INFINEON TLE8386-2EL

TLE8386-2EL
Basic Smart Boost Controller
Data Sheet
Rev. 1.0, 2010-10-25
Automotive Power
TLE8386-2EL
Table of Contents
Table of Contents
1
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2
Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3
3.1
3.2
Pin Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Pin Assignment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Pin Definitions and Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
4
4.1
4.2
4.3
General Product Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Functional Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Thermal Resistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5
5.1
5.2
Boost Regulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
6
6.1
6.2
Oscillator and Synchronization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
7
7.1
7.2
Enable Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
8
8.1
8.2
Linear Regulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
9
9.1
9.2
Protection and Diagnostic Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
10
10.1
10.1.1
10.1.2
10.2
10.2.1
10.2.2
Application Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Boost Converter Application Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Principle: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Component Selection: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Further Information on TLE8386-2EL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
General Layout recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Additional information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
11
Package Outlines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
12
Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Data Sheet
2
7
7
8
8
18
18
19
20
27
27
28
Rev. 1.0, 2010-10-25
Basic Smart Boost Controller
1
TLE8386-2EL
Overview
Features
•
•
•
•
•
•
•
•
•
•
•
•
Wide Input Voltage Range from 4.75 V to 45 V
Constant Current or Constant Voltage Regulation
Very Low Shutdown Current: Iq< 2µA
Flexible Switching Frequency Range, 100 kHz to 700 kHz
Synchronization with external clock source
Available in a small thermally enhanced PG-SSOP-14 package
Internal 5 V Low Drop Out Voltage Regulator
Output Overvoltage Protection
External Soft Start adjustable by capacitor
Over Temperature Shutdown
Automotive AEC Qualified
Green Product (RoHS) Compliant
PG-SSOP-14
Description
The TLE8386-2EL is a boost controller with built in protection features. The main function of this device is to stepup (boost) an input voltage to a larger output voltage. The switching frequency is adjustable from 100 kHz to
700 kHz and can be synchronized to an external clock source. The TLE8386-2EL features an enable function
reducing the shut-down current consumption to < 2 µA. The current mode regulation scheme of this device
provides a stable regulation loop maintained by small external compensation components. The integrated softstart feature with external components for adjustment limits the current peak as well as voltage overshoot at startup. This IC is suited for use in the harsh automotive environments and provides protection functions such as output
overvoltage protection and over temperature shutdown.
Type
Package
Marking
TLE8386-2EL
PG-SSOP-14
TLE8386-2EL
Data Sheet
3
Rev. 1.0, 2010-10-25
TLE8386-2EL
Block Diagram
2
Block Diagram
IN
14
LDO
13
FREQ
11
SYNC
10
On/Off
Logic
2
SWO
4
SWCS
3
SGND
6
FB
EN_INT
Power Switch
Gate Driver
Oscillator
Synchroni
sation
IVCC
Power On
Reset
Internal
Supply
EN
1
Slope
Comp.
PWM
Generator
Switch Current
Error Amplifier
Thermal
Protection
Leading Edge
Blanking
Over Voltage
Protection
SST
5
COMP
8
Soft Start
Feedback Voltage
Error Amplifier
TLE8386-2EL
12
B loc kDiagram.vs d
GND
Figure 1
Data Sheet
Block Diagram
4
Rev. 1.0, 2010-10-25
TLE8386-2EL
Pin Configuration
3
Pin Configuration
3.1
Pin Assignment
,9&&
,1
6:2
(1
6*1'
*1'
6:&6
)5(4
667
6<1&
)%
1&
1&
&203
SLQFRQILJBVVRSVYJ
Figure 2
Pin Configuration
3.2
Pin Definitions and Functions
Pin
Symbol
Function
1
IVCC
Internal LDO Output;
Used for internal biasing and gate drive. Do not leave open, bypass with external
capacitor. Do not connect other circuitry to this pin.
2
SWO
Switch Output;
Connect to the gate of external boost converter switching MOSFET.
3
SGND
Current Sense Ground;
Ground return for current sense switch, connect to bottom side of sense resistor.
4
SWCS
Current Sense Input;
Detects the peak current through switch, connect to high side of sense resistor.
5
SST
Soft Start;
Connect an external capacitor to adjust the soft start ramp, do not leave open.
6
FB
Feedback;
Output voltage feedback, connect to output voltage via resistor divider from output
capacitor to ground.
7
NC
Not Connected;
8
COMP
Compensation Input;
Connect R and C network to improve the stability of the regulation loop.
Data Sheet
5
Rev. 1.0, 2010-10-25
TLE8386-2EL
Pin Configuration
Pin
Symbol
Function
9
NC
Not Connected;
10
SYNC
Sync;
Synchronization Input, if feature synchronization is not used, leave open.
11
FREQ
Frequency Select Input;
Connect external resistor to GND to set frequency, do not leave open.
12
GND
Ground;
Connect to system ground.
13
EN
Enable;
Apply logic high signal to enable device.
14
IN
Supply Input;
Supply for internal biasing, connect to input voltage.
Exposed Pad
Data Sheet
Connect to GND.
6
Rev. 1.0, 2010-10-25
TLE8386-2EL
General Product Characteristics
4
General Product Characteristics
4.1
Absolute Maximum Ratings
Absolute Maximum Ratings1)
Tj = -40 °C to +150 °C; all voltages with respect to ground, positive current flowing into pin
(unless otherwise specified)
Pos.
Parameter
Symbol
Limit Values
Min.
Max.
