LMH2190 Datasheet | National Semiconductor

Description The LMH2190 is a quad channel configurable clock distribution device which supplies the system clock to peripherals in mobile handsets or other applications. It provides a solution to clocking issues such as drive capability for fanout or longer traces, protection of the master clock from varying loads and frequency pulling effects, isolation buffering from noisy modules, and crosstalk isolation. It has very low phase noise which enables it to drive sensitive modules such as Wireless LAN and Bluetooth. The LMH2190 can be clocked up to 26 MHz, and has an independent clock request pin for each clock output which allows the peripheral to control the clock. It features an integrated LDO which provides an ultra low noise voltage supply with 10 m A external load current which can be used to supply the TCXO or other clock source. The I2C serial interface can be used to override the default configuration of the device to optimize the LMH2190 for the application. Some of these programmable features include setting the polarity of both the clock and the clock request inputs. In addition, the clock outputs have programmable output drive current to optimize for the connected load. EMI switching noise can be controlled by configuring output drive and skew settings. The LMH2190 quad clock distributor is offered in a tiny 1.5mm x 1.5mm 16 bump micro SMD package. Its’ small size and low supply current make it ideal for portable applications. Features - - - - - - - - - 1 Input Clock, 4 Output Clocks Independent clock request Support both square or sine wave input Skewed clock outputs High isolation of supply noise to clock input High output to output Isolation Output Drive up to 50 p F EMI controlled output edges and EMI filtering Integrated Low-Dropout Regulator - Low Output Noise Voltage - 10 m A load current - I2C Configurable up to 400 k Hz (Fast Mode) - Ultra low standby current - VBAT range = 2.5V to 5.5V Applications - Mobile handsets - PDAs - Portable...