEAR INTEGRATED CIRCUIT
BLOCK DIAGRAM
OUT
IN
EN
Gate
Driver
Current
Limit
Thermal
Shutdown
SS
VCC
+
0.8V
FB
PG
+
0.72V
GND
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Preliminary
LINEAR INTEGRATED CIRCUIT
ABSOLUTE MAXIMUM RATING
PARAMETER
SYMBOL
RATINGS
UNIT
Input Voltage Range
VIN, VVCC
-0.3~+6
V
Enable Voltage Range
VEN
-0.3~+6
V
Power-Good Voltage Range
VPG
-0.3~+6
V
Soft-Start Voltage Range
VSS
-0.3~+6
V
Feedback Voltage Range
VFB
-0.3~+6
V
Output Voltage Range
VOUT
-0.3~VIN +0.3
V
Maximum Output Current
IOUT
Internally Limited
Junction Temperature
TJ
-40~+150
°C
Storage Temperature
TSTG
-65~+150
°C
Note: Absolute maximum ratings are those values beyond which the device could be permanently damaged.
Absolute maximum ratings are stress ratings only and functional device operation is not implied.

RECOMMENDED OPERATING CONDITIONS
PARAMETER
SYMBOL
MIN
Input Voltage (Note)
VIN
1.0
Bias Voltage
VVCC
2.7
Output Current
IOUT
0
Operating Ambient Temperature
TA
-40
Note: At VIN =1V, the maximum load currents may be lower than 1.5A.

MAX
5.5
5.5
1.5
85
UNIT
V
V
A
°C
THERMAL RESISTANCES CHARACTERISTICS
PARAMETER
SYMBOL
HSOP-8
Junction to Ambient
θJA
DFN-10(3×3)
Note: The PCB area is 4 times larger than that of IC’s

TYP
RATINGS
150
72 (Note )
UNIT
°C/W
°C/W
ELECTRICAL CHARACTERISTICS
At VEN=1.1V, VIN=VOUT+0.5V, CVCC=0.1uF, CIN=COUT=10uF, IOUT=50mA, VVCC=5.0V, and TA=-40°C~+85°C, unless
otherwise noted. Typical values are at TA=+25°C.
PARAMETER
SYMBOL
TEST CONDITIONS
MIN
TYP
MAX
UNIT
Input Voltage Range
VIN
VOUT+VDO
5.5
V
Bias Pin Voltage Range (Note 2)
VVCC
2.7
5.5
V
Internal Reference (Adj.)
VREF
TA=+25°C
0.792
0.8
0.808
V
Output Voltage Range
VIN=5V, IOUT=1.5A
0.8
3.3
V
VOUT
3V≤VVCC≤5.5V,
-2
±0.5
2
%
Accuracy (Note 2)
50mA≤IOUT≤1.5A
∆VOUT / ∆VIN
VOUT (NOM)+0.5≤VIN, 5.5V
Line Regulation
0.02
%/V
/ VOUT
∆VOUT / VOUT
50mA≤IOUT≤1.5A
Load Regulation
0.08
%/V
/ ∆IOUT
IOUT=1.5A,
150
270
mV
VVCC-VOUT(NOM)≥3.25V
Dropout Voltage (Note 3)
VDO
IOUT=1.5A, VIN=VVCC
1.5
1.7
V
Current Limit
ICL
VOUT=80%xVOUT (NOM)
2
3
4
A
Short-Circuit Current
ISHORT
VOUT<0.2V
0.6
1.1
A
Bias Pin Current
IVCC
1
2
mA
Shutdown Supply Current (IGND)
ISHDN
VEN≤0.4V
70
100
µA
Feedback Pin Current
IFB
-1
0.1
1
µA
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Preliminary
LINEAR INTEGRATED CIRCUIT
ELECTRICAL CHARACTERISTICS (Cont.)
PARAMETER
SYMBOL
Power-Supply Rejection (VIN~VOUT)
PSRR
Power-Supply Rejection
(VVCC~VOUT)
Startup Time
TST
Soft-Start Charging Current
Enable Input High Level
Enable Input Low Level
Enable Pin Hysteresis
Enable Pin Current
PG Trip Threshold
PG Trip Hysteresis
ISS
VEN, HI
VEN, LO
VEN, HYS
IEN
VPG, TH
VPG, HYS
TEST CONDITIONS
1KHz, IOUT=1A, VIN=1.8V,
VOUT=1.5V
300KHz, IOUT=1A, VIN=1.8V,
VOUT=1.5V
1KHz, IOUT=1A, VIN=1.8V,
VOUT=1.5V
300KHz, IOUT=1A, VIN=1.8V,
VOUT=1.5V
RLOAD for IOUT=1.0A,
CSS =OPEN
VSS=0.4V
MIN
TYP
85
dB
30
dB
50
dB
30
dB
100
µS
440
nA
V
V
mV
µA
%VOUT
%VOUT
5.5
0.4
50
0.1
90
7
IPG=1mA (Sinking), VOUT<VPG,
TH
PG Leakage Current
IPG, LKG
VPG=5.25V, VOUT>VPG, TH
0.1
Shutdown, Temperature
+150
Increasing
Thermal Shutdown Temperature
TSD
Reset, Temperature Decreasing
+130
Notes: 1. VVCC should be higher or equal to VIN in this chip.
2. Tested at 0.8V; resistor tolerance is not taken into account.
3. Dropout is defined as the voltage from VIN to VOUT when VOUT is 3% below nominal.
PG Output Low Voltage
VPG, LO
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UNIT
60
1.1
0
VEN=5V
VOUT Decreasing
MAX
1
94
0.3
V
1
µA
°C
°C
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Preliminary
LINEAR INTEGRATED CIRCUIT
TYPICAL APPLICATION CIRCUIT
VOUT
R3
VIN
OUT
IN
VVCC
PG
C1
VCC
C3
UTC
L1803
EN
R1
C2
FB
R2
SS
GND
CSS
Table 1. Capacitor Values for Programming the Soft-Start Time (Note)
CSS
Open
270pF
560pF
2.7nF
5.6nF
Note: tSS (s) = 0.8 x CSS (F) / (4.4x10-7)
SOFT-START TIME
0.1ms
0.5ms
1ms
5ms
10ms
UTC assumes no responsibility for equipment failures that result from using products at values that
exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or
other parameters) listed in products specifications of any and all UTC products described or contained
herein. UTC products are not designed for use in life support appliances, devices or systems where
malfunction of these products can be reasonably expected to result in personal injury. Reproduction in
whole or in part is prohibited without the prior written consent of the copyright owner. The information
presented in this document does not form part of any quotation or contract, is believed to be accurate
and reliable and may be changed without notice.
UNISONIC TECHNOLOGIES CO., LTD
www.unisonic.com.tw
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