Unit
Conditions
Voltages
4.1.1
IN
Supply Input
VIN
-0.3
45
V
4.1.2
EN
Enable Input
VEN
-40
45
V
4.1.3
FB;
Feedback Error Amplifier Input
VFB
-0.3
5.5
V
-0.3
6.2
V
SWCS
Switch Current Sense Input
VSWCS
-0.3
5.5
V
-0.3
6.2
V
SWO
Switch Gate Drive Output
VSWO
-0.3
5.5
V
-0.3
6.2
V
4.1.9
SGND
Current Sense Switch GND
VSGND
-0.3
0.3
V
4.1.10
VCOMP
-0.3
5.5
V
4.1.11
COMP
Compensation Input
-0.3
6.2
V
4.1.12
FREQ; Frequency Input
VFREQ
-0.3
5.5
V
-0.3
6.2
V
SYNC; Synchronization Input
VSYNC
-0.3
5.5
V
-0.3
6.2
V
-0.3
5.5
V
-0.3
6.2
V
-0.3
5.5
V
-0.3
6.2
V
t < 10s
-40
150
°C
–
-55
150
°C
–
4.1.4
4.1.5
4.1.6
4.1.7
4.1.8
4.1.13
4.1.14
4.1.15
4.1.16
SST; Softstart Setting Input
VSST
4.1.17
4.1.18
4.1.19
IVCC
VIVCC
Internal Linear Voltage Regulator Output
t < 10s
t < 10s
t < 10s
t < 10s
t < 10s
t < 10s
t < 10s
Temperatures
4.1.20
Junction Temperature
4.1.21
Storage Temperature
Data Sheet
Tj
Tstg
7
Rev. 1.0, 2010-10-25
TLE8386-2EL
General Product Characteristics
Absolute Maximum Ratings1)
Tj = -40 °C to +150 °C; all voltages with respect to ground, positive current flowing into pin
(unless otherwise specified)
Pos.
Parameter
Symbol
Limit Values
Unit
Conditions
Min.
Max.
-2
2
kV
HBM2)
-500
500
V
CDM3)
-750
750
V
CDM3)
ESD Susceptibility
4.1.22
ESD Resistivity to GND
4.1.23
ESD Resistivity to GND
4.1.24
ESD Resistivity Pin 1, 7, 8, 14 (corner
pins) to GND
VESD,HBM
VESD,CDM
VESD,CDM,C
1) Not subject to production test, specified by design.
2) ESD susceptibility, Human Body Model “HBM” according to EIA/JESD 22-A114B
3) ESD susceptibility, Charged Device Model “CDM” EIA/JESD22-C101 or ESDA STM5.3.1
Note: Stresses above the ones listed here may cause permanent damage to the device. Exposure to absolute
maximum rating conditions for extended periods may affect device reliability.
Note: Integrated protection functions are designed to prevent IC destruction under fault conditions described in the
data sheet. Fault conditions are considered as “outside” normal operating range. Protection functions are
not designed for continuous repetitive operation.
4.2
Pos.
4.2.1
Functional Range
Parameter
Symbol
Supply Voltage Input
VIN
Limit Values
Min.
Max.
4.75
45
Unit
Conditions
V
VIVCC > VIVCC,RTH,d
Note: Within the functional range the IC operates as described in the circuit description. The electrical
characteristics are specified within the conditions given in the related electrical characteristics table.
4.3
Thermal Resistance
Note: This thermal data was generated in accordance with JEDEC JESD51 standards. For more information, go
to www.jedec.org.
Pos.
4.3.1
4.3.2
Parameter
Symbol
1)
Junction to Case
Junction to Ambient
4.3.3
4.3.4
1) 2)
RthJC
RthJA
RthJA
RthJA
Limit Values
Unit
Conditions
Min.
Typ.
Max.
–
10
–
K/W
–
–
47
–
K/W
2s2p
–
54
–
K/W
1s0p + 600 mm2
–
64
–
K/W
1s0p + 300 mm2
1) Not subject to production test, specified by design.
2) Specified RthJA value is according to JEDEC 2s2p (JESD 51-7) + (JESD 51-5) and JEDEC 1s0p (JESD 51-3) + heatsink
area at natural convection on FR4 board;
Data Sheet
8
Rev. 1.0, 2010-10-25
TLE8386-2EL
Boost Regulator
5
Boost Regulator
5.1
Description
The TLE8386-2 boost (step-up) regulator provides a higher output voltage than input voltage. The PWM controller
measures the output voltage via a resistor divider connected between Pin FB and ground, and determines the
appropriate pulse width duty cycle (on time). An over voltage protection switches off the converter case if the
voltage at Pin FB exceeds the over voltage limit. If the connection to the output voltage resistor divider should be
lost, an internal current source connected to Pin FB will draw the voltage above this limit and shut the external
MOSFET off. The current mode controller has a built-in slope compensation to prevent sub-harmonic oscillations
which is a characteristic of current mode controllers operating at high duty cycles (>50% duty). An additional builtin feature is an integrated soft start that limits the current through the inductor and the external power switch during
initialization.
The soft-start time TSS is adjustable using an external capacitor CSST:
2 ,00V
T SS = C SST × --------------10µA
The switching frequency may be adjusted by using an external resistor (please refer to chapter Oscillator and
Synchronization). If synchronization to an external frequency source is used, the internal frequency has to be
adjusted close to this external source.
VIVCC
SYNC
10
Synchroni
zation
S
FREQ
11
Temp.
Sensor
R
Slope
Comp.
