IXD1233
High Speed LDO Regulator with Inrush Current Prevention
FEATURES
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Operating Voltage Range 1.7 V – 5.5 V
Output Voltage Range from 1.2 V to 3.6 V with
0.05 V increments
Output Voltage Accuracy ±1%
Output Current up to 200 mA
Dropout Voltage 240 mV @ 200 mA
Low Power Consumption at 45
µA
typical
Standby Current less than 0.1 µA typical
Ripple Rejection 75 dB at 1 kHz
Load Capacitor Auto Discharge
Current Limit and Short Circuit Protection
Low ESR Ceramic Capacitor compatible
0
Operating Ambient Temperature - 40 + 85 C
Packages : SOT-25, SSOT-24, and USP-4
EU RoHS Compliant, Pb Free
DESCRIPTION
The IXD1233 are a 200 mA highly precise, high
speed, low dropout voltage regulators with 75 dB @
1 kHz ripple rejection. They consist of a voltage
reference, an error amplifier, a current limiter with
inrush current prevention, a phase compensation
circuit, and a driver transistor.
Output voltage is selectable in 0.05V increments
within a range of 1.2 V ~ 3.6 V with ± 1% accuracy.
The IXD1233 are compatible with low ESR ceramic
capacitors, and due excellent transient response,
they maintain stability even during significant load
fluctuations. The current limiter's foldback circuit
operates also as a short circuit protection.
The chip enable (CE) function allows disable IC,
greatly
reducing
power
consumption
and
simultaneously discharge load capacitor to prevent
load malfunction.
Regulator is available in SOT-25, SSOT-24, and
USP-4 packages.
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APPLICATIONS
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Mobile phones
Cameras, VCRs
Various portable equipment
Reference voltage source
TYPICAL APPLICATION CIRCUIT
TYPICAL PERFORMANCE CHARACTERISTIC
Inrush Current Limit
C
IN
= C
L
= 1.0
µF
(ceramic), V
IN
= 2.8 V, V
OUT
= 1.8 V, V
CE
= 0 V
→
2.8 V, tr = 5
µs,
Ta = 25
0
C
© 2014 IXYS Corp.
Characteristics subject to change without notice
1
Doc. No. IXD1233_DS, Rev. N0
IXD1233
ABSOLUTE MAXIMUM RATINGS
PARAMETER
Input Voltage
Output Current
Output Voltage
CE Input Voltage
SOT-25
Power Dissipation
2)
SYMBOL
V
IN
I
OUT
V
OUT
V
CE
SSOT-24
USP-4
P
D
T
OPR
T
STG
RATINGS
– 0.3 ~ +6.0
275
1)
UNITS
V
mA
V
V
mW
0
0
– 0.3 ~ V
IN
+ 0.3 or +6.0 V
2)
– 0.3 ~ +6.0
600 (PCB mounted)
500 (PCB mounted)
1000 (PCB mounted)
– 40 ~ + 85
– 55 ~ +125
Operating Temperature Range
Storage Temperature Range
C
C
All voltages are in respect to V
SS
1) I
OUT
≤
Pd/ (V
IN
-V
OUT
)
2) The lowest value between V
IN
+ 0.3 and 6.0 V
3) This is a reference data taken by using the test board. Please refer to page 18 to 20 for details
ELECTRICAL OPERATING CHARACTERISTICS
Ta = 25
0
C
PARAMETER
Output Voltage
1)
Maximum Output Current
Load Regulation
Dropout Voltage
2)
Supply Current
Standby Current
Line Regulation
Input Voltage
Output Voltage Temperature
Characteristics
Power Supply Rejection Ratio
Current Limit
Short Current
CE “H” Level Voltage
CE “L” Level Voltage
CE “H” Level Current
CE “L” Level Current
C
L
Discharge Resistance
Inrush Current
NOTE:
Unless otherwise stated, V
IN
= V
CE
= V
OUT (T)
+1.0 V. I
OUT
= 1 mA
1) V
OUT (T)
is Nominal output voltage and V
OUT (E)
is Effective output voltage, (I.e. the output voltage when "V
OUT (T)
+1.0V" is provided at the
V
IN
pin, while maintaining a certain I
OUT
value).
