ams Datasheet Page 1
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AS1374
Dual 200mA, Low-Noise, High-PSRR,
Low Dropout Regulator
The AS1374 is a low-noise, low-dropout linear regulator with
two separated outputs. Designed to deliver 200mA continuous
output current at each output pin, the LDOs can achieve a low
120mV dropout for 200mA load current and are designed and
optimized to work with low-cost, small-capacitance ceramic
capacitors.
An integrated P-channel MOSFET pass transistor allows the
devices to maintain extremely low quiescent current (30μA).
The AS1374 uses an advanced architecture to achieve ultra-low
output voltage noise of 20μVRMS and a power-supply
rejection-ratio of better than 85dB (@ 1kHz).
Two active-High enable pins allows to switch on or off each
output independently from each other.
The AS1374 requires only 1μF output capacitor for stability at
any load.
The device is available in a 6-bump WLCSP package.
Ordering Information and Content Guide appear at end of
datasheet.
Key Benefits & Features
The benefits and features of AS1374, Dual 200mA, Low-Noise,
High-PSRR, Low Dropout Regulator are listed below:
Figure 1:
Added Value of Using AS1374
Benefits Features
•Ideal for battery-powered applications
•Input voltage from 2.0V to 5.5V
•Low quiescent current of 30μA
•Low dropout of 120mV at 200mA load
•Supports a variety of end applications
•Output voltage from 1.2V to 3.6V
•Guaranteed output current of 200mA
•Pull-down option in shutdown (factory set)
•Overtemperature and overcurrent protection
and shutdown
•Integrated temperature and output power
monitoring
•Cost-effective, small PCB area needed •Small external components needed
•Small 6-balls WLCSP package
General Description
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AS1374 − General Description
Applications
The devices are ideal for mobile phones, wireless phones, PDAs,
handheld computers, mobile phone base stations, Bluetooth
portable radios and accessories, wireless LANs, digital cameras,
personal audio devices, and any other portable,
battery-powered application.
Figure 2:
A1374 Typical Application Circuit
AS1374
VDD
EN1
OUT1
COUT1
1uF
CIN
1uF
Output1
1.2V to 3.6V
GND
ON
OFF
Input
2.0V to 5.5V
EN2
ON
OFF
OUT2
COUT2
1uF
Output2
1.2V to 3.6V
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AS1374 − General Description
Block Diagram
The functional blocks of this device are shown below:
Figure 3:
A1374 Block Diagram
Thermal
Protection
Enable
Logic CH2
Overcurrent
Protection CH1
AS1374
EN1
VDD
OUT1
GND
OUT2
Enable
Logic CH1
Common
Logic
EN2
Bandgap Trimmable
Reference Overcurrent
Protection CH2
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AS1374 − Pin Assignment
Figure 4:
Pin Diagram
Figure 5:
Pin Descriptions
Pin Number Pin Name Description
A1 OUT 2 Regulated Output Voltage 2. Bypass this pin with a capacitor to GND.
See Application Information for capacitor selection.
A2 VDD Input Supply
A3 OUT 1 Regulated Output Voltage 1. Bypass this pin with a capacitor to GND.
See Application Information for capacitor selection.
B1 EN 2 Enable 2. Pull this pin to logic low to disable Regulated Output 2
voltage.
B2 GND Ground
B3 EN 1 Enable 1. Pull this pin to logic low to disable Regulated Output 1
voltage.
Pin Assignment
A1
OUT2
Pin A1
indicator
A2
VDD
B1
EN2
B2
GND
A3
OUT1
B3
EN1
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AS1374 − Absolute Maximum Ratings
Stresses beyond those listed in 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 Electrical
Characteristics is not implied. Exposure to absolute maximum
rating conditions for extended periods may affect device
reliability.
Figure 6:
Absolute Maximum Ratings
Parameter Min Max Units Comments
Electrical Parameters
VDD to GND -0.3 7 V
All other pins to GND -0.3 VDD + 0.3 V
Output short-circuit duration Infinite
Input current (latch-up immunity) -100 100 mA JEDEC 78
Electrostatic Discharge
Electrostatic discharge HBM ±2 kV MIL 883 E method 3015
Temperature Ranges and Storage Conditions
Thermal resistance ΘJA 201.7 ºC/W
Junction-to-ambient thermal
resistance is very dependent on
application and board-layout. In
situations where high maximum
power dissipation exists, special
attention must be paid to thermal
dissipation during board design.
