TPS51117 Datasheet, PDF (1/22 Pages) Texas Instruments – SINGLE SYNCHRONOUS STEP-DOWN CONTROLLER

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TPS51117
SLVS631 – DECEMBER 2005
SINGLE SYNCHRONOUS STEP-DOWN CONTROLLER
FEATURES
• High Efficiency, Low Power Consumption,
4.5-µA Typical Shutdown Current
• Fixed Frequency Emulated On-Time Control,
Adjustable from 100 kHz to 550 kHz
• Fast Transient Response
• < 1% Initial Reference Accuracy
• Output Voltage Range: 0.75 V to 5.5 V
• Wide Input Voltage Range: 1.8 V to 28 V
• Selectable Auto-Skip/PWM-Only Operation
• Temperature Compensated (4500 ppm/°C)
Low-Side R_DS(on) Overcurrent Sensing
• Negative Overcurrent Limit
• Integrated Boost Diode
• Integrated OVP/UVP and Thermal Shutdown
• Power-Good Signal
• Internal 1.2-ms Voltage Softstart
• Output Discharge (Softstop)
APPLICATIONS
• Notebook Computers
• I/O Supplies
• System Power Supplies
DESCRIPTION
The TPS51117 is a cost effective, synchronous buck
controller for POL voltage regulation in notebook PC
applications. The controller is dedicated for Adaptive
On-Time D-CAP™ Mode operation that provides
ease of use, low external component count, and
excellent fast transient response at the same time.
Auto-skip mode for high efficiency down to the
milli-ampere load range, or PWM-only mode for low
noise operation is selectable.
The current sensing scheme for positive overcurrent
and negative overcurrent protection is loss-less
low-side R_DS(on) sensing plus temperature
compensation. The device receives 5-V (4.5 V to 5.5
V) supply from another regulator such as the
TPS51120 or TPS51020 in the NBPC system. The
conversion input can be either VBAT or 5-V rail,
ranging from 1.8 V to 28 V, and the output voltage
range is from 0.75 V to 5.5 V.
The TPS51117 is available in the 14-pin TSSOP
package and is specified from –40°C to 85°C.
+5V +
EN_PSV
TPS51117PW
C4
1 _{EN_PSV}
R3
2 _TON
VBST ¹⁴
DRVH ¹³
R5
R6
3 _VOUT
4 _V5FILT
LL ¹²
R4
TRIP ¹¹
C3
5 _VFB
V5DRV ¹⁰
PGOOD
6 _{PGOOD DRVL} 9
7 _GND
PGND 8
GND
VIN
+ _1.8V~28V
C2
Q1
L1
+ _VOUT
R1
C1
Q2
R2
- _PGND
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas
Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
D-CAP is a trademark of Texas Instruments.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2005, Texas Instruments Incorporated