KT
6860
1.5MHz, 500mA STEP-UP DC-DC CONVERTER
General Description
The KT6860 is a high power, constant frequency, cur-rent mode PWM, inductor based, step-up (boost) con-verter. The converter operates at high frequency
(1.5MHz) so that a small, low profile inductor can beused.
The KT6860 has built-in overvoltage protection (OVP)to allow the device goes into shutdown mode when theoutput voltage exceeds the OVP threshold of 29V. The KT6860 is available in standard SOT-23-5 pack-age.
Features
·········
High Efficiency up to 81%
Adjustable Output Voltage up to 29VShutdown Current 1µA Typical1.5MHz Switching Frequency
36V 500mA Rugged Integrated Bipolar SwitchBuilt-in Soft-start to Reduce Inrush Current Dur-ing Start-up
On-chip Overvoltage Protection
Uses Low ESR Ceramic Output Capacitor Uses Small Inductor
Applications
···
LCD/OLED Display Bias Supply
White LED Driver for LCD Display BacklightsCellular Phones
SOT-23-5
Figure 1. Package Type of KT6860
Aug. 2008Rev. 1. 4
1
www.kineteic.com
KT 68
60
Pin Configuration
(SOT-23-5)
SW GND FB
SHDN
V IN
K Package
Figure 2. Pin Configuration of KT6860 (Top View)
Pin Description
Pin Number
1
Pin NameSW
Function
Switch Pin. Connect inductor/diode here. The output voltage can go up to 29V but should notexceed this limit. If the voltage on this pin is higher than the overvoltage protection (OVP)threshold, the device can go into shutdown mode. It can be restarted by a low to high pulse onthe SHDN pin, or by a power on reset on the VIN supplyGround Pin. Connect directly to local ground plane
Feedback Pin. Internally compares to 1.25V. Connect R1 and R2 resistor divider here. Calcu-late the Output Voltage according to the formula: VOUT =1.25V * (1+R1/R2)
Shutdown Pin. Connect to 1.5V or higher to enable device (ON), 0.4V or lower to disabledevice (OFF)
Input Supply Pin. Must be locally bypassed
23
GND FB
45
SHDN V IN
Note: VOUT =1.25*(1+R1/R2)=1.25*19.2=24VC: X5R or X7R Dielectric
L: SUMIDA CDTH3D14/HPNP-100NC or Equivalent
Figure 12. LCD/OLED Display Bias Driver Typical Circuit
Aug. 2008Rev. 1. 4
2
www.kineteic.com
KT 6860
Functional Block Diagram
FB VIN
SHDN
Ordering Information
P
Package Type
K: SOT-23-5
Lead Free
G: Green
TR: Tape & Reel
Package
SOT-23-5
Temperature Range
-40 to 85o C
Part Number
Lead Free
Green
Marking ID
Lead Free
Green
Packing Type
KINETEIC's Pb-free products, as designated with "P" suffix in the part number, are RoHS compliant. Products with"G" suffix are available in green packages.
Aug. 2008Rev. 1. 4
3
www.kineteic.com
KT 6860
Absolute Maximum Ratings (Note 1)
Parameter Input Voltage SW Voltage FB Voltage SHDN Voltage
Thermal Resistance (Junction to Atmosphere, no Heat sink) Operating Junction TemperatureStorage Temperature RangeLead Temperature (Soldering, 10sec)ESD (Machine Model)ESD (Human Body Model)
Symbol V IN
Value 2038516
Unit V V V V
o
R θJA
265150
C/W
o o o
C C C
T STG T LEAD
-65 to [1**********]00
V V
Note 1: Stresses greater than those listed under "Absolute Maximum Ratings" may cause permanent damage tothe device. These are stress ratings only, and functional operation of the device at these or any other conditionsbeyond those indicated under "Recommended Operating Conditions" is not implied. Exposure to "Absolute Max-imum Ratings" for extended periods may affect device reliability.
Recommended Operating Conditions
ParameterInput Voltage Operating Temperature
Symbol V IN T OP
Min 2.6-40
Max 1685
Unit V
o
C
Aug. 2008Rev. 1. 4
4
www.kineteic.com
Electrical Characteristics
(VIN =3V, VSHDN , TA =25o C, unless otherwise specified.)