2
SWO
Current Sense
OTA
+
4
SWCS
-
3
SGND
6
FB
D
Q
Oscillator
/Q
Gate
Driver
Logic
Soft
Start
Over Voltage
Comparator
PWM Curr
Comparator
VOVFB,TH
Soft Start
SST
5
gmEA
COMP
Feedback Error
Amplifier
8
VRef
Boost_Diag .vsd
Figure 3
Data Sheet
Boost Regulator Block Diagram
9
Rev. 1.0, 2010-10-25
TLE8386-2EL
Boost Regulator
5.2
Electrical Characteristics
1)
VIN = 6V to 40V; Tj = -40 °C to +150 °C, all voltages with respect to ground, positive current flowing into pin; (unless
otherwise specified)
Pos.
Parameter
Symbol
Limit Values
Min.
Typ.
Max.
Unit
Conditions
VIN = 19 V;
IBO = 100 to 500 mA
VIN = 6 to 19 V;
VBO= 30 V;
IBO = 100 mA
Boost Regulator:
5.2.1
Feedback Reference Voltage
VFB
2.32.
2.5
2.62
V
5.2.2
Voltage Line Regulation
∆VREF
/∆VIN
–
–
0.15
%/V
Figure 8
5.2.3
Voltage Load Regulation
∆VFB
/∆IBO
–
–
5
%/A
VIN = 13V;
VBO = 30V;
IBO = 100 to 500 mA
Figure 8
5.2.4
Switch Peak Over Current
Threshold
VSWCS
120
150
180
mV
5.2.5
Current to Softstart setting
Capacitor
ISST
-8
-10
-16
µA
5.2.6
Feedback Input Current
5.2.7
Switch Current Sense Input
Current
IFB
ISWCS
5.2.8
Input Undervoltage Shutdown
5.2.9
Input Voltage Startup
-200
VIN = 6 V
VFB < VFBOV
VCOMP = 3.5V
nA
-10
-50
-100
µA
VSWCS = 150 mV
VIN,off
VIN,on
3.75
–
–
V
–
–
4.75
V
VIN decreasing
VIN increasing
Gate Driver for Boost Switch
5.2.10
Gate Driver Peak Sourcing
Current1)
ISWO,SRC
–
-380
–
mA
VSWO = 3.5V
5.2.11
Gate Driver Peak Sinking
Current1)
ISWO,SNK
–
550
–
mA
VSWO = 1.5V
5.2.12
Gate Driver Output Rise Time
tR,SWO
–
30
60
ns
5.2.13
Gate Driver Output Fall Time
tF,SWO
–
20
40
ns
5.2.14
Gate Driver Output Voltage1)
VSWO
4.5
–
5.5
V
CL,SWO = 3.3nF;
VSWO = 1V to 4V
CL,SWO = 3.3nF;
VSWO = 1V to 4V
CL,SWO = 3.3nF;
1) Not subject to production test, specified by design
Data Sheet
10
Rev. 1.0, 2010-10-25
TLE8386-2EL
Boost Regulator
Efficiency depending on
Input Voltage VIN and output Current IBO
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Data Sheet
11
Rev. 1.0, 2010-10-25
TLE8386-2EL
Boost Regulator
Load regulation
Input Voltage VIN = 6V
Load regulation
Input Voltage VIN = 13.5
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/RDG5HJXODWLRQYV7HPS$,RXW$
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7HPSƒ&
Load regulation
Input Voltage VIN = 19V
/RDG5HJXODWLRQYV7HPS$,RXW$
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Data Sheet
12
Rev. 1.0, 2010-10-25
TLE8386-2EL
Oscillator and Synchronization
6
Oscillator and Synchronization
6.1
Description
R_OSC vs. switching frequency
The internal oscillator is used to determine the switching frequency of the boost regulator. The switching frequency
can be selected from 100 kHz to 700 kHz with an external resistor to GND. To set the switching frequency with an
external resistor the following formula can be applied.
R FREQ =
1
(141 × 10 [ ])× ( f
− 12
s
Ω
FREQ
[1s ])
(
) [Ω ]
− 3 . 5 × 10 3 [Ω ]
In addition, the oscillator is capable of changing from the frequency set by the external resistor to a synchronized
frequency from an external clock source. If an external clock source is provided on the pin SYNC, the internal
oscillator should adjusted close to this frequency. Then it synchronizes to this external clock frequency and the
boost regulator switches at the synchronized frequency. The synchronization frequency capture range is from 250
kHz to 700 kHz.
TLE8386-2EL
SYNC
Clock Frequency
Detector
FREQ
Multiplexer
Oscillator
PWM
Logic
Gate
Driver
SWO
VCLK
R FREQ
Oscillator_BlkDiag.vsd
Figure 4
Oscillator and Synchronization Block Diagram and Simplified Application Circuit
76<1& I6<1&
96<1&
W6<1&75
W6<1&75
W6<1&3:+
9
96<1&+
9
96<1&/
W
2VFLOODWRUB7LPLQJVYJ
Figure 5
Data Sheet
Synchronization Timing Diagram
11
Rev. 1.0, 2010-10-25
TLE8386-2EL
Oscillator and Synchronization
6.2
Electrical Characteristics
VIN = 6V to 40V; Tj = -40 °C to +150 °C, all voltages with respect to ground, positive current flowing into pin; (unless
otherwise specified)
Pos.
Parameter
Symbol
Limit Values
Unit
Conditions
Min.
Typ.
