Datasheet LTC3622, LTC3622-2, LTC3622-23/5 (Analog Devices)

LTC3622/ LTC3622-2/LTC3622-23/5 17V, Dual 1A Synchronous Step-Down Regulator with Ultralow Quiescent Current
FEATURES DESCRIPTION
n
Dual Step-Down Outputs: 1A Per Channel
The LTC®3622 is a dual 1A output, high efficiency synchro- n
Wide VIN Range: 2.7V to 17V
nous monolithic step-down regulator capable of operating n
Wide VOUT Range: 0.6V to VIN
from input supplies up to 17V. The switching frequency is n
Up to 95% Efficiency
fixed to 1MHz or 2.25MHz with a ±50% synchronization n
No-Load IQ = 5µA with Both Channels Enabled;
range to an external clock. The regulator features ultralow
IQ < 4µA with Only One Channel Enabled
quiescent current and high efficiency over a wide output n
High Efficiency, Low Dropout Operation
voltage range.
(100% Duty Cycle)
The step-down regulators operate from an input voltage n
Constant Frequency (1MHz/2.25MHz) with External
range of 2.7V to 17V and provide an adjustable output
Frequency Synchronization
from 0.6V to VIN while delivering up to 1A of output cur- n ±1% Output Voltage Accuracy rent. A user-selectable mode input is provided to allow n Current Mode Operation for Excellent Line and Load the user to trade off ripple noise for light load efficiency. Transient Response Burst Mode® operation provides the highest efficiency at n Phase Shift Programmable with External Clock light loads, while pulse-skipping mode provides the lowest n Selectable Current Limit ripple noise. The switching regulators can be synchronized n Internal Compensation and Soft-Start to an external clock. Furthermore, fixed VOUT options are n Compact 14-Pin DFN (3mm × 4mm) and 16-Lead available to eliminate the external feedback resistors. MSOP Packages
List of LTC3622 Options APPLICATIONS PART NAME FREQUENCY VOUT
LTC3622 1.00MHz Adjustable n Battery Powered Systems LTC3622-2 2.25MHz Adjustable n Point-of-Load Supplies LTC3622-23/5 2.25MHZ 5V/3.3V n Portable – Handheld Scanners All registered trademarks and trademarks are the property of their respective owners. Protected by U.S. Patents, including 5481178, 6580258, 6498466, 6611131, 5705919.
TYPICAL APPLICATION 2.5V/5V VOUT Application, fSW = 1MHz Efficiency vs Load Current
100 0.6 V 90 IN V 5.5V TO 17V IN1 INTVCC 0.5 80 VIN2 MODE/SYNC CIN C1 RUN1 70 POWER LOSS (W) 10µF 1µF 0.4 RUN2 PHASE 60 ILIM 50 0.3 LTC3622 40 EFFICIENCY (%) VOUT1 4.7µH 6.8µH VOUT2 V 0.2 30 OUT1 = 2.5V 2.5V SW1 SW2 5V VOUT2 = 5V 1A 1A 20 V 22pF 619k 619k IN = 12V 22pF 0.1 COUT1 C 10 fSW = 1MHz FB1 FB2 OUT2 Burst Mode OPERATION 22µF GND 22µF 0 0 196k 84.5k 0.0001 0.001 0.01 0.1 1 LOAD CURRENT (A) 3622 TA01b 3622 TA01 Rev D Document Feedback For more information www.analog.com 1 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Applications Package Description Revision History Typical Application Related Parts