Junction temperature 125 ºC
Storage temperature range -55 150 ºC
Package body temperature 260 ºC
The reflow peak soldering
temperature (body temperature)
specified is in accordance with
IPC/JEDEC J-STD-020“Moisture/Reflow
Sensitivity Classification for
Non-Hermetic Solid State Surface
Mount Devices”.
Relative humidity non-condensing 5 85 %
Moisture sensitivity level 1 Maximum floor life time of Unlimited
Absolute Maximum Ratings
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AS1374 − Electrical Characteristics
V
IN
= V
OUT
+ 0.5V, V
OUT
= 2.85V, C
IN
= C
OUT
= 1μF, Typical values
are at T
AMB
= 25ºC (unless otherwise specified). All limits are
guaranteed. The parameters with min and max values are
guaranteed with production tests or SQC (Statistical Quality
Control) methods.
Figure 7:
Electrical Characteristics
Symbol Parameter Condition Min Typ Max Unit
T
AMB
Operating Temperature
Range -40 85 °C
V
IN
Input Range 2 5.5 V
∆V
OUT
Output Voltage Accuracy
I
OUT
= 1mA, T
AMB
= 25ºC -1 +1
%
I
OUT
= 100μA to 200mA,
T
AMB
= 25ºC -1.5 +1.5
I
OUT
= 100μA to 200mA -2.5 +2.5
I
OUT
Maximum Output
Current Each channel 200 mA
I
GND
Ground Current
One channel on, I
OUT
= 50μA 25 50 μA
One channel on, I
OUT
= 200mA 30 55 μA
I
LIMIT
Current Limit OUT = short 210 300 400 mA
Dropout Voltage
(1)
2V ≤ V
OUT
< 2.5V,
I
OUT
= 100mA 80 150 mV
IQ Quiescent Current
Both channels on,
I
OUT
= 0.05mA 30 90
μA
Both channels ON,
V
IN
= V
OUTNOM
- 0.1V,
I
OUT
= 0mA
50
V
LNR
Line Regulation VI
N
= (V
OUT
+0.5V) to 5.5V,
I
OUT
= 1mA 0.02 %/V
V
LDR
Load Regulation I
OUT
= 1 to 200mA 0.00
05 %/mA
I
SHDN
Shutdown Current OUT 1 and OUT 2 disable 0.01 2 μA
PSRR Ripple Rejection
f = 1kHz, I
OUT
= 10mA 85
dB
f = 10kHz, I
OUT
= 10mA 65
f = 100kHz, I
OUT
= 10mA 50
Electrical Characteristics
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AS1374 − Electrical Characteristics
Note(s):
1. Dropout is defined as VIN - VOUT when VOUT is 100mV below the value of VOUT for VIN = VOUT + 0.5V.
2. Time needed for VOUT to reach 90% of final value.
Output Noise Voltage
(RMS)
f = 100Hz to 100kHz,
I
LOAD
= 20mA 20 μV
Enable
Enable Input Bias Current 0.01 μA
Enable Exit Delay
(2)
Both channels initially OFF 150
μs
One channel initially OFF 200
Enable Logic Low Level 0.4 V
Enable Logic High Level 1.4 V
Thermal Protection
TSHDN Thermal Shutdown
Temperature 160 ºC
∆TSHDN Thermal Shutdown
Hysteresis 15 ºC
C
OUT
Output Capacitor
Load Capacitor Range 0.47 10 μF
Maximum ESR Load 500 mΩ
Symbol Parameter Condition Min Typ Max Unit
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AS1374 − Typical Operating Characteristics
V
IN
= V
OUT
+ 0.5V, V
OUT
= 2.85V, C
IN
= C
OUT
= 1μF,
T
AMB
= 25°C (unless otherwise specified).
