TPS5103 Datasheet, PDF (1/37 Pages) Texas Instruments – MULTIPLE MODE SYNCHRONOUS DC/DC CONTROLLER

TPS5103
MULTIPLE MODE SYNCHRONOUS DC/DC CONTROLLER
D Step-Down DC-DC Converter
D Three Operation-Mode
– Heavy Load:
– Fixed Frequency PWM
– Hysteretic (User Selctable)
– Light Load:
– Skip Mode
D 4.5 V to 25 V Input Voltage Range
D Adjustable Output Voltage Down to 1.2 V
D 95% Efficiency
D Stand-By Control
D Over Current Protection
D UVLO for Internal 5 V Regulation
D Low Standby Current . . . 0.5 mA Typical
D T_A = –40°C to 85°C
SLVS240 – SEPTEMBER 1999
DB PACKAGE
(TOP VIEW)
SOFTSTART 1
INV 2
FB 3
C_T 4
R_T 5
GND 6
REF 7
COMP 8
PWMSKIP 9
STBY ¹⁰
20 LH
19 OUT_u
18 LL
17 OUT_d
16 OUTGND
15 TRIP
14 VCC_SENSE
13 VCC
12 VREF5
11 _{VREG5V_IN}
description
The TPS5103 is a synchronous buck dc/dc controller, designed for notebook PC system power. The controller
has three user-selectable operation modes available; hysteretic mode, fixed frequency PWM control, or SKIP
control.
In high current applications, where fast transient response is advantageous for reducing bulk capacitance, the
hysteretic mode is selected by connecting the Rt pin to Vref5. Selecting the PWM/SKIP modes for less
demanding transient applications is ideal for conserving notebook battery life under light load conditions. The
device includes high-side and low-side MOSFET drivers capable of driving low Rds (on) N–channel MOSFETs.
The user-selectable overcurrent protection (OCP) threshold is set by an external TRIP pin resister in order to
protect the system. The TPS5103 is configured so that a current sense resistor is not required, improving the
operating efficiency.
C4
5V
C1
R2
C2
R1
U1
TPS5103
1
20
SOFTSTART
LH
2 _INV
3
19
OUTU ₁₈
FB
4
LL ₁₇
CT
5
OUTD ₁₆
RT
6
OUTGND ₁₅
GND
TRIP
7 _REF
8
14
VCCSENSE ₁₃
COMP
VCC
9 _PWM/SKIP
12
VREF5
10 _STBY
11
VREG5V_IN
D1
C3
R3
R4
Q1
OUTPUT
L1
C5 ⁺
Q2
Figure 1. Typical Design
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TI is a trademark of Texas Instruments Incorporated.
PRODUCT PREVIEW information concerns products in the formative or
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specifications are design goals. Texas Instruments reserves the right to
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Copyright © 1999, Texas Instruments Incorporated
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