TLE6389_07 Datasheet, PDF (27/38 Pages) Infineon Technologies AG – Step-Down DC/DC Controller

TLE 6389
7
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.
7.1
General
The TLE 6389 step-down DC-DC controllers are designed primarily for use in
Automotive applications where high input voltage range requirements have to be met.
Using an external P-MOSFET and current-sense resistor allows design flexibility and the
improved efficiencies associated with high-performance P-channel MOSFETs. The
unique, peak current-limited, PWM/PFM control scheme gives these devices excellent
efficiency over wide load ranges, while drawing around 100µA current from the battery
under no load condition. This wide dynamic range optimizes the TLE 6389 for
automotive applications, where load currents can vary considerably as individual circuit
blocks are turned on and off to conserve energy. Operation to a 100% duty cycle allows
the lowest possible dropout voltage, maintaining operation during cold cranking. High
switching frequencies and a simple circuit topology minimize PC board area and
component costs.
7.2
Typical application circuits
Note: These are very simplified examples of an application circuit. The function must be
verified in the real application
.
V_IN
R_SENSE=
47mΩ
M1
L₁ = 47 µH
V _OUT
I_OUT
C_IN1=
100 µF
C_BDS=
220 nF
C_OUT =
D1
100 µF
R_SI1=
400kΩ
R_SI2=
100kΩ
C_IN2 =
220nF
11
14
12
2
13 ^BDS
VS
7 _SI
CS
GDRV _FB
3
VOUT
TLE6389-2 GV50
9
SO
TLE6389-3 GV50
8
COMP
SI_GND SI_ENABLE
6
1
SYNC GND RO
5
4
10
2.2nF 680Ω
ON OFF
M1: Infineon BSO613SPV
Infineon BSP613P
D1: Motorola MBRD360
L1: EPCOS B82479-A1473-M
Coilcraft DO3340P-473
C_IN1: Electrolythic
C_IN2: Ceramic
C_OUT: Low ESR Tantalum
Figure 2 Application circuit TLE6389-2 GV50 and TLE6389-3 GV50
Datasheet Rev. 2.1
27
2007-08-13