Max.
fFREQ
fFREQ
250
300
350
kHz
RFREQ = 20kΩ
100
–
700
kHz
17% internal tolerance +
external resistor
tolerance
IFREQ
–
–
-700
µA
VFREQ = 0 V
Oscillator:
6.2.1
Oscillator Frequency
6.2.2
Oscillator Frequency
Adjustment Range
6.2.3
FREQ Supply Current
Synchronization
6.2.4
SYNC input internal pulldown
RSYNC
150
250
350
kΩ
VSYNC= 5V
6.2.5
Maximum Duty Cycle
90
93
95
%
Fixed frequency mode
6.2.6
Maximum Duty Cycle
DMAX,fixed
DMAX,sync
88
–
–
%
Synchronization mode,
ratio between
synchronization and
internal frequency (set
by resistor) is 0.8 to 1.2
6.2.7
Synchronization Frequency
Capture Range
fSYNC
250
–
700
kHz
ratio between
synchronization and
internal frequency (set
by resistor) is 0.8 to 1.2
6.2.8
Synchronization Signal Duty TD_SYNC
cycle
20
80
%
6.2.9
Synchronization Signal
High Logic Level Valid
VSYNC,H
3.0
–
–
V
1)
6.2.10
Synchronization Signal
Low Logic Level Valid
VSYNC,L
–
–
0.8
V
1)
1) Synchronization of external SWO ON signal to falling edge
Data Sheet
12
Rev. 1.0, 2010-10-25
TLE8386-2EL
Oscillator and Synchronization
Typical Performance Characteristics of Oscillator
Switching Frequency fSW versus
Frequency Select Resistor to GND RFREQ
fFREQ [kHz]
700
600
500
400
Tj = 25 °C
300
200
100
0
0
10 20
30
40
50
60
70
80
RFREQ [kohm]
Oscillator_fFreq_vs_Rfreq.vsd
Data Sheet
13
Rev. 1.0, 2010-10-25
TLE8386-2EL
Enable Function
7
Enable Function
7.1
Description
The enable function powers on or off the device. A valid logic low signal on enable pin EN powers off the device
and current consumption is less than 2 µA. A valid logic high enable signal on enable pin EN powers on the device.
The Enable Startup Time tEN,START is the time between the Enable signal is recognized as valid and the device
starts to switch. During this period of time the internal supplies, bandgap are initalized and reach their nominal
values. The TLE8386-2 will start to switch after the nominal values are reached.
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Data Sheet
Timing Diagram Enable
14
Rev. 1.0, 2010-10-25
TLE8386-2EL
Enable Function
7.2
Electrical Characteristics
VIN = 6V to 40V; Tj = -40 °C to +150 °C, all voltages with respect to ground, positive current flowing into pin; (unless
otherwise specified)
Pos.
Parameter
Symbol
Limit Values
Min.
Typ.
Unit
Conditions
V
–
Max.
Enable Input:
7.2.1
Enable
Turn On Threshold
VEN,ON
3.0
–
7.2.2
Enable
Turn Off Threshold
VEN,OFF
–
–
0.8
V
–
7.2.3
Enable Hysteresis
200
400
mV
–
Enable
High Input Current
VEN,HYS
IEN,H
50
7.2.4
–
–
30
µA
VEN = 16.0 V
7.2.5
Enable
Low Input Current
IEN,L
–
0.1
1
µA
VEN = 0.5 V
7.2.6
Enable Startup Time1)
tEN,START
100
–
–
µs
–
VEN = 0.8 V;
Tj ≤ 105C; VIN = 16V
VEN ≥ 4.75 V;
IBO = 0 mA;
VIN = 16V
VSWO = 0% Duty
Current Consumption
7.2.7
Current Consumption,
Shutdown Mode
Iq_off
–
–
2
µA
7.2.8
Current Consumption,
Active Mode2)
Iq_on
–
–
7
mA
1) Not subject to production test, specified by design.
2) Dependency on switching frequency and gate charge of boost.
Data Sheet
15
Rev. 1.0, 2010-10-25
TLE8386-2EL
Linear Regulator
8
Linear Regulator
8.1
Description
The internal linear voltage regulator supplies the internal gate drivers with a typical voltage of 5 V and current up
to 50 mA. An external output capacitor with low ESR is required on pin IVCC for stability and buffering transient
load currents. During normal operation the external boost MOSFET switch will draw transient currents from the
linear regulator and its output capacitor. Proper sizing of the output capacitor must be considered to supply
sufficient peak current to the gate of the external MOSFET switch. Please refer to application section for
recommendations on sizing the output capacitor. An integrated power-on reset circuit monitors the linear regulator
output voltage and resets the device in case the output voltage falls below the power-on reset threshold. The
power-on reset helps protect the external switches from excessive power dissipation by ensuring the gate drive
voltage is sufficient to enhance the gate of an external logic level n-channel MOSFET.
IVCC stays at around 300 mV when Enable signal is off. No external circuit should be connected to IVCC
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Figure 7
Voltage Regulator Block Diagram and Simplified Application Circuit
8.2
Electrical Characteristics
VIN = 6V to 40V; Tj = -40 °C to +150 °C, all voltages with respect to ground, positive current flowing into pin; (unless
otherwise specified)
Pos.
Parameter
Symbol
Limit Values
Unit
Conditions
5.4
V
6 V ≤ VIN ≤ 45 V
0.1 mA ≤ IIVCC ≤ 50 mA
110
mA
VIN = 13.5 V
VIVCC = 4.5V
IIVCC = 50mA 1)
Min.
Typ.
Max.
