MC33972A Datasheet | Freescale Semiconductor

Freescale Semiconductor Advance Information Document Number: MC33972 Rev. 9.0, 4/2007 Multiple Switch Detection Interface with Suppressed Wake-Up The 33972 Multiple Switch Detection Interface with Suppressed Wake-Up is designed to detect the closing and opening of up to 22 switch contacts. The switch status, either open or closed, is transferred to the microprocessor unit (MCU) through a serial peripheral interface (SPI). The device also Features a 22-to-1 analog multiplexer for reading inputs as analog. The analog input signal is buffered and provided on the AMUX output pin for the MCU to read. The 33972 device has two modes of operation, Normal and Sleep. Normal mode allows programming of the device and supplies switch contacts with pullup or pulldown current as it monitors switch change of state. The Sleep mode provides low quiescent current, which makes the 33972 ideal for automotive and industrial products requiring low sleep state currents. Features - - - - - - - .. - - - Designed to Operate 5.5 V ≤ VPWR ≤ 26 V Switch Input Voltage Range -14 V to VPWR, 40 V Max Interfaces Directly to MPU using 3.3 V / 5.0 V SPI Protocol Selectable Wake-Up on Change of State Selectable Wetting Current (16 m A or 2.0 m A) 8 Programmable Inputs (Switches to Battery or Ground) 14 Switch-to-Ground Inputs Typical Standby Current - VPWR = 100 µA and VDD = 20 µA Active Interrupt (INT) on Change-of-Switch State Pb-Free Packaging Designated by Suffix Code EW 33972 33972A MULTIPLE SWITCH DETECTION INTERFACE DWB SUFFIX EW SUFFIX (Pb-FREE) 98ARH99137A 32-PIN SOICW ORDERING INFORMATION Device MC33972DWB/R2 MC33972EW/R2 MCZ33972AEW/R2 -40°C to 125°C 32 SOICW Temperature Range (TA) Package VDD VBAT VBAT SP0 SP1 VBAT SP7 Power Supply LVI VDD VDD WAKE SI SCLK CS SO INT AMUX MOSI SCLK CS MISO INT AN0 Enable Watchdog Reset MCU VPWR SG0 SG1 SG12 SG13 Figure 1. 33972 Simplified Application Diagram - This document contains certain information on a new product....