800mA LOW DROPOUT POSITIVE REGULATORS
ADJUSTABLE AND FIXED 2.85V, 3.30V, 5.00V
PRELIMINARY INFORMATION
TCL1117
TCL1117
TCL1117-2.85
TCL1117-2.85
TCL1117-3.30
TCL1117-3.30
TCL1117-5.00
TCL1117-5.00
800mA LOW DROPOUT POSITIVE REGULATORS
ADJUSTABLE AND FIXED 2.85V, 3.30V, 5.00V
FEATURES
s
s
s
s
s
s
s
s
Space-saving SOT-223 Package
Pin Compatible with Older Adjustable 3 Terminal
Regulators
Adjustable or Fixed Voltages of 2.85V, 3.30V or 5.00V
High Output Current ..................................... 800mA
Low Dropout Voltage ............ 1.2V at I
OUT
= 800mA
Guaranteed Dropout Voltage at Multiple Current
Levels
Line Regulation (Max) ...................................... 0.2%
Load Regulation (Max) ..................................... 0.4%
GENERAL DESCRIPTION
The TCL1117 is a low-dropout positive voltage regula-
tor (LDO) with 800mA output current capability. It is available
in fixed and adjustable output voltage versions, 2.85V (ac-
tive SCSI terminators), 3.30V and 5.00V. Output/reference
voltage accuracy is guaranteed to
±1.0%.
Over-current
protection is integrated onto the chip. Dropout is specified
at 1.2V maximum at full rated output current and less than
1.0V at low loads (<100mA). The SOT-223 package makes
the TCL1117 especially attractive for tight physical layouts.
For stability, a 10µF output capacitor is required. The
TCL1117 is an NPN-based design which has significantly
lower unused quiescent current than similar PNP-based
regulators.
PIN CONFIGURATIONS
SOT-223
3-Lead Package
FRONT VIEW
APPLICATIONS
s
s
s
s
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Active SCSI Terminators
High Efficiency Linear Regulators
Post Regulators for Switching Supplies
Battery Chargers
5V - 3.3V Linear Regulators
DDPAK-3
FRONT VIEW
ORDERING INFORMATION
Part Number*
TCL1117-ADJCDB
TCL1117-2.85CDB
TCL1117-3.30CDB
TCL1117-5.00CDB
TCL1117-ADJCEB
TCL1117-2.85CEB
TCL1117-3.30CEB
TCL1117-5.00CEB
Package
SOT-223-3
SOT-223-3
SOT-223-3
SOT-223-3
DDPAK-3
DDPAK-3
DDPAK-3
DDPAK-3
Part Marking
1117
11172
11173
11175
IN
TAB IS V
OUT
3
2
OUT
1
2
3
1
ADJ/GND
ADJ/GND
OUT
*Ambient temperature range is determined by maximum operating
power dissipation and a maximum die temperature of 125°C (see Power
Dissipation and Thermal Design Section).
TYPICAL APPLICATION
110Ω
IN
TCL1117-5.00
OUT
GND
110Ω
110Ω
18 to 27
LINES
4.75V to 5.25V
10µF
22µF
Active Terminator for SCSI-2 Bus
TCL1117-05 6/5/97
1
TelCom Semiconductor reserves the right to make changes in the circuitry and specifications of its devices.
