TPS5110_16 Datasheet, PDF (1/43 Pages) Texas Instruments – SYNCHRONOUS-BUCK PWM CONTROLLER WITH NMOS LDO CONTROLLER

TPS5110
SLVS025B − APRIL 2002 − REVISED JULY 2004
SYNCHRONOUSĆBUCK PWM CONTROLLER
WITH NMOS LDO CONTROLLER
FEATURES
D Switching Mode Step-Down dc-to-dc
Controller With Fast LDO Controller
D Input Voltage Range
Switcher: 4.5 V to 28 V
LDO: 1.1 V to 3.6 V
D Output Voltage Range
Switcher: 0.9 V to 3.5 V
LDO: 0.9 V to 2.5 V
D Synchronous for High Efficiency
D Precision V_REF (±1 %)
D PWM Mode Control: Max. 500-kHz Operation
D High-Speed Error Amplifier
D Overcurrent Protection With Temperature
Compensation Circuit
D Overvoltage and Undervoltage Protection
D Programmable Short-Circuit Protection
APPLICATIONS
D Notebook PCs, PDAs
D Consumer Game Systems
D DSP Application
DESCRIPTION
The TPS5110 provides one PWM-mode synchronous
buck regulator controller (SBRC) and one low drop-out
(LDO) regulator controller. The TPS5110 supports a
low-voltage/high-current power supply for I/O and other
peripherals in modern digital systems. The SBRC of the
TPS5110 automatically adjusts from PWM mode to
SKIP mode to maintain high efficiency under all load
conditions. The LDO controller drives an external
N-channel power MOSFET that realizes fast response
and ultra-low dropout voltage. A unique overshoot
protection circuit prevents a voltage hump at fast load
decreasing transients. The current protection circuit for
SBRC detects the drain-to-source voltage drop across
the low-side and high-side power MOSFET while it is
conducting. Also, the current protection circuit has a
temperature coefficient to compensate for the R_DS(on)
variation of the MOSFET. This resistor-less current
protection simplifies the system design and reduces the
external parts count. The LDO controller includes
current-limit protection. Other features, such as
undervoltage lockout, power good, overvoltage,
undervoltage, and programmable short-circuit
protection promote system reliability.
SIMPLIFIED APPLICATION
TPS5110PW
1 INV
LH 24
OUT_u 23
LL 22
6 GND
OUT_d 21
REG5V_IN 17
LDO_IN 16
LDO_CUR 15
12 INV_LDO
LDO_GATE 14
LDO_OUT 13
UDG-02052
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
VIN
VO1
5V
INPUT
VO2
www.ti.com
LDO Load Transient Response
COUT = 47 µF
VOUT = 1.5 V
(50 mV/ div)
IOUT = 0 A to 3 A
(1 A/ div)
t− time 100 µs/div
Copyright  2002, Texas Instruments Incorporated
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