5
8.2.1
Output Voltage
VIVCC
4.6
8.2.2
Output Current Limitation
ILIM
51
8.2.6
VDR
CIVCC
0.47
Output Capacitor ESR
RIVCC,ESR
Undervoltage Reset Headroom VIVCC,HDRM 100
–
–
mV
8.2.7
Undervoltage Reset Threshold VIVCC,RTH,d
4.0
–
–
V
8.2.8
Undervoltage Reset Threshold VIVCC,RTH,i
–
–
4.5
V
8.2.3
8.2.4
8.2.5
Drop out Voltage
1000
mV
Output Capacitor
3
µF
2)
0.5
Ω
f = 10kHz
VIVCC decreasing
VIVCC - VIVCC,RTH,d
VIVCC decreasing
VIVCC increasing
1) Measured when the output voltage VCC has dropped 100 mV from its nominal value.
2) Minimum value given is needed for regulator stability; application might need higher capacitance than the minimum.
Data Sheet
16
Rev. 1.0, 2010-10-25
TLE8386-2EL
Protection and Diagnostic Functions
9
Protection and Diagnostic Functions
9.1
Description
The TLE8386-2EL has integrated circuits to protect against output overvoltage, open feedback and
overtemperature faults. During an overvoltage the gate driver outputs SWO will turn off. In the event of an
overtemperature condition the integrated thermal shutdown function turns off the gate drivers and internal linear
voltage regulator. If the connection from pin FB to the output voltage resistor divider should be lost, an internal
current source connected to Pin FB will draw the voltage above this limit and shut the external MOSFET off. The
typical junction shutdown temperature is 175°C. After cooling down the IC will automatically restart operation.
Thermal shutdown is an integrated protection function designed to prevent immediate IC destruction and is not
intended for continuous use in normal operation.
9.2
Electrical Characteristics
VIN = 6V to 40V; Tj = -40 °C to +150 °C, all voltages with respect to ground, positive current flowing into pin; (unless
otherwise specified)
Pos.
Parameter
Symbol
Limit Values
Min.
Unit
Conditions
Typ.
Max.
Tj,SD
160
Tj,SD,HYST –
175
190
°C
–
15
–
°C
–
10
12
%
10% higher of
regulated voltage
%
Output Voltage
decreasing
µs
Output Voltage
decreasing
Temperature Protection:
9.2.1
Over Temperature Shutdown
9.2.2
Over Temperature Shutdown
Hystereses
Overvoltage Protection:
9.2.3
Output Over Voltage Feedback
Threshold Increasing
VOVFB,TH
9.2.4
Output Over Voltage Feedback
Hysteresis
VOVFB,HYS
9.2.5
Over Voltage Reaction Time
tOVPRR
8
5
2
–
10
Note: Integrated protection functions are designed to prevent IC destruction under fault conditions described in the
data sheet. Fault conditions are considered as “outside” normal operating range. Protection functions are
not designed for continuous repetitive operation.
Data Sheet
17
Rev. 1.0, 2010-10-25
TLE8386-2EL
Application Information
10
Application Information
Note: The following information is given as a hint for the implementation of the device only and shall not be
regarded as a description or warranty of a certain functionality, condition or quality of the device.
10.1
Boost Converter Application Circuit
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Figure 8
Boost Converter Application Circuit
Reference
Designator
Value
Manufacturer
Part Number
Type
Quantity
DBOOST
Schottky, 3 A, 100 VR
Vishay
SS3H10
Diode
1
COUT
100 uF, 80V
Panasonic
EEVFK1K101Q
Capacitor
1
CIN1
100 uF, 50V
Panasonic
EEEFK1H101GP
Capacitor
1
CCOMP
10 nF
--
--
Capacitor
1
CIVCC
100 uF, 6.3V
Panasonic
EEFHD0J101R
Capacitor
1
IC1
--
Infineon
TLE8386-2EL
IC
1
LBOOST
100 uH
Coilcraft
MSS1278T-104ML_
Inductor
1
RCOMP
10 kΩ
Panasonic
ERJ3EKF1002V
Resistor
1
RFBH
11 kΩ, 1%
Panasonic
ERJ3EKF1102V
Resistor
1
RFBL
1 kΩ, 1%
Panasonic
ERJ3EKF1001V
Resistor
1
RFREQ
20 kΩ, 1%
Panasonic
ERJ3EKF2002V
Resistor
1
RCS
50 mΩ, 1%
Panasonic
ERJB1CFR05U
Resistor
1
CSST
4,7 nF
--
--
Capacitor
1
Figure 9
Boost Application Circuit Bill of Material
Note: This is a simplified example of an application circuit. The function must be verified in the real application.
Data Sheet
18
Rev. 1.0, 2010-10-25
TLE8386-2EL
Application Information
10.1.1
Principle:
The TLE8386-2EL can be configured as a boost converter, where the desired output voltage VBO is always higher
than the input voltage VIN. A boost convertor is not short-circuit protected. If the output voltage VBO is shorted, the
output current will only be limited by the input voltage VIN capability.
A typical boost converter application is shown in Figure 8, the elements and abbreviations and their meanings are:
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
LBOOST = boost inductor
LINPUT = input filter inductor, recommended to reduce electromagnetic emissions
CIN1 = input filter capacitor
CIN2 = additional input filter capacitor, recommended to reduce electromagnetic emissions
COUT = output filter capacitor
DBOOST = output diode
VIN = input voltage
VINMIN = minimum input voltage
VBO = boost output voltage
RCS = current sense resistor
RFBH = boost output voltage resistor divider, highside resistor
RFBL = boost output voltage resistor divider, lowside resistor
RCOMP, CCOMP = compensation network elements
RFREQ = frequency setting resistor
CSST = softstart setting capacitor
CIVCC = capacitor for internal LDO
D = duty cycle
DMAX = maximum duty cycle
fFREQ = Switching Frequency
IIN = input current
IBO = output current
IBOMAX = maximum output current
The ratio between input voltage VIN and output voltage VBO in continuos conduction mode (CCM) is:
V BO
V BO – V IN
1
----------- = ------------- ⇔ D = ------------------------1–D
V IN
V BO
In discontinous conduction mode (DCM) the conversion ratio at a fixed frequency is higher, the switching current
increases and efficiency is reduced. The maximum duty cycle DMAX occurs for minimum input voltage VINMIN.