IN
PRELIMINARY INFORMATION
TCL1117
TCL1117-2.85
TCL1117-3.30
TCL1117-5.00
ABSOLUTE MAXIMUM RATINGS*
800mA LOW DROPOUT POSITIVE REGULATORS
ADJUSTABLE AND FIXED 2.85V, 3.30V, 5.00V
Input Voltage
Operating Voltage:
TCL1117, TCL1117-3.30, TCL1117-5.00 ...... 15V
TCL1117-2.85 ................................................10V
Surge Voltage:
TCL1117, TCL1117-3.30, TCL1117-5.00 ...... 20V
Operating Junction Temperature ............... 0°C to +125°C
Storage Temperature ............................ – 65°C to +150°C
Lead Temperature (Soldering 10 sec) .................... 300°C
*Stresses beyond those listed under "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 the operational sections of the specifications is not
implied. Exposure to absolute maximum rating conditions for extended
periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
Symbol
Parameter
Reference
Voltage
Output Voltage
TCL1117
TCL1117-2.85
Test Conditions
I
OUT
= 10mA, (V
IN
– V
OUT
) = 2V, T
J
= 25°C
10
≤
I
OUT
≤
800mA, 1.4V
≤
(V
IN
– V
OUT
)
≤
10V (Note 1)
I
OUT
= 10mA, V
IN
= 4.85V, T
J
= 25°C
0
≤
I
OUT
≤
800mA, 4.25V
≤
V
IN
≤
10V (Note 1)
0
≤
I
OUT
≤
500mA, V
IN
= 3.95V (Note 1)
I
OUT
= 10mA, V
IN
= 5.3V, T
J
= 25°C
0
≤
I
OUT
≤
800mA, 4.75V
≤
V
IN
≤
10V (Note 1)
I
OUT
= 10mA, V
IN
= 7V, T
J
= 25°C
0
≤
I
OUT
≤
800mA, 6.50V
≤
V
IN
≤
12V (Note 1)
I
OUT
= 10mA, 1.5V
≤
V
IN
– V
OUT
≤
15V (Notes 1 & 2)
I
OUT
= 0mA, 4.25V
≤
V
IN
≤
10V (Notes 1 & 2)
I
OUT
= 0mA, 4.75V
≤
V
IN
≤
15V (Notes 1 & 2)
I
OUT
= 0mA, 6.5V
≤
V
IN
≤
15V (Notes 1 & 2)
(V
IN –
V
OUT
) = 3V, 10mA,
≤
I
OUT
≤
800mA (Notes 1 & 2)
V
IN
= 4.25V, 0
≤
I
OUT
≤
800mA (Notes 1 & 2)
V
IN
= 4.75V, 0
≤
I
OUT
≤
800mA (Notes 1 & 2)
V
IN
= 6.5V, 0
≤
I
OUT
≤
800mA (Notes 1 & 2)
I
OUT
= 100mA, (Note 1 & 3)
I
OUT
= 500mA, (Note 1 & 3)
I
OUT
= 800mA, (Note 1 & 3)
(V
IN –
V
OUT
) = 5V, T
J
= 25°C
(V
IN –
V
OUT
) = 15V (Note 1 & 4)
V
IN
≤
10V (Note 1)
V
IN
≤
15V (Note 1)
V
IN
≤
15V (Note 1)
T
A
= 25°C, 30msec Pulse
f
RIPPLE
= 120Hz (V
IN
– V
OUT
) = 3V, V
RIPPLE
= 1Vp-p ( Note 1)
(Note 1)
10mA
≤
I
OUT
≤
800mA, 1.4V
≤
(V
IN
– V
OUT
)
≤
10V (Note 1)
T
A
= 125°C, 1000 Hrs.
(% of V
OUT
)
,
10Hz
≤
f
≤
10kHz
(Junction to Case, at Tab)
Min
1.238
1.225
2.820
2.790
2.790
3.265
3.230
4.950
4.900
—
—
—
—
—
—
—
—
—
—
—
800
—
—
—
—
—
60
—
—
—
—
—
—
Typ
1.250
1.250
2.850
2.850
2.850
3.300
3.300
5.000
5.000
0.035
1
1
1
0.1
1
1
1
1.00
1.05
1.10
950
1.7
5
5
5
0.01
75
55
0.2
0.5
0.3
0.003
15
Max
1.262
1.270
2.880
2.910
2.910
3.335
3.370
5.050
5.100
0.2
6
7
10
0.4
10
12
15
1.10
1.15
1.20
1200
5
10
10
10
0.1
—
120
5
—
—
—
—
Unit
V
V
TCL1117-3.30
TCL1117-5.00
Line Regulation
TCL1117
TCL1117-2.85
TCL1117-3.30
TCL1117-5.00
TCL1117
TCL1117-2.85
TCL1117-3.30
TCL1117-5.00
V
V
%
mV
Load Regulation
%
mV
Dropout Voltage
V
Current Limit
Minimum Load
Current
Quiescent
Current
TCL1117
mA
mA
mA
TCL1117-2.85
TCL1117-3.30
TCL1117-5.00
Thermal Regulation
Ripple Rejection
Adjust Pin Current
Adjust Pin Current Change
Temperature Stability
Long Term Stability
RMS Output Noise
Thermal Resistance
%W
dB
µA
µA
%
%
%
°C/W
NOTES:
1. Specifications apply over the full operating temperature range.
2. See thermal regulation specification for changes in output voltage due to heating effects. Load regulation and line regulation are
measured at a constant junction temperature by low duty cycle pulse testing.
3. Dropout voltage is specified over the full output current range of the device. Dropout voltage is defined as the minimum input/output
differential measured at the specified output current. Test points and limits are also shown on the Dropout Voltage curve.
