1A Positive Voltage
Regulators (Preliminary)
Description
The
CYT8117
series of high performance low dropout
voltage regulators are designed for applications that
require efficient conversion and fast transient
response.
CYT8117
Features
Low Dropout Performance.
Guaranteed 1A Output Current.
Wide Input Supply Voltage Range.
Over-temperature and Over-current
Protection.
Fixed or Adjustable Output Voltage.
Tab is Vout
Pin Configuration
Rugged 3KV ESD withstand capability.
Available in SOT-223 Packages.
1
2
3
Application
In
Adj/Gnd Out
Front View
Active SCSI Terminators.
High Efficiency Linear Regulators.
5V to 3.3V Linear Regulators
Motherboard Clock Supplies.
SOT-223
Ordering Information
Device
CYT8117TXX
CYT8117TA
CYT8117TXXLF
CYT8117TALF
SOT-223
(Lead-free)
Package
V
OUT
Volts
Fixed output voltages; XX denotes voltage options (1.5V, 1.8V, 2.5V,
SOT-223
3.0V, and 3.3V).
Adjustable output voltage.
Fixed output voltages; XX denotes voltage options (1.5V, 1.8V, 2.5V,
3.0V, and 3.3V).
Adjustable output voltage.
Absolute Maximum Rating
Symbol
V
IN
θ
JA
T
J
T
STG
T
LEAD
Parameter
Input Supply Voltage
Thermal Resistance Junction to Ambient
SOT-223
Operating Junction Temperature Range
Storage Temperature Range
Lead Temperature (Soldering 10 Sec)
Maximum
9
60
0 to 125
-40 to 150
260
Units
V
°C/W
°C
°C
°C
Preliminary and all contents are subject to change without prior notice.
1
1A Positive Voltage
Regulators (Preliminary)
CYT8117
Electrical Characteristic
V
IN,MAX
≤
8V, V
IN,MIN
– V
OUT
= 1.5V, I
OUT
= 10mA, C
IN
= 10µF, C
OUT
= 22µF, T
J
= 0 – 125°C, unless otherwise specified.
Symbol
Parameter
Test Condition
(V
IN
- V
OUT
) = 1.5V, I
OUT
= 10mA,
T
A
= 25°C,
CYT8117T15
Min
Typ
Max
Units
1.5
(-2%)
1.8
2.5
3.0
3.3
(-2%)
--
--
--
--
1.250 (+2%)
0.3
0.4
10
48
0.2
1.1
4
1.8
0.07
175
0.003
35
--
--
--
--
--
--
--
--
--
--
--
--
V
%
%
mA
µA
µA
V
mA
A
%/°C
°C
%V
O
dB
(+2%)
V
V
O
Output Voltage
(1)
CYT8117T18
CYT8117T25
CYT8117T30
CYT8117T33
V
REF
V
SR
V
LR
I
Q
I
ADJ
∆I
ADJ
V
D
I
O
I
CL
T
C
OTP
V
N
R
A
Notes:
1.
2.
Reference Voltage
(1)
(Adj. Voltage Version)
Line Regulation
(1)
Load Regulation
(1)
Quiescent Current
Adjust Pin Current
Adjust Pin Current
Change
Dropout Voltage
(2)
Minimum Load Current
Current Limit
Temperature Coefficient
Thermal Protection
RMS Output Noise
Ripple Rejection Ratio
(V
IN
- V
OUT
) = 1.5V
I
OUT
= 10mA
V
OUT
+ 1.5V < V
IN
< 8V
I
OUT
= 10mA
(V
IN
- V
OUT
) = 1.5V
10mA
≤
I
OUT
≤
1A
Fixed Output Version
V
OUT
+ 1.5V < V
IN
< 8V
10mA
≤
I
OUT
≤
1A
∆V
REF
= 1%, I
OUT
= 1A
--
--
--
--
--
--
T
A
= 25°C, 10Hz
≤
f
≤
10kHz
f = 120Hz,
C
OUT
= 22µF (Tantalum),
(V
IN
- V
OUT
) = 3V, I
OUT
= 1A
--
--
Low duty cycle pulse testing with which T
J
remains unchanged.
∆V
OUT
,
∆V
REF
= 1%.
Preliminary and all contents are subject to change without prior notice.
2
1A Positive Voltage
Regulators (Preliminary)
CYT8117
Typical Application
Adjustable Voltage Regulator
V
IN
>= 3.0V
3
CYT8117TA
2
V
OUT
= 1.5V
V
REF
C
IN
10uF
1
R1
124 Ohm
C
OUT
22uF
I
ADJ
R2
24.9 Ohm
Fixed Voltage Regulator
V
IN
>= 4.8V
3
CYT8117T33
2
V
OUT
= 3.3V
C
IN
10uF
1
I
Q
C
OUT
22uF
Preliminary and all contents are subject to change without prior notice.
3
1A Positive Voltage
Regulators (Preliminary)
Application Hints
Like any linear voltage regulator,
CYT8117
requires
external capacitors to ensure stability.
ensure performance.
The
external capacitors must be carefully selected to
CYT8117
Thermal Considerations
It is important that the thermal limit of the package
is not exceeded.
thermal protection.
The
CYT8117
has built-in
When the thermal limit is
exceeded, the IC will enter protection, and V
OUT
will be pulled to ground. The power dissipation
for a given application can be calculated as
following:
The power dissipation (P
D
) is
P
D
= I
OUT
* [V
IN
– V
OUT
]
It
The thermal limit of the package is then limited to
P
D(MAX)
= [T
J
– T
A
]/Θ
JA
where T
J
is the junction
temperature, TA is the ambient temperature, and
Θ
JA
is around 60°C/W for
CYT8117.CYT8117
is
designed to enter thermal protection at 175°C.
For example, if T
A
is 25°C then the maximum P
D
is limited to about 2.5W.
2.5V.
In other words, if
I
OUT(MAX)
= 1A, then [V
IN
– V
OUT
] cannot exceed
Input Capacitor
An input capacitor of at least 10µF is required.
Ceramic or Tantalum can be used.
can be increase without upper limit.
The value
Output Capacitor
An output capacitor is required for stability.
must be placed no more than 1 cm away from the
V
OUT
pin, and connected directly between V
OUT
and GND pins. The minimum value is 22µF but
may be increase without limit.
Preliminary and all contents are subject to change without prior notice.
4
1A Positive Voltage
Regulators (Preliminary)
CYT8117
Typical Performance Characteristics
Reference Voltage vs Junction Temperature
1250
Reference Voltage (mV)
1245
1240
1235
1230
1225
1220
-25
0
25
50
75
100
125
150
Junction Temperature (C)
Line Transients
V
IN
= 4.5V – 5.5 V
C
IN
= 0.1µF, C
OUT
= 1µF
Output Voltage vs Junction Temperature
3.70
3.65
3.60
Output Voltage
3.55
3.50
3.45
3.40
3.35
3.30
3.25
3.20
-25
0
25
50
75
100
125
150
Junction Temperature (C)
Load Transients
I
LOAD
= 10mA – 1A
C
OUT
= 22µF, C
IN
= 10µF
Dropout Voltage vs Output Current
1.14
1.12
Dropout Voltage (V)
1.1
1.08
1.06
1.04
1.02
1
0
200
400
600
800
1000
Output Current (mA)
Preliminary and all contents are subject to change without prior notice.
5