LTC2644 Dual 12-/10-/8-Bit PWM to V DACs with OUT 10ppm/C Reference FEATURES DESCRIPTION n No Latency PWM-to-Voltage Conversion The LTC 2644 is a family of dual 12-, 10-, and 8-bit PWM- n Voltage Output Updates and Settles within 8s to-voltage output DACs with an integrated high accuracy, n 100kHz to 30Hz PWM Input Frequency low drift, 10ppm/C reference in a 12-lead MSOP package. It n 2.5LSB Max INL 1LSB Max DNL (LTC2644-12) has rail-to-rail output buffers and is guaranteed monotonic. n Guaranteed Monotonic The LTC2644 measures the period and pulse width of the n Pin-Selectable Internal or External Reference PWM input signals and updates the voltage output DACs n 2.7V to 5.5V Supply Range after each corresponding PWM input rising edge. The n 1.71V to 5.5V Input Voltage Range DAC outputs update and settle to 12-bit accuracy within n Low Power: 2.7mA at 3V, <1A Power-Down 8s typically and are capable of sourcing and sinking up n Guaranteed Operation from 40C to 125C to 5mA (3V) or 10mA (5V), eliminating voltage ripple and n 12-Lead MSOP Package replacing slow analog filters and buffer amplifiers. The LTC2644 has a full-scale output of 2.5V using the APPLICATIONS 10ppm/C internal reference. It can operate with an external n Digital Calibration reference, which sets the full-scale output equal to the ex- n Trimming and Adjustment ternal reference voltage. Each DAC enters a pin-selectable n Level Setting 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. L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and ThinSOT is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents, including 5396245, 5859606, 6891433, 6937178, 7414561. TYPICAL APPLICATION 2-Channel PWM to Voltage Output DAC PWM Input to DAC Output PWM INPUTS IN A BUFFERED IN V A OUTA 2V/DIV VOLTAGE IN V B OUTB OUTPUTS LTC2644 INPUT: 1V TO 5.5V 1.7V TO 5.5V IOV REF CC OUTPUT: 1.25V PD 0.1F V 2.7V TO 5.5V CC V OUTA 500mV/DIV GND IDLSEL 0.1F 0.1F REFSEL GND 2644 TA01a 2644TA01b 20s/DIV 2644f 1 For more information www.linear.com/LTC2644LTC2644 ABSOLUTE MAXIMUM RATINGS PIN CONFIGURATION (Notes 1, 2) TOP VIEW Supply Voltages (V , IOV ) ...................... 0.3V to 6V CC CC IN , IN ........................................................ 0.3V to 6V V 1 12 GND CC A B 2 V 11 REFSEL OUTA IDLSEL, PD, REFSEL .................................... 0.3V to 6V 3 V 10 REF OUTB IDLSEL 4 9 IN V , V ...................0.3V to Min (V + 0.3V, 6V) A OUTA OUTB CC IOV 5 8 IN CC B REF ..................................0.3V to Min (V + 0.3V, 6V) CC GND 6 7 PD Operating Temperature Range MS PACKAGE 12-LEAD PLASTIC MSOP LTC2644C ................................................ 0C to 70C (4mm 4.9mm) LTC2644I .............................................40C to 85C T = 150C, = 135C/W JMAX JA LTC2644H .......................................... 40C to 125C Maximum Junction Temperature .......................... 150C Storage Temperature Range .................. 65C to 150C Lead Temperature (Soldering, 10 sec) ...................300C 2644f 2 For more information www.linear.com/LTC2644