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TPS65321A-Q1
SLVSE55 –NOVEMBER 2017
TPS65321A-Q1 36-V Step-Down Converter With Eco-mode™ and LDO Regulator
1 Features
2 Applications
1
•
Qualified for Automotive Applications
•
•
•
Automotive Infotainment and Cluster
Advanced Driver Assistance System (ADAS)
Automotive Telematics, eCall
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AEC-Q100 Qualified with the Following Results:
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Device Temperature Grade 1: –40°C to
+125°C Ambient Operating Temperature
3 Description
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Device HBM ESD Classification Level 2
Device CDM ESD Classification Level C4B
The TPS65321A-Q1 device is a combination of a
high-VIN DC-DC step-down converter, referred to as
the buck regulator, with an adjustable switch-mode
frequency from 100-kHz to 2.5-MHz, and a high-VIN
280-mA low-dropout (LDO) regulator. The input range
is 3.6 V to 36 V for the buck regulator, and 3 V to
36 V for the LDO regulator. The buck regulator has
an integrated high-side MOSFET with an active-low,
open-drain power-good output-pin (nRST). The LDO
regulator features a low-input supply current of 45-μA
typical in no-load, also has an integrated MOSFET.
Low-voltage tracking feature enables TPS65321A-Q1
to track the input supply during cold-crank conditions.
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One High-VIN Step-Down DC-DC Converter
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Input Range of 3.6 V to 36 V
250-mΩ High-Side MOSFET
Maximum Load Current 3.2 A, Output
Adjustable 1.1 V to 20 V
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Adjustable Switching Frequency 100 kHz to
2.5 MHz
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Synchronizes to External Clock
High Efficiency at Light Loads With Pulse-
Skipping Eco-mode™ Control Scheme
The buck regulator provides a flexible design to fit
system needs. The external loop compensation circuit
allows for optimization of the converter response for
the appropriate operating conditions. A low-ripple
pulse-skip mode reduces the no-load input-supply
current to maximum 140 μA.
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Maximum 140-µA Operating Quiescent
Current
Reset Output-Pin (Active Low, Open-Drain)
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One High-VIN Low-Dropout (LDO) Voltage
Regulator
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Input Range of 3 V to 36 V
The device has built-in protection features such as
soft start, current-limit, thermal sensing and shutdown
due to excessive power dissipation. Furthermore, the
device has an internal undervoltage-lockout (UVLO)
function that turns off the device when the supply
voltage is too low.
280-mA Current Capability With Typical 35-µA
Quiescent Current in No-Load Condition
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Low-Dropout Voltage of 300 mV at
IO = 200 mA (Typical)
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•
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Overcurrent Protection for Both Regulators
Overtemperature Protection
Device Information(1)
PART NUMBER
PACKAGE
BODY SIZE (NOM)
14-Pin HTSSOP Package With PowerPAD™
Integrated Circuit Package
TPS65321A-Q1
HTSSOP (14)
5.00 mm × 4.40 mm
(1) For all available packages, see the orderable addendum at
the end of the data sheet.
Typical Application Schematic
Buck Efficiency Versus Output Current
VI = 3.6 V to 36 V
Supply
1.1 V to 20 V,
3.2 A
BOOT
SW
VIN
100
90
80
70
60
50
40
30
20
EN1
Buck
Regulator
Control
FB1
RT/CLK
SS
COMP
RST
1.1 V to 5.5 V,
280 mA
VI = 3 V to 36 V
Supply
LDO_OUT
VIN_LDO
fs = 300 kHz
10
fs = 2 MHz
0
GND
EN2
LDO
Regulator
Control
PowerPAD
0
1
2
3
4
FB2
Load Current (A)
D001
TPS65321-Q1
Copyright © 2017, Texas Instruments Incorporated
1
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.