2) V
DIF
= {V
IN
-V
OUT
}, where V
IN1
is the input voltage when V
OUT
= 0.98 V
OUT(T)
appears, while input voltage gradually decreases
3) Refer to the Table “Voltage Chart. Output Voltage”
4) Refer to the Table “Voltage Chart, Dropout Voltage”
SYMBOL
V
OUT(E)
I
OUT_MAX
∆V
OUT
V
DIF1
I
SS
I
STB
∆
∆
V
IN
∆
∆
PSRR
I
LIM
I
SHORT
V
CEH
V
CEL
I
CEH
I
CEL
R
DCH
I
R
V
OUT
= V
SS
0.9
V
CE
= V
IN
= 5.5 V
V
CE
= V
SS
V
IN
= 5.5 V, V
CE
= 0 V, V
OUT
= 2 V
V
IN
= 5.5 V, V
CE
= 0 V
→
5.5 V
2.5
-0.1
6.0
270
95
CONDITIONS
V
OUT(T)
≥
2 V
3)
V
OUT(T)
< 2 V
3)
0.1 mA
≤
I
OUT
≤
200 mA
I
OUT
= 200 mA
I
OUT
= 0 mA
V
CE
= 0 V
I
OUT
= 30 mA, V
OUT(T)
+ 0.5 V
≤
V
IN
≤
5.5 V,
if V
OUT(T)
≥
2 V, or 2.5 V
≤
V
IN
≤
5.5 V
1.7
I
OUT
= 30 mA
- 40
0
C
≤
T
OPR
≤
85
0
C
V
IN
= (V
OUT(T)
+ 1.0 V) + 1 Vp-p
AC
;
,
when
V
OUT(T)
< 2.5 V, V
IN
= 3.0 V + 0.5 Vp-p
AC
,
V
CE
= V
OUT(T)
+ 1.0 V, I
OUT
= 30 mA,
f = 1 kHz
± 80
MIN.
V
OUT(T)
x
0.99
V
OUT(T)
-
0.02
200
TYP.
V
OUT(T)*
V
OUT(T)*
25
E-1
4)
45
0.01
0.02
MAX.
V
OUT(T)
x
1.01
V
OUT(T)
+
0.02
45
87
0.10
0.10
5.5
UNIT
V
mA
mV
mV
µA
µA
%/V
V
ppm/
0
C
CIRCUIT
75
200
60
255
V
IN
0.3
9.5
0.1
dB
mA
mA
V
V
µA
µA
Ω
mA
© 2014 IXYS Corp.
Characteristics subject to change without notice
2
Doc. No. IXD1233_DS, Rev. N0
IXD1233
ELECTRICAL OPERATING CHARACTERISTICS (CONTINUED)
Voltage Chart
NOMINAL
OUTPUT
VOLTAGE
V
OUT(T)
, V
1.20
1.25
1.30
1.35
1.40
1.45
1.50
1.55
1.60
1.65
1.70
1.75
1.80
1.85
1.90
1.95
2.00
2.05
2.10
2.15
2.20
2.25
2.30
2.35
2.40
2.45
E-0
Output Voltage
V
OUT(E)
, V
MIN
MAX
1.1800
1.2200
1.2300
1.2700
1.2800
1.3200
1.3300
1.3700
1.3800
1.4200
1.4300
1.4700
1.4800
1.5200
1.5300
1.5700
1.5800
1.6200
1.6300
1.6700
1.6800
1.7200
1.7300
1.7700
1.7800
1.8200
1.8300
1.8700
1.8800
1.9200
1.9300
1.9700
1.9800
2.0200
2.0295
2.0705
2.0790
2.1210
2.1285
2.1715
2.1780
2.2220
2.2275
2.2725
2.2770
2.3230
2.3265
2.3735
2.3760
2.4240
2.4255
2.4745
E-1
Dropout Voltage
V
DIF
, V
MIN
MAX
680
640
950
800
NOMINAL
OUTPUT
VOLTAGE
V
OUT(T)
, V
2.50
2.55
2.60
2.65
2.70
2.75
2.80
2.85
2.90
2.95
3.00
3.05
3.10
3.15
3.20
3.25
3.30
3.35
3.40
3.45
3.50
3.55
3.60
E-0
Output Voltage
V
OUT(E)
, V
MIN
MAX
2.4750
2.5250
2.5245
2.5755
2.5740
2.6260
2.6235
2.6765
2.6730
2.7270
2.7225
2.7775
2.7720
2.8280
2.8215
2.8785
2.8710
2.9290
2.9205
2.9795
2.9700
3.0300
3.0195
3.0805
3.0690
3.1310
3.1185
3.1815
3.1680
3.2320
3.2175
3.2825
3.2670
3.3330
3.3165
3.3835
3.3660
3.4340
3.4155
3.4845
3.4650
3.5350
3.5145
3.5855
3.5640
3.6360
E-1
Dropout Voltage
V
DIF
, V
MIN
MAX
310
420
600
695
510
630
400
600
240
380
375
520
© 2014 IXYS Corp.
Characteristics subject to change without notice
3
Doc. No. IXD1233_DS, Rev. N0
IXD1233
PIN CONFIGURATION
*The dissipation pad for the USP-3
package should be solder-plated in
recommended mounting pattern and
metal masking to enhance mounting
strength and heat release.
If the pad needs to be connected to
other pins, it should be connected to the
V
SS
(No.2) pin.