4. Minimum load current is defined as the minimum output current required to maintain regulation.
TCL1117-05 6/5/97
2
800mA LOW DROPOUT POSITIVE REGULATORS
ADJUSTABLE AND FIXED 2.85V, 3.30V, 5.00V
PRELIMINARY INFORMATION
TCL1117
TCL1117-2.85
TCL1117-3.30
TCL1117-5.00
APPLICATIONS
Overload Protection
The TCL1117 is protected against current (short-circuit)
and thermal overload conditions. Thermal protection is
triggered by a chip temperature exceeding 165°C. Current
overload is triggered at approximately 950mA.
currents can be high enough to damage the chip. In this
case, a high-current, fast-response diode is recommended.
(See Figure 1).
Output Voltage Adjust
Like most LDOs, the TCL1117 regulates the output by
comparing the output voltage, or a multiple thereof, to an
internally generated reference voltage. On the adjustable
version, the V
REF
is available externally as 1.25V (±1%)
between V
OUT
and ADJ (See Figure 2). The voltage divider
formed by R1 and R2 should be set to conduct 10mA
(minimum output load). The output voltage is given by the
following equation:
V
OUT
= V
REF
R2
(
1+ R1
)
+ I
ADJ
Stability and Load Regulation
The TCL1117 requires a capacitor from V
OUT
to GND to
provide compensation feedback to the internal gain stage.
This is to ensure stability at the output terminal. Typically, a
10µF tantalum or 50µF aluminum electrolytic is sufficient.
NOTE: It is important that the ESR for this capacitor does not
exceed 0.5Ω.
The output capacitor does not have a theoretical upper
limit and increasing its value will increase stability.
C
OUT
= 100µF or more is typical for high current regulator
designs. NOTE: See Protection Diodes for limitations. An-
other benefit of larger output capacitance is improved tran-
sient load response (large di/dt in the load).
R2
On fixed voltage versions of the TCL1117, the voltage
divider is provided internally.
Load Regulation
The TCL1117 load regulation is limited by the resistance
of the wire connecting it to the load (R
p
, Figure 3). For the
adjustable version, the best load regulation is accomplished
when the top of the resistor divider (R1) is connected directly
to the output pin of the TCL1117, NOT to the high side of the
load (Figure 3). When so connected, R
p
is not multiplied by
the divider ratio. For the fixed output versions, the top of R1
is internally connected to the output and the ground pin can
be connected to the low side of the load as a negative side
sense if, so desired.
Protection Diodes
Typically no protection diodes are necessary for the
TCL1117. Unlike older regulators, the ADJ pin is protected
internally from excessive currents. The ADJ pin can be
driven with voltage transients as high as
±25V
with respect
to the output without damage to the device.
Likewise, a diode between the input and output is not
typically required. If the input voltage collapses the internal
circuitry can absorb ~20A transient currents (<10µsec)
without damage. This reverse current is much larger than
most power supply designs can generate. However, if the
output capacitor is VERY large (>1000µF), instantaneous
D1
1N4002
(OPTIONAL)
VIN
VIN
IN
TCL1117
ADJ
OUT
VOUT
IN
TCL1117
ADJ
IADJ
50µA
OUT
VREF
R1
VOUT
+
R1
COUT
150µF
+
VOUT = VREF 1+ R2
R1
CADJ
10µF
R2
(
)
+ IADJ R2
R2
Figure 1.
TCL1117-05 6/5/97
Figure 2. Basic Adjustable Regulator
3
PRELIMINARY INFORMATION
TCL1117
TCL1117-2.85
TCL1117-3.30
TCL1117-5.00
800mA LOW DROPOUT POSITIVE REGULATORS
ADJUSTABLE AND FIXED 2.85V, 3.30V, 5.00V
Table 1.
Rp
PARASITIC
LINE RESISTANCE
VIN
IN
TCL1117
ADJ
OUT
Copper Area
Topside*
2500 Sq. mm
1000 Sq. mm
Thermal
Resistance
45
°
C/W
45
°
C/W
53
°
C/W
59
°
C/W
52
°
C/W
55
°
C/W
Backside Board Area
(Junction-to-Ambient)
2500 Sq. mm
2500 Sq. mm
2500 Sq. mm
2500 Sq. mm
1000 Sq. mm
0
2500 Sq. mm
2500 Sq. mm
2500 Sq. mm
2500 Sq. mm
1000 Sq. mm
1000 Sq. mm
R1
CONNECT
R1 TO CASE
R2
RL
225 Sq. mm
100 Sq. mm
1000 Sq. mm
1000 Sq. mm
*Tab of device attached to topside copper
CONNECT
R2 TO LOAD
Soldering Methods
The recommended methods of soldering the SOT-223
package are: vapor phase re-flow and infrared re-flow with
component preheat within 65°C of the solder temperature.
