Richtek

RT2857B
Demoboard DS2857B-03

6A, 18V, Synchronous Step-Down Converter

Topology: Buck
Input Voltage (min.): 4.50 V
Input Voltage (max.): 18.00 V
Switching Frequency (min.): 200.00 kHz
Switching Frequency (max.): 1600.00 kHz
Output 1: 18.00 V / 6.000 A

Original publication on 2016-01-06, revision DS2857B-03

Description

http://www.richtek.com/assets/product_file/RT2857B/DS2857B-03.pdf6A, 18V, Synchronous Step-Down ConverterThe RT2857B is a high efficiency, monolithic synchronousstep-down DC/DC converter that can deliver up to 6A outputcurrent from a 4.5V to 18V input supply. The RT2857Bcurrent-mode architecture with external compensationallows the transient response to be optimized over a widerange of loads and output capacitors. Cycle-by-cyclecurrent limit provides protection against shorted outputsand soft-start eliminates input current surge during startup.Fault condition protections include output over-currentprotection, output over-voltage protection, and overtemperatureprotection. The low current shutdown modeprovides output disconnection, enabling easy powermanagement in battery-powered systems.

Characteristics

  •  Low RDS(ON) Power MOSFET Switches 26mΩ/19mΩ Input Voltage Range : 4.5V to 18V Adjustable Switching Frequency : 200kHz to 1.6MHz Current-Mode Control Synchronous to External Clock : 200kHz to 1.6MHz Accurate Voltage Reference 0.6V ± 1%, Over −40°Cto 85°C Monotonic Start-Up into Pre-biased Outputs Adjustable Soft-Start Power Good Indicator Over-Current Protection Over-Temperature and Over-Voltage Protection Input Under-Voltage Lockout RoHS Compliant and Halogen Free

Products

  Order Code SPEC Product series L
(µH)
IR
(A)
LR
(µH)
ISAT
(A)
RDC
(mΩ)
fres
(MHz)
Material Version Samples
7443552200 PDF WE-HCI SMT Flat Wire High Current Inductor 2 11 1.48 13 7.3 53 WE-PERM SMT
7443552560 PDF WE-HCI SMT Flat Wire High Current Inductor 5.6 6.7 4.15 7.5 20.6 30 WE-PERM SMT
7443552430 PDF WE-HCI SMT Flat Wire High Current Inductor 4.3 8 3 8 14.1 33 WE-PERM SMT
7443552280 PDF WE-HCI SMT Flat Wire High Current Inductor 2.8 9.5 2.1 11 10.6 46 WE-PERM SMT
7443552150 PDF WE-HCI SMT Flat Wire High Current Inductor 1.5 14 1.1 17 5.3 63 WE-PERM SMT
744325420 PDF WE-HCI SMT Flat Wire High Current Inductor 4.2 11 3.3 14 7.1 33 Superflux SMT
744325550 PDF WE-HCI SMT Flat Wire High Current Inductor 5.5 10 4.3 12 10.3 30 Superflux SMT
744325330 PDF WE-HCI SMT Flat Wire High Current Inductor 3.3 12 2.4 15 5.9 54 Superflux SMT
744325240 PDF WE-HCI SMT Flat Wire High Current Inductor 2.4 14 1.8 17 4.75 67 Superflux SMT
744325180 PDF WE-HCI SMT Flat Wire High Current Inductor 1.8 16 1.4 18 3.5 70 Superflux SMT
744323220 PDF WE-HCI SMT Flat Wire High Current Inductor 2.2 9 1.9 15 11.38 36 Superflux SMT