Figure 8:
Output Voltage vs. Temperature
Figure 9:
Output Voltage vs. Input Voltage
Typical Operating
Characteristics
2.82
2.83
2.84
2.85
2.86
2.87
2.88
-45 -30 -15 0 15 30 45 60 75 90
Output Voltage (V )
Temperature (°C)
CH1
CH2
2.82
2.83
2.84
2.85
2.86
2.87
2.88
3.35 3.85 4.35 4.85 5.35
Output Voltage (V)
Input Voltage (V)
Iloa d = 1mA
Iload = 10 mA
Iload = 10 0mA
Iload = 20 0mA
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AS1374 − Typical Operating Characteristics
Figure 10:
Output Voltage vs. Load Current
Figure 11:
Output Voltage vs. Input Voltage - Dropout
2.8
2.81
2.82
2.83
2.84
2.85
2.86
2.87
2.88
0 25 50 75 100 125 150 175 200
Output voltage (V)
Load Current (mA)
-40°C
+25°C
+85°C
2.72
2.74
2.76
2.78
2.8
2.82
2.84
2.86
2.75 2.8 2.85 2.9 2.95 3 3.05
Output Voltage (V)
Input Voltage (V)
Iload = 100mA
Iload = 200mA
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AS1374 − Typical Operating Characteristics
Figure 12:
Dropout Voltage vs. Load Current
Figure 13:
PSRR vs. Frequency
0
25
50
75
100
125
150
25 50 75 100 125 150 175 200
Dropout Voltage (V )
Load Current (mA)
-40°C
+25°C
+85°C
20
30
40
50
60
70
80
90
100
100 1000 10000 100000
PSRR (dB)
Frequency (Hz)
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AS1374 − Typical Operating Characteristics
Figure 14:
Ground Pin Current vs. Load Current
Figure 15:
Ground Pin Current vs. Temperature
23
24
25
26
27
28
29
30
31
32
33
0 25 50 75 100 125 150 175 200
Ground Pin Current (µA )
Load Current (mA)
-40°C
+25°C
+85°C
25
26
27
28
29
30
-45 -30 -15 0 15 30 45 60 75 90
Ground Pin Current (µA )
Temperature (°C)
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AS1374 − Typical Operating Characteristics
Figure 16:
Ground Pin Current vs. Input Voltage; One Channel On, No
Load
Figure 17:
Ground Pin Current vs. Input Voltage; One Channel On,
I
LOAD
= 200mA
0
10
20
30
40
50
60
012345
Ground Pin Current (µ A)
Input Voltage (V)
-40°C
+25°C
+85°C
0
10
20
30
40
50
60
3.35 3.85 4.35 4.85 5.35
Ground Pin Current (µA )
Input Voltage (V)
-40°C
+25°C
+85°C
ams Datasheet Page 13
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AS1374 − Typical Operating Characteristics
Figure 18:
Ground Pin Current vs. Input Voltage; Both Channels on, No
Load
Figure 19:
Ground Pin Current vs. Input Voltage; Both Channels On,
I
LOAD
= 200mA
0
10
20
30
40
50
60
70
80
90
100
012345
Ground Pin Current (µ A)
Input Voltage (V)
-40°C
+25°C
+85°C
0
10
20
30
40
50
60
70
80
90
100
3.35 3.85 4.35 4.85 5.35
Ground Pin Current (µ A)
Input Voltage (V)
-40°C
+25°C
+85°C
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AS1374 − Typical Operating Characteristics
Figure 20:
Shutdown Current vs. Input Voltage
Figure 21:
Load Regulation vs. Temperature
0
10
20
30
40
50
60
0.51.52.53.54.55.5
Shutdown C urrent (nA)
Input Voltage (V)
-40°C
+25°C
+85°C
-0.0012
-0.001
-0.0008
-0.0006
-0.0004
-0.0002
0
-45 -30 -15 0 15 30 45 60 75 90
Load Regulation (% / mA)
Temperature (°C)
CH1
CH2
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AS1374 − Typical Operating Characteristics
Figure 22:
Line Regulation vs. Load Current
Figure 23:
Line Regulation vs. Temperature
-0.2
-0.15
-0.1
-0.05
0
0.05
0.1
0.15
0.2
0 25 50 75 100 125 150 175 200
Line Regulation (% / V)
Load Current (mA)
-40°C
+25°C
+85°C
-0.2
-0.15
-0.1
-0.05
0
0.05
0.1
0.15
0.2
-45 -30 -15 0 15 30 45 60 75 90
Line Regulation (% / V)
Temperature (°C)
Iloa d = 1mA
Iload = 10 mA
Iload = 10 0mA
Iload = 20 0mA
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AS1374 − Typical Operating Characteristics
Figure 24:
Load Transient Response, Crosstalk, Between CH1 and CH2,
I
OUT
= 200mA
Figure 25:
Load Transient Response Near Dropout,
I
OUT
= 200mA
Vout1
Vout2
Iout1
20us/div
10mV/div
10mV/div
100mA/div
Vout1
Iout1
20us/div
20mV/div
100mA/div
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AS1374 − Detailed Description
Figure 3 shows the block diagram of the AS1374. It identifies
the basics of a series linear regulator employing a P-Channel
MOSFET as the control element. A stable voltage reference (REF
in Figure 3) is compared with an attenuated sample of the
output voltage. Any difference between the two voltages
(reference and sample) creates an output from the error
amplifier that drives the series control element to reduce the
difference to a minimum. The error amplifier incorporates
additional buffering to drive the relatively large gate
capacitance of the series pass P-Channel MOSFET, when
additional drive current is required under transient conditions.