Hand soldering and wave soldering methods are not recom-
mended since they can damage the part with excessive
thermal gradients across the surface area of the package.
Thermal shock to the package (>30°C per second) must be
minimized.
Figure 3. Connections for Best Load Regulation
Power Dissipation and Thermal Design
As mentioned earlier, the TCL1117 has thermal over-
load protection which limits internal temperature to +165°C.
However, device functionality is only guaranteed to a maxi-
mum junction temperature of +125°C. Since internal power
dissipation can be >1 watt, careful thermal design is essen-
tial. The TCL1117 is supplied in a SOT-223 package which
is intended to be directly surface-mounted to the PC-board.
Because there is no dedicated heat sink, power dissipation
to ambient is performed largely by the PC board and its
copper material.
The power dissipation and junction temperature for the
TCL1117 in a SOT-223 are given by the following equations:
P
D
= (V
IN
– V
OUT
) x (I
OUT
)
T
JUNCTION
= T
AMBIENT
+ (P
D
x
Θ
JA
)
NOTE: T
JUNCTION
must not exceed 125°C
The
Θ
JC
(junction to external tab) for the SOT-223 is
15°C/W. Depending upon heatsink parameters, the
Θ
CA
can
be as low as 30°C/W. Therefore, the total thermal resistance
(Θ
JA
) is at least 45°C/W. Table 1 shows thermal resistance
measurements taken with the TCL1117 mounted on 1/16
inch 2-layer PCB with 1oz. copper foil. NOTE: The TAB pin
does not have to be soldered to all copper layers for effective
heat transfer. Use Table 1 only as a rough guide since
thermal interactions with adjacent components cannot be
predicted.
TCL1117-05 6/5/97
Ripple Rejection
Ripple Rejection curves were generated using an ad-
justable output TCL1117 with a bypass capacitor from ADJ
to ground. To obtain the performance shown in the curves,
the impedance of the bypass capacitor (at the ripple fre-
quency) should be less than R1. R1 is typically 100Ω to
200Ω. For example at 120Hz, with R1 = 100Ω, the adjust
capacitor should be at least 13µF. Only 0.16µF would be
required at 10kHz.
The output ripple increases as the ratio of the output
voltage to the reference voltage (V
OUT
/V
REF
) in fixed voltage
devices, and adjustable devices without an adjust pin ca-
pacitor. For example, at 5V, output ripple will increase by a
factor of 4 (5/1.25V). Ripple rejection will be reduced by 12db
from the value shown on the curve.
4
800mA LOW DROPOUT POSITIVE REGULATORS
ADJUSTABLE AND FIXED 2.85V, 3.30V, 5.00V
PRELIMINARY INFORMATION
TCL1117
TCL1117-2.85
TCL1117-3.30
TCL1117-5.00
TYPICAL APPLICATIONS
1.2V-10V Adjustable Regulator
5V Regulator with Shutdown
VIN
IN
TCL1117
ADJ
OUT
R1
121Ω
+
VOUT**
VIN
+
10µF
IN
TCL1117
ADJ
OUT
121Ω
1%
+
365Ω
1%
5V
+
C1*
10µF
R2
1k
C2
100µF
1k
SHDN
1k
2N3904
100µF
* NEEDED IF DEVICE IS FAR FROM FILTER CAPACITORS
** VOUT = 1.25V 1+ R2
R1
(
)
Remote Sensing
Rp
(MAX DROP 300mV)
VIN
IN
TCL1117
ADJ
OUT
100µF
25Ω
+
+
6
1
10µF
121Ω
8
VIN
7
OUTPUT
5V
2
3
1kΩ
RL
–
+
4
LM301A
5µF
365Ω
100pF
+
RETURN
25Ω
RETURN
Adjusting Output Voltage of Fixed Regulators
Battery Charger
IF
VIN > 12V
10µF
+
IN TCL1117-5.00 OUT
GND
+
5V TO 10V
100µF
VIN
IN
TCL1117
OUT
RS
R1
VOUT
1.25V
ADJ
10µF*
+
1k
R2
VOUT – 1.25V
IF =
(
1+ R2
)
R1
– RS
(
1+ R2
)
R1
1
– RS
*OPTIONAL IMPROVES RIPPLE REJECTION
IF
=
VOUT
(
1+ R2
)
R1
TCL1117-05 6/5/97
5