LM3544MX-H National Semiconductor, LM3544MX-H Datasheet
![](/photos/31/32/313246/16pin_soic_n_sml.jpg)
LM3544MX-H
Specifications of LM3544MX-H
Related parts for LM3544MX-H
LM3544MX-H Summary of contents
Page 1
... Functional Diagram © 2005 National Semiconductor Corporation Features n Compatible with USB1.1 and USB 2.0 n 90mΩ (typ.) High-Side MOSFET Switch n 500mA Continuous Current per Port ...
Page 2
... Ordering Information Part Number LM3544M-H Active High Enable LM3544M-L Active Low Enable LM3544MX-H Active High Enable, 2500 units per reel LM3544MX-L Active Low Enable, 2500 units per reel Typical Application Circuit FIGURE 1. The LM3544 used in a Self-Powered or Root USB Hub www.national.com ...
Page 3
... Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Voltage at IN and OUT pins X X Voltage at EN (EN ) and FLAG pins Power Dissipation (Note 2) Maximum Junction Temperature Storage Temperature Range DC Electrical Characteristics ...
Page 4
AC Electrical Characteristics Limits are for T = 25˚C and V = 5.0V Symbol Parameter t OUT Rise Time (Note OUT Fall Time (Note Turn-on Delay (Note ...
Page 5
Typical Performance Characteristics fied Input Voltage ON Quiescent Current, Output(s) Enabled vs Junction Temperature Quiescent Current, Output(s) Enabled vs Input Voltage 500mA OUT_X R ON 10120805 Quiescent Current, Output(s) Disabled vs ...
Page 6
Typical Performance Characteristics specified. (Continued) Short-Circuit Output Current vs Junction Temperature (Note 10) Under-Voltage Lockout (UVLO) Threshold vs Junction Temperature Turn-Off Delay vs Input Voltage ( µ OUT www.national.com OUT_X 10120813 ...
Page 7
Typical Performance Characteristics specified. (Continued) Turn-On/Turn-Off Response with 47Ω/33µF Load Enable Into a Short (Note 10) Over-Current Response with Ramped Load on OUT1 and Fixed Load on OUT2 (Note 10) Note 10: Output is shorted to Ground through a 100 ...
Page 8
Functional Description POWER SWITCHES The power switches that comprise the four ports of the LM3544 are N-Channel MOSFETs. They have a typical on- state drain-to-source resistance of 90 mΩ when the input voltage When enabled, each switch ...
Page 9
Functional Description FIGURE 3. Thermal Shutdown Characteristics when only the First-Stage Thermal-Shutdown Mode is Needed FIGURE 4. Thermal Shutdown Characteristics when Both First-Stage and Second-Stage Thermal-Shutdown Modes are Needed In Figure 3, port 1 is enabled into a short. When ...
Page 10
Application Information tantalum capacitor is recommended. The input supply should be further bypassed with a 0.01 µF - 0.1 µF ceramic capacitor, placed close to the device. The ceramic capacitor reduces ringing on the supply that can occur when a ...
Page 11
Typical Applications ROOT AND SELF-POWERED USB HUBS The LM3544 has been designed primarily for use in root and self-powered USB hubs. In this application, the switches of the LM3544 are used to connect the power source of the hub to ...
Page 12
Typical Applications the LM3544 can be configured to switch the power connec- tion of a device between two separate sources is shown in Figure 8, below. In the example, the logic signals EN and SRC control the power supply connections. ...
Page 13
... Order Number LM3544M-H, LM3544M-L, LM3544MX-H or LM3544MX-L, National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications. ...