Input supply variations are absorbed by the series element, and
output voltage variations with loading are absorbed by the low
output impedance of the regulator.
Output Voltage
The AS1374 deliver preset output voltages from 1.2V to 3.6V, in
50mV increments (see Ordering Information).
Enable
The AS1374 feature an active high enable mode to shutdown
each output independently. Driving EN 1 low disables Output
1, driving EN 2 low disables Output 2. The disabled Output
enters a high-impedance state.
Current Limit
The AS1374 include a current limiting circuitry to monitor and
control the P-channel MOSFET pass transistor’s gate voltage,
thus limiting the device output current to 300mA.
Note(s): See Figure 7 for the recommended min and max
current limits. The output can be shorted to ground indefinitely
without causing damage to the device.
Thermal Protection
Integrated thermal protection circuitry limits total power
dissipation in the AS1374. When the junction temperature (T
J
)
exceeds 160ºC, the thermal sensor signals the shutdown logic,
turning off the P-channel MOSFET pass transistor and allowing
the device to cool down. The thermal sensor turns the pass
transistor on again after the device’s junction temperature
drops by 15ºC, resulting in a pulsed output during continuous
thermal-overload conditions.
Note(s): Thermal protection is designed to protect the devices
in the event of fault conditions. For continuous operation, do
not exceed the absolute maximum junction temperature rating
of 150ºC.
Detailed Description
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AS1374 − Application Information
Dropout Voltage
Dropout is the input to output voltage difference, below which
the linear regulator ceases to regulate. At this point, the output
voltage change follows the input voltage change. Dropout
voltage may be measured at different load currents, but is
usually specified at maximum output. As a result, the MOSFET
maximum series resistance over temperature is obtained. More
generally:
V
DROPOUT
= I
LOAD
x R
SERIES
Dropout is probably the most important specification when the
regulator is used in a battery application. The dropout
performance of the regulator defines the useful “end of life” of
the battery before replacement or re-charge is required.
Figure 30:
Graphical Representation of Dropout Voltage
Figure 30 shows the variation of V
OUT
as V
IN
is varied for a
certain load current. The practical value of dropout is the
differential voltage (V
OUT
- V
IN
) measured at the point where
the LDO output voltage has fallen by 100mV below the nominal,
fully regulated output value. The nominal regulated output
voltage of the LDO is that obtained when there is 500mV (or
greater) input-output voltage differential.
Application Information
(EQ1)
VOUT
VIN
VIN
VIN
VOUT
VOUT
VIN ≥ VOUT + 0.5V
100mV
Dropout
Voltage
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AS1374 − Application Information
Efficiency
Low quiescent current and low input-output voltage
differential are important in battery applications amongst
others, as the regulator efficiency is directly related to
quiescent current and dropout voltage. Efficiency is given by:
Efficiency = %
Where:
IQ = Quiescent current of LDO
Power Dissipation
Maximum power dissipation (PD) of the LDO is the sum of the
power dissipated by the internal series MOSFET and the
quiescent current required to bias the internal voltage
reference and the internal error amplifier, and is calculated as:
Watts
Internal power dissipation as a result of the bias current for the
internal voltage reference and the error amplifier is calculated
as:
Watts
Total LDO power dissipation is calculated as:
Watts
(EQ2)
V
LOAD
I
LOAD
×
V
IN
I
Q
I
LOAD
+()
-------------------------------------------100×
(EQ3)
PD MAX()
Seriespass()ILOAD MAX()
=V
IN MAX()
VOUT MIN()
–()
(EQ4)
PD MAX()
Bias()VIN MAX()
IQ
=
(EQ5)
PD MAX()
Total()PD MAX()
Seriespass()PD MAX()
+Bias()=
Page 22 ams Datasheet
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AS1374 − Application Information
Junction Temperature
Under all operating conditions, the maximum junction
temperature should not be allowed to exceed 125°C (unless
otherwise specified in the datasheet). Limiting the maximum
junction temperature requires knowledge of the heat path from
junction to case (θ
JC
°C/W fixed by the IC manufacturer), and
adjustment of the case to ambient heat path (θ
CA
°C/W) by
manipulation of the PCB copper area adjacent to the IC position.
