LT3791-1_15 Datasheet, PDF (1/26 Pages) Linear Technology – 60V 4-Switch Synchronous Buck-Boost Controller

LT3791-1
60V 4-Switch Synchronous
Buck-Boost Controller
Features
n _{4-Switch Single Inductor Architecture Allows VIN}
Above, Below or Equal to V_OUT
n _{Synchronous Switching: Up to 98.5% Efficiency}
n _{Wide VIN Range: 4.7V to 60V}
n _{2% Output Voltage Accuracy: 1.2V ≤ VOUT < 60V}
n _{6% Output Current Accuracy: 0V ≤ VOUT < 60V}
n _{Input and Output Current Regulation with Current}
Monitor Outputs
n _{No Top FET Refresh in Buck or Boost}
n _{VOUT Disconnected from VIN During Shutdown}
n _{C/10 Charge Termination and Output Shorted Flags}
n _{Capable of 100W or greater per IC}
n _{38-Lead TSSOP with Exposed Pad}
Applications
n _{Automotive, Telecom, Industrial Systems}
n _{High Power Battery-Powered System}
Description
The LT^®3791-1 is a synchronous 4-switch buck-boost volt-
age/current regulator controller. The controller can regulate
output voltage, output current, or input current with input
voltages above, below, or equal to the output voltage. The
constant-frequency, current mode architecture allows its
frequency to be adjusted or synchronized from 200kHz
to 700kHz. No top FET refresh switching cycle is needed
in buck or boost operation. With 60V input, 60V output
capability and seamless transitions between operating
regions, the LT3791-1 is ideal for voltage regulator, bat-
tery/super-capacitor charger applications in automotive,
industrial, telecom, and even battery-powered systems.
The LT3791-1 provides input current monitor, output
current monitor, and various status flags, such as C/10
charge termination and shorted output flag.
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear
Technology Corporation. All other trademarks are the property of their respective owners.
Typical Application
120W (24V 5A) Buck-Boost Voltage Regulator
V_IN
12V TO
58V
0.003Ω
1µF
50Ω
470nF
499k
499k
56.2k
27.4k ^INTVCC
100k
200k
0.1µF
100k
V_IN
INTV_CC
IVINN
IVINP
TEST1
EN/UVLO
OVLO
BST2
BST1
TG1
SWI
BG1
LT3791-1
SNSP
SHORT
C/10
CCM
IVINMON
ISMON
CLKOUT
PWMOUT
V_REF
PWM
CTRL _{SS SYNC VC}
SNSN
PGND
BG2
SW2
TG2
ISP
ISN
RT SGND ^FB
33nF
5.1k 147k
200kHz
10nF
0.1µF
0.1µF
10µH
0.004Ω
4.7µF
4.7µF ⁺ 47µF
100V
80V
+ _220µF
35V
0.015Ω
4.7µF
50V
×2
V_OUT
24V
5A
73.2k
3.83k
37911 TA01a
For more information www.linear.com/LT3791-1
Efficiency vs Load Current
100
95
90
85
80
75
70
V_IN = 12V
65
V_IN = 24V
V_IN = 54V
60
0
1
2
3
4
5
LOAD CURRENT (A)
37911 TA01b
37911fa
1