Data Sheet
19
Rev. 1.0, 2010-10-25
TLE8386-2EL
Application Information
10.1.2
Component Selection:
Power MOSFET selection:
The important parameters for the choice of the power MOSFET are:
•
•
•
•
•
Drain-source voltage rating VDS: The power MOSFET will see the full output voltage VBO plus the output diode
(DBOOST) forward voltage. During its off-time additional ringing across drain-to-source will occur.
On-resistance RDSON for efficiency reasons and power dissipation
Maximum drain current IDMAX
Gate-to-source charge and gate-to-drain charge
Thermal resistance
It is recommended to choose a power MOSFET with a drain-source voltage rating VDS of at least 10 V higher than
the output voltage VBO.
The power dissipation PLOSSFET in the power MOSFET can be calculated using the following formula:
•
•
CRSS = reverse transfer capacitance, please refer to power MOSFET data sheet
IBOOSTMAX = maximum average current through the boost inductor LBOOST.
f FREQ
2
2
P LOSSFET = I BOOSTMAX × R DSON + 2 × V BO × I BOOSTMAX × C RSS × -------------1A
The first term in the equation above gives the conduction losses in the power MOSFET, the second term the
switching losses. To optimize the efficiency, RDSON and CRSS should be minimized.
Data Sheet
20
Rev. 1.0, 2010-10-25
TLE8386-2EL
Application Information
Current sense resistor RCS selection:
For control and protection, the TLE8386-2EL measures the power MOSFET current by a current sense resistor
RCS, which is located between the power MOSFET source and ground. For proper function it is very important:
•
•
•
•
•
To locate the current sense resistor as close as possible to the TLE8386-2EL
To use short (low resistive and low inductive) traces between the power MOSFET source and ground.
To use short (low resistive and low inductive) traces between the current sense resistor RCS highside and
lowside and the pins SWCS and SGND (it is not recommended to use pin GND instead of pin SGND for power
MOSFET current measurement).
The value of RCS should be selected to make sure that the maximum peak sense voltage VSENSEPEAK during
steady state normal operation will be lower than the adjusted current limit threshold (current limit function!). It
is recommended to give a 20% margin.
The value of RCS should be selected to make sure that the power MOSFET maximum drain current IDMAX will
not be exceeded (please refer to power MOSFET data sheet).
The figure below shows the voltage waveform over the current sense resistor RCS during a switching cycle:
VSENSE
∆VSENSE
VSENSEMAX
VSENSEPEAK
t
On-Time
Switching Cycle
Figure 10
•
•
•
Sense voltage VSENSE waveform during a switching cycle
VSENSEMAX = maximum average sense voltage at maximum output current IBO measured during on-time.
VSENSEPEAK = maximum peak sense voltage at maximum output current IBO at end of on-time.
∆VSENSE = ripple voltage across RCS (switch ripple current) during on-time, represents the peak-to-peak ripple
current in the boost inductor LBOOST.
The maximum (peak-to-peak) switch current ripple percentage χ (will be needed for further calculations of inductor
values) can be calculated considering the 20% margin by following equation:
∆V SENSE
χ = -------------------------------------------------------------------------------0 ,80 × V SWCS – 0 ,50 × ∆V SENSE
•
•
VSWCS = Switch peak over current threshold
χ is recommended to fall in the range between 0.2 to 0.6 (please refer to calculations in the following chapters)
Data Sheet
21
Rev. 1.0, 2010-10-25
TLE8386-2EL
Application Information
The value of the sense resistor RCS can be calculated as follows:
0 ,80 × V SWCS
R CS = --------------------------------I BOOSTPEAK
•
IBOOSTPEAK = peak current through the boost inductor LBOOST (will be calculated at boost inductor selection)
Boost inductor LBOOST selection:
The important parameters for selecting the boost inductor are:
•
•
•
Inductor LBOOST
Maximum RMS current rating IBOOSTRMS for thermal design
Saturation current threshold IBOOSTSAT
The maximum average inductor current is:
1
I BOOSTMAX = I BOMAX × -----------------------1 – D MAX
The ripple current through the boost inductor is:
1
∆I BOOST = χ × I BOOSTMAX = χ × I BOMAX × -----------------------1 – D MAX
The peak current through the boost inductor is:
I BOOSTPEAK = I BOOSTMAX ×  1 + χ
--- < I BOOSTSAT

2
(The peak current trough the boost inductor must be smaller than the saturation current threshold!)
The RMS current through the boost inductor is:
2
I BOOSTRMS
χ= I BOOSTMAX × 1 + ----12
The boost inductor value LBOOST can be calculated by the following equation:
V INMIN
L BOOST = ------------------------------------------ × D MAX
∆I BOOST × f FREQ
Data Sheet
22
Rev. 1.0, 2010-10-25
TLE8386-2EL
Application Information
In fixed frequency mode an external resistor determines the switching frequency. The minimum boost inductor for
fixed frequency is given by the formula below:
•
LBOOSTMIN = minimum Inductance required (minimum value of LBOOST)
V BO [ V ] × R CS [ Ω ]
L BOOSTMIN ≥ ----------------------------------------------------------------–3
106 ×10 [ V ] × f FREQ [ Hz ]
Following the previous equations the user should choose the boost inductor having sufficient saturation and RMS
current ratings.