Figure 31:
Steady State Heat Flow Equivalent Circuit
Total Thermal Path Resistance:
R
θ
JA = R
θ
JC + R
θ
CS + R
θ
SA
Junction Temperature (T
J
ºC) is determined by:
T
J
= (PD
(MAX)
x R
θ
JA) + T
AMB
ºC
Junction
TJ
Package
TC
PCB
TS
Ambient
TA
RθJC RθCS RθSA
RθJA
(EQ6)
(EQ7)
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AS1374 − Application Information
Explanation of Steady State Specifications
Line Regulation
Li ne regu la tion is d efin ed as t he ch ange in o ut put vo ltag e wh en
the input (or line) voltage is changed by a known quantity. It is
a measure of the regulator’s ability to maintain a constant
output voltage when the input voltage changes. Line
regulation is a measure of the DC open loop gain of the error
amplifier. More generally:
Line Regulation = and is a pure number
In practise, line regulation is referred to the regulator output
voltage in terms of % / V
OUT
. This is particularly useful when the
same regulator is available with numerous output voltage trim
options.
Line Regulation = % / V
Load Regulation
Load regulation is defined as the change of the output voltage
when the load current is changed by a known quantity. It is a
measure of the regulator’s ability to maintain a constant output
voltage when the load changes. Load regulation is a measure
of the DC closed loop output resistance of the regulator. More
generally:
Load Regulation = and is units of Ohms (Ω)
In practise, load regulation is referred to the regulator output
voltage in terms of % / mA. This is particularly useful when the
same regulator is available with numerous output voltage trim
options.
Load Regulation = % / mA
Setting Accuracy
Accuracy of the final output voltage is determined by the
accuracy of the ratio of R1 and R2, the reference accuracy and
the input offset voltage of the error amplifier. When the
regulator is supplied pre-trimmed, the output voltage accuracy
is fully defined in the output voltage specification.
When the regulator has a SET terminal, the output voltage may
be adjusted externally. In this case, the tolerance of the external
resistor network must be incorporated into the final accuracy
calculation. Generally:
The reference tolerance is given both at 25°C and over the full
operating temperature range.
(EQ8)
ΔV
OUT
ΔV
IN
------------------
(EQ9)
ΔV
OUT
ΔV
IN
------------------ 100
V
OUT
--------------
×
(EQ10)
ΔV
OUT
ΔI
OUT
------------------
(EQ11)
ΔV
OUT
ΔI
OUT
------------------ 100
V
OUT
--------------
×
(EQ12)
V
OUT
V
SET
ΔV
SET
±()1R1 ΔR1±
R2 ΔR2±
----------------------
+
=
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AS1374 − Application Information
Total Accuracy
Away from dropout, total steady state accuracy is the sum of
setting accuracy, load regulation and line regulation. Generally:
Total % Accuracy = Setting % Accuracy + Load Regulation % +
Line Regulation %
Explanation of Dynamic Specifications
Power Supply Rejection Ratio (PSRR)
Known also as Ripple Rejection, this specification measures the
ability of the regulator to reject noise and ripple beyond DC.
PSRR is a summation of the individual rejections of the error
amplifier, reference and AC leakage through the series pass
transistor. The specification, in the form of a typical attenuation
plot with respect to frequency, shows up the gain bandwidth
compromises forced upon the designer in low quiescent
current conditions. Generally:
PSRR = dB using lower case to indicate AC values
Power supply rejection ratio is fixed by the internal design of
the regulator. Additional rejection must be provided externally.
The AS1374 is designed to deliver low noise and high PSRR, with
low quiescent currents in battery-powered systems. The
power-supply rejection is 85dB at 1kHz and 50dB at 100kHz.
When operating from sources other than batteries, improved
supply-noise rejection and transient response are achieved by
increasing the values of the input and output capacitors.
Additional passive LC filtering at the input can provide
enhanced rejection at high frequencies.
