LTC2645 Quad 12-/10-/8-Bit PWM to V OUT DACs with 10ppm/C Reference FEATURES DESCRIPTION n No Latency PWM-to-Voltage Conversion The LTC 2645 is a family of quad 12-, 10-, and 8-bit n Voltage Output Updates and Settles within 8s PWM-to-voltage output DACs with an integrated high n 100kHz to 30Hz PWM Input Frequency accuracy, low drift, 10ppm/C reference in a 16-lead n 2.5LSB Max INL 1LSB Max DNL (LTC2645-12) MSOP package. It has rail-to-rail output buffers and is n Guaranteed Monotonic guaranteed monotonic. n Pin-Selectable Internal or External Reference The LTC2645 measures the period and pulse width of the n 2.7V to 5.5V Supply Range PWM input signals and updates the voltage output DACs n 1.71V to 5.5V Input Voltage Range after each corresponding PWM input rising edge. The DAC n Low Power: 4mA at 3V, <1A Power-Down outputs update and settle to 12-bit accuracy within 8s n Guaranteed Operation from 40C to 125C typically and are capable of sourcing and sinking up to n 16-Lead MSOP Package 5mA (3V) or 10mA (5V), eliminating voltage ripple and replacing slow analog filters and buffer amplifiers. APPLICATIONS The LTC2645 has a full-scale output of 2.5V using the 10ppm/C internal reference. It can operate with an exter- n Digital Calibration nal reference, which sets the full-scale output equal to the n Trimming and Adjustment external reference voltage. Each DAC enters a pin-select- n Level Setting able idle state when the PWM input is held unchanged for n Process Control and Industrial Automation more than 60ms. The part operates from a single 2.7V n Instrumentation to 5.5V supply and supports PWM input voltages from n Automotive 1.71V to 5.5V. All registered trademarks and trademarks are the property of their respective owners. Protected by U.S. patents, including 5396245, 5859606, 6891433, 6937178, 7414561. TYPICAL APPLICATION 4-Channel PWM to Voltage Output DAC PWM Input to DAC Output PWM INPUTS IN V A OUTA BUFFERED IN IN V B OUTB A VOLTAGE 2V/DIV IN V C OUTC OUTPUTS IN V D OUTD 1.7V TO 5.5V LTC2645 INPUT: 1V TO 5.5V IOV REF CC OUTPUT: 1.25V 2.7V TO 5.5V PD 0.1F V CC GND IDLSEL 0.1F 0.1F REFSEL V OUTA 500mV/DIV GND TA01b 2645 TA01a 20s/DIV Rev. B 1 Document Feedback For more information www.analog.comLTC2645 ABSOLUTE MAXIMUM RATINGS PIN CONFIGURATION (Notes 1, 2) Supply Voltages (V , IOV ) ...................... 0.3V to 6V CC CC IN , IN , IN , IN ......................................... 0.3V to 6V A B C D TOP VIEW V 1 16 GND IDLSEL, PD, REFSEL .................................... 0.3V to 6V CC V 2 15 V OUTA OUTD V , V , V , V 3 14 V OUTA OUTB OUTC OUTB OUTC IDLSEL 4 13 REFSEL V ...............................0.3V to Min (V + 0.3V, 6V) IN 5 12 REF OUTD CC B IN 6 11 IN A C REF ..................................0.3V to Min (V + 0.3V, 6V) CC IOV 7 10 IN CC D GND 8 9 PD Operating Temperature Range MS PACKAGE LTC2645C ................................................ 0C to 70C 16-LEAD PLASTIC MSOP LTC2645I .............................................40C to 85C (4mm 4.9mm) T = 150C, = 120C/W LTC2645H .......................................... 40C to 125C JMAX JA Maximum Junction Temperature .......................... 150C Storage Temperature Range .................. 65C to 150C Lead Temperature (Soldering, 10 sec) ...................300C Rev. B 2 For more information www.analog.com