LT1763CS8#TRPBF Linear Technology, LT1763CS8#TRPBF Datasheet - Page 16

• Manufacturer Part Number: LT1763CS8#TRPBF
• Description: IC LDO REG LOW NOISE ADJ 8-SOIC
• Manufacturer: Linear Technology

Specifications of LT1763CS8#TRPBF

• Regulator Topology: Positive Adjustable
• Voltage - Output: 1.22 ~ 20 V
• Voltage - Input: 1.8 ~ 20 V
• Voltage - Dropout (typical): 0.3V @ 500mA
• Number Of Regulators: 1
• Current - Output: 500mA
• Current - Limit (min): 520mA
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (3.9mm Width)
• Voltage Regulator Type: Linear
• Topology: LDO
• Regulator Output Type: Adjustable
• Polarity Type: Positive
• Number Of Outputs: Single
• Input Voltage (min): 1.8V
• Input Voltage (max): 20V
• Output Voltage: 1.22 to 20V
• Package Type: SOIC N
• Output Current: 500mA
• Load Regulation: 6mV
• Line Regulation: 5mV
• Operating Temp Range: -40C to 125C
• Operating Temperature Classification: Automotive
• Dropout Voltage@current (max): 0.19@10mA/0.22@50mA
• Dropout Voltage@current (typ): 0.13@10mA/0.17@50mA
• Pin Count: 8
• Mounting: Surface Mount
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

LT1763 Series
APPLICATIONS INFORMATION
Output Capacitance and Transient Response
The LT1763 regulators are designed to be stable with a
wide range of output capacitors. The ESR of the output
capacitor affects stability, most notably with small capaci-
tors. A minimum output capacitor of 3.3μF with an ESR
of 3Ω, or less, is recommended to prevent oscillations.
The LT1763-X is a micropower device and output transient
response will be a function of output capacitance. Larger
values of output capacitance decrease the peak deviations
and provide improved transient response for larger load
current changes. Bypass capacitors, used to decouple
individual components powered by the LT1763-X, will
increase the effective output capacitor value. With larger
capacitors used to bypass the reference (for low noise
operation), larger values of output capacitors are needed.
For 100pF of bypass capacitance, 4.7μF of output capaci-
tor is recommended. With a 1000pF bypass capacitor or
larger, a 6.8μF output capacitor is recommended.
The shaded region of Figure 3 defi nes the range over
which the LT1763 regulators are stable. The minimum ESR
needed is defi ned by the amount of bypass capacitance
used, while the maximum ESR is 3Ω.
Extra consideration must be given to the use of ceramic
capacitors. Ceramic capacitors are manufactured with a
variety of dielectrics, each with different behavior across
temperature and applied voltage. The most common
dielectrics used are specifi ed with EIA temperature
characteristic codes of Z5U, Y5V, X5R and X7R. The Z5U
and Y5V dielectrics are good for providing high capacitances
in a small package, but they tend to have strong voltage
and temperature coeffi cients, as shown in Figures 4
and 5. When used with a 5V regulator, a 16V 10μF Y5V
capacitor can exhibit an effective value as low as 1μF to
2μF for the DC bias voltage applied and over the operating
temperature range. The X5R and X7R dielectrics result in
more stable characteristics and are more suitable for use
as the output capacitor. The X7R type has better stability
across temperature, while the X5R is less expensive and is
available in higher values. Care still must be exercised when
using X5R and X7R capacitors; the X5R and X7R codes
only specify operating temperature range and maximum
capacitance change over temperature. Capacitance change
due to DC bias with X5R and X7R capacitors is better than
16
Figure 5. Ceramic Capacitor Temperature Characteristics
Figure 4. Ceramic Capacitor DC Bias Characteristics
–100
–100
–20
–40
–60
–80
–20
–40
–60
–80
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
20
40
20
0
0
0
–50
0
1
C
BYP
BOTH CAPACITORS ARE 16V,
1210 CASE SIZE, 10μF
–25
2
= 0
C
BYP
OUTPUT CAPACITANCE (μF)
4
Figure 3. Stability
= 100pF
DC BIAS VOLTAGE (V)
0
2
TEMPERATURE (°C)
STABLE REGION
BOTH CAPACITORS ARE 16V,
1210 CASE SIZE, 10μF
6
25
C
3
BYP
8
Y5V
X5R
50
= 330pF
C
4
10
BYP
Y5V
75
5 6 7 8 9
12
1000pF
X5R
100
14
1763 F04
1763 F03
1763 F05
125
16
10
1763fg