LTC3622-2_15 Datasheet, PDF (1/24 Pages) Linear Technology – 17V, Dual 1A Synchronous Step-Down Regulator with Ultralow Quiescent Current

LTC3622/
LTC3622-2/LTC3622-23/5
Features
17V, Dual 1A
Synchronous Step-Down Regulator
with Ultralow Quiescent Current
Description
n _{Dual Step-Down Outputs: 1A Per Channel}
n _{Wide VIN Range: 2.7V to 17V}
n _{Wide VOUT Range: 0.6V to VIN}
n _{Up to 95% Efficiency}
n _{No-Load IQ = 5µA with Both Channels Enabled;}
I_Q < 4µA with Only One Channel Enabled
n _{High Efficiency, Low Dropout Operation}
(100% Duty Cycle)
n _{Constant Frequency (1MHz/2.25MHz) with External}
Frequency Synchronization
n _{±1% Output Voltage Accuracy}
n _{Current Mode Operation for Excellent Line and Load}
Transient Response
n _{Phase Shift Programmable with External Clock}
n _{Selectable Current Limit}
n _{Internal Compensation and Soft-Start}
n _{Compact 14-Pin DFN (3mm × 4mm) and 16-Lead}
MSOP Packages
Applications
n _{Battery Powered Systems}
n _{Point-of-Load Supplies}
n _{Portable – Handheld Scanners}
The LTC^®3622 is a dual 1A output, high efficiency synchro-
nous monolithic step-down regulator capable of operating
from input supplies up to 17V. The switching frequency is
fixed to 1MHz or 2.25MHz with a ±50% synchronization
range to an external clock. The regulator features ultralow
quiescent current and high efficiency over a wide output
voltage range.
The step-down regulators operate from an input voltage
range of 2.7V to 17V and provide an adjustable output
from 0.6V to V_IN while delivering up to 1A of output cur-
rent. A user-selectable mode input is provided to allow
the user to trade off ripple noise for light load efficiency.
Burst Mode^® operation provides the highest efficiency at
light loads, while pulse-skipping mode provides the lowest
ripple noise. The switching regulators can be synchronized
to an external clock. Furthermore, fixed V_OUT options are
available to eliminate the external feedback resistors.
List of LTC3622 Options
PART NAME
FREQUENCY
LTC3622
1.00MHz
LTC3622-2
2.25MHz
LTC3622-23/5 2.25MHZ
V_OUT
Adjustable
Adjustable
5V/3.3V
L, LT, LTC, LTM, Burst Mode, Linear Technology and the Linear logo are registered trademarks
and Hot Swap is a trademark of Linear Technology Corporation. All other trademarks are the
property of their respective owners. Protected by U.S. Patents, including 5481178, 6580258,
6498466, 6611131, 5705919.
Typical Application
2.5V/5V V_OUT Application, f_SW = 1MHz
V_OUT1
2.5V
1A
V_IN
5.5V TO 17V
C_IN
10µF
C_OUT1
22µF
22pF
4.7µH
619k
196k
V_IN1
INTV_CC
V_{IN2 MODE/SYNC}
RUN1
RUN2
PHASE
I_LIM
LTC3622
SW1
SW2
FB1
FB2
GND
C1
1µF
6.8µH
619k
84.5k
22pF
V_OUT2
5V
1A
C_OUT2
22µF
3622 TA01
For more information www.linear.com/LTC3622
Efficiency vs Load Current
100
0.6
90
80
70
60
50
40
30
V_OUT1 = 2.5V
V_OUT2 = 5V
20 _{VIN = 12V}
10
f_SW = 1MHz
BURST MODE OPERATION
0
0.0001 0.001
0.01
0.1
LOAD CURRENT (A)
0.5
0.4
0.3
0.2
0.1
0
1
3622 TA01b
3622fa
1