Parameter
Minimum Operating Volt-age
Maximum Operating Volt-age
Feedback Voltage FB Pin Bias CurrentSupply Current Supply Current Switching FrequencyMaximum Duty CycleSwitching Current LimitSwitch VCESATSwitch Leakage CurrentSHDN Voltage High (ON)SHDN V oltage Low (OFF)SHDN Pin Bias CurrentOVP Voltage ThresholdSoft-Start Time
V OVP V TH V TL
5529550
V CESAT I CC I Q f D MAX
Duty Cycle=80%I SW =250mAV SW =5V
1.5
0.4
V µA V µS
V FB
V IN =5V, VOUT =24V, IOUT =30mAV FB =1.25V
V SHDN =VFB =VIN , No switchingV SHDN =0V, VFB =0V
1.1851.1710
1.25452.50.11.5905003000.01
5
Symbol
Conditions
Min 2.6
161.331003.51.01.9
Typ
Max
Unit V V V nA mA µA MHz %mA mV µA
Aug. 2008Rev. 1. 4
5
www.kineteic.com
Typical Performance Characteristics
Figure 4. Quiescent Current vs. Input Voltage Figure 5. SHDN Pin Bias Current
vs. Junction Temperature
2.0S w i t c h i n g F r e q u e n c y (M H z )
1.6
1.2
0.8
0.4
0.0-50
-2502550
o
75100o
Junction Temperature (C) Junction Temperature (C)
Figure 6. Switching Frequency vs. Junction Temperature
Figure 7. Feedback Bias Current
vs. Junction Temperature
Aug. 2008Rev. 1. 4
6
www.kineteic.com
Typical Performance Characteristics (Continued)
Figure 8. Efficiency vs. Junction Temperature
Figure 9. Switching Current Limit vs. Duty Cycle
1.291.28
F e e d b a c k V o l t a g e
(V )
1.271.261.251.24
Figure 10. Feedback Voltage vs. Junction TemperatureFigure 11. Efficiency vs. Output Current
Aug. 2008Rev. 1. 4
7
www.kineteic.com
Mechanical Dimensions
SOT-23-5Unit: mm(inch)
Aug. 2008Rev. 1. 4
8
www.kineteic.com
KT
6860
1.5MHz, 500mA STEP-UP DC-DC CONVERTER
General Description
The KT6860 is a high power, constant frequency, cur-rent mode PWM, inductor based, step-up (boost) con-verter. The converter operates at high frequency
(1.5MHz) so that a small, low profile inductor can beused.
The KT6860 has built-in overvoltage protection (OVP)to allow the device goes into shutdown mode when theoutput voltage exceeds the OVP threshold of 29V. The KT6860 is available in standard SOT-23-5 pack-age.
Features
·········
High Efficiency up to 81%
Adjustable Output Voltage up to 29VShutdown Current 1µA Typical1.5MHz Switching Frequency
36V 500mA Rugged Integrated Bipolar SwitchBuilt-in Soft-start to Reduce Inrush Current Dur-ing Start-up
On-chip Overvoltage Protection
Uses Low ESR Ceramic Output Capacitor Uses Small Inductor
Applications
···
LCD/OLED Display Bias Supply
White LED Driver for LCD Display BacklightsCellular Phones
SOT-23-5
Figure 1. Package Type of KT6860
Aug. 2008Rev. 1. 4
1
www.kineteic.com
KT 68
60
Pin Configuration
(SOT-23-5)
SW GND FB
SHDN
V IN
K Package
Figure 2. Pin Configuration of KT6860 (Top View)
Pin Description
Pin Number
1
Pin NameSW
Function
Switch Pin. Connect inductor/diode here. The output voltage can go up to 29V but should notexceed this limit. If the voltage on this pin is higher than the overvoltage protection (OVP)threshold, the device can go into shutdown mode. It can be restarted by a low to high pulse onthe SHDN pin, or by a power on reset on the VIN supplyGround Pin. Connect directly to local ground plane
Feedback Pin. Internally compares to 1.25V. Connect R1 and R2 resistor divider here. Calcu-late the Output Voltage according to the formula: VOUT =1.25V * (1+R1/R2)
Shutdown Pin. Connect to 1.5V or higher to enable device (ON), 0.4V or lower to disabledevice (OFF)
Input Supply Pin. Must be locally bypassed
23
GND FB
45
SHDN V IN
Note: VOUT =1.25*(1+R1/R2)=1.25*19.2=24VC: X5R or X7R Dielectric
L: SUMIDA CDTH3D14/HPNP-100NC or Equivalent
Figure 12. LCD/OLED Display Bias Driver Typical Circuit
Aug. 2008Rev. 1. 4
2
www.kineteic.com
KT 6860
Functional Block Diagram
FB VIN
SHDN
Ordering Information
P
Package Type
K: SOT-23-5
Lead Free
G: Green
TR: Tape & Reel
Package
SOT-23-5
Temperature Range
-40 to 85o C
Part Number
Lead Free
Green
Marking ID
Lead Free
Green
Packing Type
KINETEIC's Pb-free products, as designated with "P" suffix in the part number, are RoHS compliant. Products with"G" suffix are available in green packages.