SOT-25 (TOP VIEW)
SSOT-24 (TOP VIEW)
USP-4 (BOTTOM VIEW)
PIN ASSIGNMENT
SOT-25
1
2
3
4
5
PIN NUMBER
SSOT-24
4
2
1
-
3
USP-4
4
2
3
-
1
PIN NAME
V
IN
V
SS
CE
NC
V
OUT
FUNCTIONS
Power Input
Ground
ON/OFF Control LOW or OPEN – Standby mode, HIGH - Active
No Connection
Output Voltage
BLOCK DIAGRAM
IXD1233H
Diodes inside the circuits are ESD protection diodes and parasitic diodes.
BASIC OPERATION
The Error Amplifier of the IXD1233 series monitors output voltage divided by internal resistors R1 & R2 and
compares it with the internal Reference Voltage (see Block Diagram above). The output signal from error amplifier
drives gate of the P-channel MOSFET, which is connected to the V
OUT
pin and operates as a series voltage
regulator.
The Current Limit and Short Protection circuits monitor level of the output current. The CE pin allows shutdown
internal circuitry to minimize power consumption.
Low ESR Capacitors
An internal phase compensation circuit guarantees stable IXD1233 operation even if output capacitors with low
ESR are used. However, connect the output capacitor C
L
as close to the V
OUT
and the V
SS
pins as possible to
prevent effectiveness of the phase compensation from degrade. The C
L
capacitance value should be at least 1µF.
In case the capacitor depends on the bias and temperature, make sure that actual capacitance is maintained at
operating voltage and temperature range. In addition, an input capacitor C
IN
≥
0.1µF between the V
IN
and V
SS
pins
should be used to ensure a stable input power.
© 2014 IXYS Corp.
Characteristics subject to change without notice
4
Doc. No. IXD1233_DS, Rev. N0
IXD1233
Current Limiter, Short-Circuit Protection
The IXD1233 series include a combination of a fixed current limiter circuit & a foldback circuit, which aid the
operations of the current limiter and circuit protection. When the load current reaches the current limit level, the
fixed current limiter circuit activates and output voltage drops. Because of this drop, the foldback circuit activates
too, and output voltage drops further decreasing output current. When the output pin is shorted, a current of about
60 mA flows.
CE Pin
The CE pin allows shutdown internal circuitry to minimize power consumption. In shutdown mode, output at the
V
OUT
pin is pulled down to the V
SS
level via R
DCH
resistor and N-channel switch.
Note that the IXD1233 CE input is active HIGH with pull down resistor. IC will be in shutdown mode, if CE pin is
open.
C
L
High-speed Discharge Function
The N-channel transistor located between V
OUT
and V
SS
pins quickly discharge the output capacitor (C
L
), when the
CE pin does low. The discharge time of the output capacitor (C
L
) is set by the C
L
auto-discharge resistance R
DCH
=
270
Ω
(TYP.) and the output capacitance (C
L
).
Time constant
τ
= C
L
x R
DCH
determines the output voltage after discharge as
V = V
OUT (E)
× e-t/τ
where: V
OUT (E)
- Output voltage, and t - Discharge time
Discharge time can be calculated also by the next formula:
t =τ x ln (V
OUT (E)
/V)
Inrush Current Prevention
The IXD1233 has a build-in inrush current prevention circuit. When the IC starts to operate, the circuit limits inrush
current at 95 mA (TYP.) to charge C
L
capacitor. However, the device cannot provide output current above this value
for approximately 100
µs
because of function of this limiter.
TYPICAL APPLICATION CIRCUIT
The output capacitor C
L
≥
1
µF
should be connected between the output pin (V
OUT
) and the V
SS
pin for stable regulator’s operation.
Ceramic capacitors with low ESR are recommended.
LAYOUT AND USE CONSIDERATIONS
1. Mount external component as close to the IC as possible and use thick, short connecting traces to
reduce the circuit impedance.
2. The IC may malfunction if absolute maximum ratings are exceeded.
3. If power source of this regulator is a high impedance device with impedance of 10
Ω
or more, an input
capacitor C
IN
≥
1µF should be used to prevent oscillations.
4. In case of high output current, increasing the input capacitor value can stabilize operations.
5. Oscillations may occur also, if the input capacitor value is not enough to reduce the input impedance
and the output capacitor C
L
is large. In such case, operations can be stabilized by either increasing the
input capacitor or reducing the output capacitor.
6. During start-up, IC provides constant current until V
OUT
= V
OUT (T)
.
7. Please ensure that output current I
OUT
is less than
P
D
/ (V
IN
- V
OUT
),
where P
D
is a rated power
dissipation value of the package shown at ABSOLUTE MAXIMUM RATING table to not exceed it.
© 2014 IXYS Corp.
Characteristics subject to change without notice
5
Doc. No. IXD1233_DS, Rev. N0
Test/Measurement
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