TPS51427

Features:

` Fixed-Frequency Emulated On-Time Control; Frequency Selectable from Three Options
` D-CAP™ Mode Enables Fast Transient Response Less than 100 ns
` Advanced Ramp Compensation Allows Low Output Ripple with Minimal Jitter
` Selectable PWM-Only/OOA™/Auto-Skip Modes
` Wide Input Voltage Range: 5.5 V to 28 V
` Dual Fixed or Adjustable SMPS:
0.7 V to 5.9 V (Channel1)
0.5 V to 2.5 V (Channel2)
` Fixed 3.3-V/5-V, or Adjustable Output 0.7-V to 4.5-V LDO; Capable of Sourcing 100 mA
` Fixed 3.3-VREF Output Capable of Sourcing 10 mA
` Temperature Compensated Low-Side R<sub>DS(on)</sub> Current Sensing
` Adaptive Gate Drivers with Integrated Boost Switch
` Bootstrap Charge Auto Refresh
` Integrated Soft Start, Tracking Soft Stop
` Independent PGOOD and EN for Each Channel




Application

· Notebook I/O and System Bus Rails
· Graphics Application
· PDAs and Mobile Communication Devices


Specifications

PARAMETER			VALUE	UNIT
5V voltage range	V5DRV, V5FILT		0.3 to 7	V
Input voltage range(2)	VIN, ENLDO		0.3 to 30
	VBST1, VBST2		0.3 to 37
	VBST1, VBST2 (w.r.t. LLx)		0.3 to 7
	EN1, EN2, VOUT1, VOUT2, VFB1, REFIN2, TRIP1, TRIP2, SKIPSEL, TONSEL, VSW, LDOREFIN		0.3 to 7
	TRIP1, TRIP2		0.3 to (V5FILT + 0.3)
Output voltage range(2)	DRVH1, DRVH2		2 to 37	V
	DRVH1, DRVH2 (w.r.t. LLx)		0.3 to 7
	LL1, LL2		2 to 30
	DRVL1, DRVL2, VREF2, PGOOD1, PGOOD2, LDO, VREF3		0.3 to 7
	PGND		0.3 to 0.3
Tstg Storage temperature range			55 to +150
TJ Junction temperature range			+150

(1) Stresses beyond those listed under absolute maximum ratings may cause permanent damage to the
     device.  These are stress ratings only, and functional operation of the device at these or any other
     conditions beyond those indicated under recommended operating conditions is not implied. Exposure to
     absolute-maximum-rated conditions for extended periods may affect device reliability.
(2) All voltage values are with respect to the network ground terminal unless otherwise noted.




Description

The TPS51427 is a dual synchronous step-down controller designed for notebook and mobile communications applications. This device is part of a low-cost suite of notebook power bus regulators that enables system designs with low external component counts. The TPS51427 includes two. pulse-width-modulation (PWM) controllers, SMPS1
and SMPS2. The output of SMPS1 can be adjusted from 0.7 V to 5.9 V, while the output of SMPS2 can  be adjusted from 0.5 V to 2.5 V. This TPS51427 also features a low-dropout (LDO) regulator that provides a 5-V/3.3-V output, or adjustable from 0.7-V to 4.5-V output via LDOREFIN. The fixed-frequency emulated  adaptive on-time control supports seamless operation between PWM mode under heavy load conditionsand reduced frequency operation at light loads for high-efficiency down to the milliampere range. An integrated boost switch enhances the high-side   MOSFET to further improve efficiency. The main control loop of TPS51427  is the D-CAP™ mode that is optimized output capacitors such as POSCAP or SP-CAP. Advanced ramp compensation minimizes jitter without degrading line and load regulation. RDS(on) current sensing methods offers maximum cost saving.

The TPS51427 supports supply input voltages that range from 5.5 V to 28 V. It is available in the 32-pin, 5-mm * 5-mm QFN package (Green, RoHs-  compliant, and Pb-free). The device is specified from 40 to +85