The boost inductor value influences the current ripple ∆IBOOST:
•
•
A larger boost inductor value decreases the current ripple ∆IBOOST, but reduces also the current loop gain.
A lower boost inductor value increases the current ripple ∆IBOOST, but provides faster transient response. A
lower boost inductor value also results in higher input current ripple and greater core losses.
Output diode DBOOST selection:
Guidelines to choose the diode:
•
•
•
•
Fast switching diode
Low forward drop
Low reverse leakage current
It is recommended to choose the repetitive reverse voltage rating VRRM (please refer to diode data sheet) at
least 10V higher than the boost converter output voltage VBO.
The average forward current in normal operation is equal to the boost converter output current IBO and the peak
current through the diode IDPEAK (occurs in off-time of the power MOSFET) is:
I DPEAK = I BOOSTPEAK = I BOOSTMAX ×  1 + χ
---

2
The power dissipation PLOSSDIO in the output diode DBOOST is:
P LOSSDIO = I BOMAX × V D
•
VD = forward drop voltage of diode DBOOST (please refer to diode data sheet).
Data Sheet
23
Rev. 1.0, 2010-10-25
TLE8386-2EL
Application Information
Output filter capacitor COUT selection:
Choosing the correct output capacitor for given output ripple voltage, the influence of
•
•
•
ESR = equivalent series resistance,
ESL = equivalent series inductance and
bulk capacitance have to be considered.
The effects of these three parameters is additional ringing on the output voltage VBO.
The voltage ripple at the output voltage VBO depends on:
•
•
•
∆VESR: in percent, related to the ESR of the output capacitor(s)
∆VCOUT: in percent, related to the bulk capacitance of the output capacitor(s)
To receive the total voltage ripple, the influence of ∆VESR and ∆VCOUT must be counted together.
The output capacitor can be calculated using the following equation (which contains the influence of the bulk
capacitance on the output voltage ripple):
I BOMAX
C OUT ≥ --------------------------------------------------------------∆V COUT × V OUT × f FREQ
Influence of the capacitor ESR on the output voltage ripple:
∆V ESR
ESR COUT ≤ -----------------I DPEAK
The output capacitor experiences high RMS ripple currents, the RMS ripple current rating can be determined using
the following formula:
D MAX
I COUTRMS ≥ I BOMAX × ----------------------1 – D MAX
•
ICOUTRMS = RMS ripple current rating at switching frequency IFREQ.
To meet the ESR requirements often multiple capacitors are paralleled. Typically, once the ESR requirement is
met, the output capacitance is adequate for filtering and has the required RMS current rating. Additional ceramic
capacitors are commonly used to reduce the effects of parasitic inductance to reduce high frequent switching
noise on the boost converter output.
Data Sheet
24
Rev. 1.0, 2010-10-25
TLE8386-2EL
Application Information
Input filter capacitor CIN1 selection:
The input filter capacitor CIN1 has to compensate the alternate current content or current ripple on the input line,
recommended values are from 10µF to 100µF, to improve the suppression of high frequent distortions a parallel
ceramic capacitor might be necessary.
The RMS input capacitor ripple current IIN1RMS for a boost converter is:
I IN1RMS = 0 ,30 × ∆I BOOST
Compensation network elements RCOMP, CCOMP selection:
To compensate the feedback loop of the TLE8386-2EL a series network of RCOMP, CCOMP is usually connected from
pin COMP to ground. For most applications the capacitor CCOMP should be in the range of 470pF to 22nF, and the
resistor RCOMP should be in the range of 5kΩ to 100kΩ. An additional capacitor CCOMP2 might be usefull to improve
stability. CCOMP and CCOMP2 should be a low ESR ceramic capacitors.
A practical approach to determine the compensation network is to start with the application circuit as shown in the
data sheet and tune the compensation network to optimize the performance. Stability of the loop should then be
checked under all operating conditions, including output current and variations and over the entire temperature
range.
Output boost voltage VBO adjustment by determining the output voltage resistor divider RFBH, RFBL:
•
VFB = feedback reference voltage
R FBH + R FBL
V BO = V FB × -------------------------------R FBL
(VBO is always higher than VIN during operation of the boost converter)
Additional input filter inductor LINPUT and capacitor CIN2 selection:
•
fFILTER = resonance frequency of the additional input filter
The input filter inductor LINPUT should have a saturation current value equal to LBOOST, capacitor CIN2 should be a
low ESR ceramic capacitor. Both elements are forming a low pass filter to suppress conducted disturbances on
the VIN line. To obtain an optimum suppression, the input filter resonance frequency fFILTER should be at least ten
times lower than the switching frequency fFREQ:


1
f FREQ > 10 ×  f FILTER = ------------------------------------------------

2Π L INPUT × C IN2
The use of an additional input filter is depending on the requirements of the application.
For selection of RFREQ, CSST and CIVCC please refer to previous chapters.
Data Sheet
25
Rev. 1.0, 2010-10-25
TLE8386-2EL
Application Information
10.2
Further Information on TLE8386-2EL
10.2.1
General Layout recommendations
Introduction:
A boost converter is a potential source of electromagnetic disturbances which may affect the environment as well
as the device itself and cause sporadic malfunction up to damages depending on the amount of noise.
In principal we may consider the following basic effects:
•
•
•
Radiated magnetic fields caused by circular currents, occurring mostly with the switching frequency and their
harmonics
Radiated electric fields, often caused by (voltage) oscillations
Conducted disturbances (voltage spikes or oscillations) on the lines, mostly input and output lines.