Output Capacitor ESR
The series regulator is a negative feedback amplifier, and as
such is conditionally stable. The ESR of the output capacitor is
usually used to cancel one of the open loop poles of the error
amplifier in order to produce a single pole response. Excessive
ESR values may actually cause instability by excessive changes
to the closed loop unity gain frequency crossover point. The
range of ESR values for stability is usually shown either by a plot
of stable ESR versus load current, or a maximum value in the
datasheet.
Some ceramic capacitors exhibit large capacitance and ESR
variations with variations in temperature. Z5U and Y5V
capacitors may be required to ensure stability at temperatures
below T
AMB
= -10°C. With X7R or X5R capacitors, a 1μF capacitor
should be sufficient at all operating temperatures.
Larger output capacitor values (10μF) help to reduce noise and
improve load transient-response, stability and power-supply
rejection.
(EQ13)
(EQ14)
20LogδV
OUT
δV
IN
------------------
δ
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AS1374 − Application Information
Input Capacitor
An input capacitor at V
IN
is required for stability. It is
recommended that a 1.0μF capacitor be connected between
the AS1369 power supply input pin V
IN
and ground
(capacitance value may be increased without limit subject to
ESR limits). This capacitor must be located at a distance of not
more than 1cm from the V
IN
pin and returned to a clean analog
ground. Any good quality ceramic, tantalum, or film capacitor
may be used at the input.
Noise
The regulator output is a DC voltage with noise superimposed
on the output. The noise comes from three sources; the
reference, the error amplifier input stage, and the output
voltage setting resistors. Noise is a random fluctuation and if
not minimized in some applications, will produce system
problems.
Transient Response
The series regulator is a negative feedback system, and
therefore any change at the output will take a finite time to be
corrected by the error loop. This “propagation time” is related
to the bandwidth of the error loop. The initial response to an
output transient comes from the output capacitance, and
during this time, ESR is the dominant mechanism causing
voltage transients at the output. More generally:
Units are Volts, Amps, Ohms.
Thus an initial +50mA change of output current will produce a
-12mV transient when the ESR=240mΩ. Do remember to keep
the ESR within stability recommendations when reducing ESR
by adding multiple parallel output capacitors.
After the initial ESR transient, there follows a voltage droop
during the time that the LDO feedback loop takes to respond
to the output change. This drift is approx. linear in time and
sums with the ESR contribution to make a total transient
variation at the output of:
Units are Volts, Seconds, Farads, Ohms.
Where:
C
LOAD
is output capacitor
T= Propagation Delay of the LDO
This shows why it is convenient to increase the output capacitor
value for a better support for fast load changes. Of course the
formula holds for t < “propagation time”, so that a faster LDO
needs a smaller cap at the load to achieve a similar transient
response.
(EQ15)
δV
TRANSIENT
δI
OUTPUT
R
ESR
×=
(EQ16)
δV
TRANSIENT
δI
OUTPUT
R
ESR
T
C
LOAD
------------------
+
×=
Page 26 ams Datasheet
Document Feedback [v2-00] 2016-Jun-22
AS1374 − Application Information
For instance 50mA load current step produces 50mV output
drop if the LDO response is 1μs and the load cap is 1μF.
There is also a steady state error caused by the finite output
impedance of the regulator. This is derived from the load
regulation specification discussed above.
Turn On Time
This specification defines the time taken for the LDO to awake
from shutdown. The time is measured from the release of the
enable pin to the time that the output voltage is within 5% of
the final value. It assumes that the voltage at VIN is stable and
within the regulator min and max limits. Shutdown reduces the
quiescent current to very low, mostly leakage values (<1μA).
Thermal Protection
To prevent operation under extreme fault conditions, such as a
permanent short circuit at the output, thermal protection is
built into the device. Die temperature is measured, and when a
160°C threshold is reached, the device enters shutdown. When
the die cools sufficiently, the device will restart (assuming input
voltage exists and the device is enabled). Hysteresis of 15°C
prevents low frequency oscillation between start-up and
shutdown around the temperature threshold.
ams Datasheet Page 29
[v2-00] 2016-Jun-22 Document Feedback
AS1374 − Ordering & Contact Information
The devices are available as the standard products shown in
Figure 35.