Aug. 2008Rev. 1. 4
3
www.kineteic.com
KT 6860
Absolute Maximum Ratings (Note 1)
Parameter Input Voltage SW Voltage FB Voltage SHDN Voltage
Thermal Resistance (Junction to Atmosphere, no Heat sink) Operating Junction TemperatureStorage Temperature RangeLead Temperature (Soldering, 10sec)ESD (Machine Model)ESD (Human Body Model)
Symbol V IN
Value 2038516
Unit V V V V
o
R θJA
265150
C/W
o o o
C C C
T STG T LEAD
-65 to [1**********]00
V V
Note 1: Stresses greater than those listed under "Absolute Maximum Ratings" may cause permanent damage tothe device. These are stress ratings only, and functional operation of the device at these or any other conditionsbeyond those indicated under "Recommended Operating Conditions" is not implied. Exposure to "Absolute Max-imum Ratings" for extended periods may affect device reliability.
Recommended Operating Conditions
ParameterInput Voltage Operating Temperature
Symbol V IN T OP
Min 2.6-40
Max 1685
Unit V
o
C
Aug. 2008Rev. 1. 4
4
www.kineteic.com
Electrical Characteristics
(VIN =3V, VSHDN , TA =25o C, unless otherwise specified.)
Parameter
Minimum Operating Volt-age
Maximum Operating Volt-age
Feedback Voltage FB Pin Bias CurrentSupply Current Supply Current Switching FrequencyMaximum Duty CycleSwitching Current LimitSwitch VCESATSwitch Leakage CurrentSHDN Voltage High (ON)SHDN V oltage Low (OFF)SHDN Pin Bias CurrentOVP Voltage ThresholdSoft-Start Time
V OVP V TH V TL
5529550
V CESAT I CC I Q f D MAX
Duty Cycle=80%I SW =250mAV SW =5V
1.5
0.4
V µA V µS
V FB
V IN =5V, VOUT =24V, IOUT =30mAV FB =1.25V
V SHDN =VFB =VIN , No switchingV SHDN =0V, VFB =0V
1.1851.1710
1.25452.50.11.5905003000.01
5
Symbol
Conditions
Min 2.6
161.331003.51.01.9
Typ
Max
Unit V V V nA mA µA MHz %mA mV µA
Aug. 2008Rev. 1. 4
5
www.kineteic.com
Typical Performance Characteristics
Figure 4. Quiescent Current vs. Input Voltage Figure 5. SHDN Pin Bias Current
vs. Junction Temperature
2.0S w i t c h i n g F r e q u e n c y (M H z )
1.6
1.2
0.8
0.4
0.0-50
-2502550
o
75100o
Junction Temperature (C) Junction Temperature (C)
Figure 6. Switching Frequency vs. Junction Temperature
Figure 7. Feedback Bias Current
vs. Junction Temperature
Aug. 2008Rev. 1. 4
6
www.kineteic.com
Typical Performance Characteristics (Continued)
Figure 8. Efficiency vs. Junction Temperature
Figure 9. Switching Current Limit vs. Duty Cycle
1.291.28
F e e d b a c k V o l t a g e
(V )
1.271.261.251.24
Figure 10. Feedback Voltage vs. Junction TemperatureFigure 11. Efficiency vs. Output Current
Aug. 2008Rev. 1. 4
7
www.kineteic.com
Mechanical Dimensions
SOT-23-5Unit: mm(inch)
Aug. 2008Rev. 1. 4
8
www.kineteic.com