Radiated magnetic fields:
Radiated magnetic fields are caused by circular currents occurring in so called “current windows”. These circular
currents are alternating currents which are driven by the switching transistor. The alternating current in these
windows are driving magnetic fields. The amount of magnetic emissions is mostly depending on the amplitude of
the alternating current and the size of the so-called “window” (this is the area, which is defined by the circular
current paths. We can divide into two windows:
•
•
the input current “window” (path consisting of CIN1, LBOOST and the power MOSFET): Only the alternate content
of the input current IIN is considered.
the output current “window”: (path consisting of the power MOSFET, DBOOST and COUT): Output current ripple ∆I
The area of these “windows” has to be kept as small as possible, with the relating elements placed next to each
others. It is highly recommended to use a ground plane as a single layer which covers the complete regulator area
with all components shown in this figure. All connections to ground shall be as short as possible
Radiated electric fields:
Radiated electric fields are caused by voltage oscillations occurring due to stray inductances and stray
capacitances at the connection between power MOSFET, output diode DBOOST and output capacitor COUT. They
are also of course influenced by the commutation of the current from the power MOSFET to the output diode
DBOOST. Their frequencies might be between 10 and 100 MHz. Therefore it is recommended to use a fast Schottky
diode and to keep the connections in this area as low inductive as possible. This can be achieved by using short
and broad connections and to arrange the related parts as close as possible. Following the recommendation of
using a ground layer these low inductive connections will form together with the ground layer small capacitances
which are desirable to damp the slope of these oscillations. The oscillations use connections or wires as antennas,
this effect can also be minimized by the short and broad connections.
Data Sheet
26
Rev. 1.0, 2010-10-25
TLE8386-2EL
Application Information
Conducted disturbances:
Conducted disturbances are voltage spikes or voltage oscillations, occurring permanently or by occasion mostly
on the input or output connections. Comparable to the radiated electric fields they are caused by voltage
oscillations occurring due to stray inductances and stray capacitances at the connection between power MOSFET,
output diode DBOOST and output capacitor COUT.
Their frequencies might be between 10 and 100 MHz. They are super positioned to the input and output voltage
and might thus disturb other components of the application.
The countermeasures against conducted disturbances are similar to the radiated electric fields:
•
•
•
•
it is recommended to use short an thick connections between the single parts of the converter
all parts shall be mounted close together
additional Filter capacitors (ceramic, with low ESR) in parallel to the output and input capacitor and as close
as possible to the switching parts. Input and load current must be forced to pass these devices, do not connect
them via thin lines. Recommended values from 10nF to 220nF
for the input filter a so called “p” – Filter for maximum suppression might be necessary, which requires
additional capacitors on the input
10.2.2
•
•
•
Additional information
Please contact us for information regarding the Pin FMEA.
and for existing application notes with more detailed information about the possibilities of this device
For further information you may contact http://www.infineon.com/
Data Sheet
27
Rev. 1.0, 2010-10-25
TLE8386-2EL
Package Outlines
11
Package Outlines
0.15 M C A-B D 14x
0.64 ±0.25
1
8
1
7
0.2
M
D 8x
Bottom View
3 ±0.2
A
14
6 ±0.2
D
Exposed
Diepad
B
0.1 C A-B 2x
14
7
8
2.65 ±0.2
0.25 ±0.05 2)
0.08 C
8˚ MAX.
C
0.65
0.1 C D
0.19 +0.06
1.7 MAX.
Stand Off
(1.45)
0 ... 0.1
0.35 x 45˚
3.9 ±0.11)
4.9 ±0.11)
Index Marking
1) Does not include plastic or metal protrusion of 0.15 max. per side
2) Does not include dambar protrusion
PG-SSOP-14-1,-2,-3-PO V02
Figure 11
PG-SSOP-14
Green Product (RoHS compliant)
To meet the world-wide customer requirements for environmentally friendly products and to be compliant with
government regulations the device is available as a green product. Green products are RoHS-Compliant (i.e
Pb-free finish on leads and suitable for Pb-free soldering according to IPC/JEDEC J-STD-020).
For further package information, please visit our website:
http://www.infineon.com/packages.
Data Sheet
29
Dimensions in mm
Rev. 1.0, 2010-10-25
TLE8386-2EL
Revision History
12
Revision History
1.0
Revision
Date
Changes
1.0
2010-10-25
Data Sheet
Data Sheet
30
Rev. 1.0, 2010-10-25
Edition 2010-10-25
Published by
Infineon Technologies AG
81726 Munich, Germany
© 2010 Infineon Technologies AG
All Rights Reserved.
Legal Disclaimer
The information given in this document shall in no event be regarded as a guarantee of conditions or
characteristics. With respect to any examples or hints given herein, any typical values stated herein and/or any
information regarding the application of the device, Infineon Technologies hereby disclaims any and all warranties
and liabilities of any kind, including without limitation, warranties of non-infringement of intellectual property rights
of any third party.
Information
For further information on technology, delivery terms and conditions and prices, please contact the nearest
Infineon Technologies Office (www.infineon.com).
Warnings
Due to technical requirements, components may contain dangerous substances. For information on the types in
question, please contact the nearest Infineon Technologies Office.
Infineon Technologies components may be used in life-support devices or systems only with the express written
approval of Infineon Technologies, if a failure of such components can reasonably be expected to cause the failure
of that life-support device or system or to affect the safety or effectiveness of that device or system. Life support
devices or systems are intended to be implanted in the human body or to support and/or maintain and sustain
and/or protect human life. If they fail, it is reasonable to assume that the health of the user or other persons may
be endangered.