Figure 35:
Ordering Information
Note(s):
1. On request
2. Non-standard devices from 1.2V to 3.6V are available in 50mV steps. For more information and inquiries contact www.ams.com/contact
Ordering Code Marking Package Output
Voltage 1 Output
Voltage 2 Delivery
Form Delivery
Quantity
AS1374-BWLT-285
(1)
ASSH 6-bump WLCSP 2.85V 2.85V Tape & Reel 10k pcs/reel
AS1374-BWLT1833 ASSJ 6-bump WLCSP 1.8V 3.3V Tape & Reel 10k pcs/reel
AS1374-BWLT1818 ASSP 6-bump WLCSP 1.8V 1.8V Tape & Reel 10k pcs/reel
AS1374-BWLT1218 ASSK 6-bump WLCSP 1.2V 1.8V Tape & Reel 10k pcs/reel
AS1374-BWLT1214 ASSY 6-bump WLCSP 1.2V 1.4V Tape & Reel 10k pcs/reel
AS1374-BWLT18285 ASSZ 6-bump WLCSP 1.8V 2.85V Tape & Reel 10k pcs/reel
AS1374-BWLT1212 ASSW 6-bump WLCSP 1.2V 1.2V Tape & Reel 10k pcs/reel
AS1374-BWLT1827 ASTB 6-bump WLCSP 1.8V 2.7V Tape & Reel 10k pcs/reel
AS1374-BWLT1533
(1)
ASTF 6-bump WLCSP 1.5V 3.3V Tape & Reel 10k pcs/reel
AS1374-BWLT1820
(1)
ASTG 6-bump WLCSP 1.8V 2.0V Tape & Reel 10k pcs/reel
AS1374-BWLT1821
(1)
ASTH 6-bump WLCSP 1.8V 2.1V Tape & Reel 10k pcs/reel
AS1374-BWLT2533
(1)
ASTI 6-bump WLCSP 2.5V 3.3V Tape & Reel 10k pcs/reel
AS1374-BWLT-1518
(1)
ASTK 6-bump WLCSP 1.5V 1.8V Tape & Reel 10k pcs/reel
AS1374-BWLT-1530
(1)
ASTX 6-bump WLCSP 1.5V 3.0V Tape & Reel 10k pcs/reel
AS1374-BWLT-2525
(1)
ASV7 6-bump WLCSP 2.5V 2.5V Tape & Reel 10k pcs/reel
AS1374-BWLT-1825
(1)
ASV8 6-bump WLCSP 1.8V 2.5V Tape & Reel 10k pcs/reel
AS1374-BWLT
(2)
____ 6-bump WLCSP tbd tbd Tape & Reel 10k pcs/reel
Ordering & Contact Information
Page 30 ams Datasheet
Document Feedback [v2-00] 2016-Jun-22
AS1374 − Ordering & Contact Information
Buy our products or get free samples online at:
www.ams.com/ICdirect
Technical Support is available at:
www.ams.com/Technical-Support
Provide feedback about this document at:
www.ams.com/Document-Feedback
For further information and requests, e-mail us at:
ams_sales@ams.com
For sales offices, distributors and representatives, please visit:
www.ams.com/contact
Headquarters
ams AG
Tobelbaderstrasse 30
8141 Premstaetten
Austria, Europe
Tel: +43 (0) 3136 500 0
Website: www.ams.com
ams Datasheet Page 31
[v2-00] 2016-Jun-22 Document Feedback
AS1374 − RoHS Compliant & ams Green Statement
RoHS: The term RoHS compliant means that ams AG products
fully comply with current RoHS directives. Our semiconductor
products do not contain any chemicals for all 6 substance
categories, including the requirement that lead not exceed
0.1% by weight in homogeneous materials. Where designed to
be soldered at high temperatures, RoHS compliant products are
suitable for use in specified lead-free processes.
ams Green (RoHS compliant and no Sb/Br): ams Green
defines that in addition to RoHS compliance, our products are
free of Bromine (Br) and Antimony (Sb) based flame retardants
(Br or Sb do not exceed 0.1% by weight in homogeneous
material).
Important Information: The information provided in this
statement represents ams AG knowledge and belief as of the
date that it is provided. ams AG bases its knowledge and belief
on information provided by third parties, and makes no
representation or warranty as to the accuracy of such
information. Efforts are underway to better integrate
information from third parties. ams AG has taken and continues
to take reasonable steps to provide representative and accurate
information but may not have conducted destructive testing or
chemical analysis on incoming materials and chemicals. ams AG
and ams AG suppliers consider certain information to be
proprietary, and thus CAS numbers and other limited
information may not be available for release.
