IC manufacturers Texas Instruments

IC manufacturers (103)

Texas Instruments SN6505 | Demoboard PMP23126

Low-noise, 1-A, 420-kHz transformer driver with soft start for isolated power supplies

Overview

TopologyPush-Pull Converter symmetrical isolated
IC revisionB

Description

The SN6505x is a low-noise, low-EMI push-pull transformer driver, specifically designed for small form factor, isolated power supplies. It drives low-profile, center-tapped transformers from a 2.25 V to 5 V DC power supply. Ultra-low noise and EMI are achieved by slew rate control of the output switch voltage and through Spread Spectrum Clocking (SSC). The SN6505x consists of an oscillator followed by a gate drive circuit that provides the complementary output signals to drive ground-referenced N-channel power switches. The device includes two 1-A Power-MOSFET switches to ensure start-up under heavy loads. The switching clock can also be provided externally for accurate placement of switcher harmonics, or when operating with multiple transformer drivers. The internal protection features include a 1.7 A current limiting, under-voltage lockout, thermal shutdown, and break-before-make circuitry. SN6505x include s a soft-start feature that prevents high inrush current during power up with large load capacitors. SN6505A has a 160 kHz internal oscillator for applications that need to minimize emissions whereas SN6505B has a 420 kHz internal oscillators for applications that require higher efficiency and smaller transformer size. The SN6505x is available in a small 6-pin SOT23/DBV package. The device operation is characterized for a temperature range from –55°C to 125°C.

Features

  • 270-W/in3 power density in an x-y dimension of less than 68 mm x 102 mm and max height of 32 mm

  • Peak efficiency of 97.74%
  • Active clamp for minimizing voltage stress on SR MOSFETs enabling use of better FoM devices
  • GaN optimized with driver integration

Typical applications

  • Merchant telecom rectifiers
  • DC/DC converter, Merchant network and server PSU, Switch-mode power converters
  • On-board (OBC) and wireless charge

Products

Order Code
Data­sheet
Downloads
Status
Product series
VIN
VOut1(V (DC))
IOut1(A)
Type of Insulation
fswitch(kHz)
∫Udt(Vµs)
NPRI : NSEC
L(µH)
VT(V (AC))
L(mm)
W(mm)
H(mm)
Mount
Samples
WE-PPTI Push-Pull Transformers, 5 V (DC), 5 V (DC)
Status Activei| Production is active. Expected lifetime: >10 years.
Input Voltage 5 V (DC)
Output Voltage 15 V (DC)
Output Current 10.6 A
Type of InsulationFunctional 
Switching Frequency 300 - 620
Voltage-µSecond11 Vµs
Turns Ratio1:1.3 
Inductance475 µH
Insulation Test Voltage2500 V (AC)
Length6.73 mm
Width10.2 mm
Height4.19 mm
MountSMT