RoHS Compliant & ams Green
Statement
Page 32 ams Datasheet
Document Feedback [v2-00] 2016-Jun-22
AS1374 − Copyright s & Disclaimer
Copyright ams AG, Tobelbader Strasse 30, 8141 Premstaetten,
Austria-Europe. Trademarks Registered. All rights reserved. The
material herein may not be reproduced, adapted, merged,
translated, stored, or used without the prior written consent of
the copyright owner.
Devices sold by ams AG are covered by the warranty and patent
indemnification provisions appearing in its General Terms of
Trade. ams AG makes no warranty, express, statutory, implied,
or by description regarding the information set forth herein.
ams AG reserves the right to change specifications and prices
at any time and without notice. Therefore, prior to designing
this product into a system, it is necessary to check with ams AG
for current information. This product is intended for use in
commercial applications. Applications requiring extended
temperature range, unusual environmental requirements, or
high reliability applications, such as military, medical
life-support or life-sustaining equipment are specifically not
recommended without additional processing by ams AG for
each application. This product is provided by ams AG “AS IS”
and any express or implied warranties, including, but not
limited to the implied warranties of merchantability and fitness
for a particular purpose are disclaimed.
ams AG shall not be liable to recipient or any third party for any
damages, including but not limited to personal injury, property
damage, loss of profits, loss of use, interruption of business or
indirect, special, incidental or consequential damages, of any
kind, in connection with or arising out of the furnishing,
performance or use of the technical data herein. No obligation
or liability to recipient or any third party shall arise or flow out
of ams AG rendering of technical or other services.
Copyrights & Disclaimer
ams Datasheet Page 33
[v2-00] 2016-Jun-22 Document Feedback
AS1374 − Document Status
Document Status Product Status Definition
Product Preview Pre-Development
Information in this datasheet is based on product ideas in
the planning phase of development. All specifications are
design goals without any warranty and are subject to
change without notice
Preliminary Datasheet Pre-Production
Information in this datasheet is based on products in the
design, validation or qualification phase of development.
The performance and parameters shown in this document
are preliminary without any warranty and are subject to
change without notice
Datasheet Production
Information in this datasheet is based on products in
ramp-up to full production or full production which
conform to specifications in accordance with the terms of
ams AG standard warranty as given in the General Terms of
Trade
Datasheet (discontinued) Discontinued
Information in this datasheet is based on products which
conform to specifications in accordance with the terms of
ams AG standard warranty as given in the General Terms of
Trade, but these products have been superseded and
should not be used for new designs
Document Status
Page 34 ams Datasheet
Document Feedback [v2-00] 2016-Jun-22
AS1374 − Revision Information
Note(s):
1. Page and figure numbers for the previous version may differ from page and figure numbers in the current revision.
2. Correction of typographical errors is not explicitly mentioned.
Changes from 1.8 (2011-Dec-12) to current revision 2-00 (2016-Jun-22) Page
Content of austriamicrosystems datasheet was converted to latest ams design
Added benefits to Key Features
Updated all drawings
Updated Figure 6 5
Updated Typical Operating Characteristics section 8
Updated Package Drawings & Markings section 27
Updated Figure 35 29
Revision Information
ams Datasheet Page 35
[v2-00] 2016-Jun-22 Document Feedback
AS1374 − Content Guide
1 General Description
1 Key Benefits & Features
2 Applications
3Block Diagram
4Pin Assignment
5Absolute Maximum Ratings
6 Electrical Characteristics
8 Typical Operating Characteristics
19 Detailed Description
19 Output Voltage
19 Enable
19 Current Limit
19 Thermal Protection
20 Application Information
20 Dropout Voltage
21 Efficiency
21 Power Dissipation
22 Junction Temperature
23 Explanation of Steady State Specifications
23 Line Regulation
23 Load Regulation
23 Setting Accuracy
24 Total Accuracy
24 Explanation of Dynamic Specifications
24 Power Supply Rejection Ratio (PSRR)
24 Output Capacitor ESR
25 Input Capacitor
25 Noise
25 Transient Response
26 Turn On Time
26 Thermal Protection
27 Package Drawings & Markings
29 Ordering & Contact Information
31 RoHS Compliant & ams Green Statement
32 Copyrights & Disclaimer
33 Document Status
34 Revision Information
Content Guide
