LTC6943 Micropower, Dual Precision Instrumentation Switched Capacitor Building Block FEATURES DESCRIPTIO Low Power, I = 60A(Max) The LTC 6943 is a monolithic, charge-balanced, dual S Robust, Latch Up Proof switched capacitor instrumentation building block. A pair Instrumentation Front End with 120dB CMRR of switches alternately connects an external capacitor to Precise, Charge-Balanced Switching an input voltage and then connects the charged capacitor Operates from 5V to 18V across an output port. The internal switches have a Internal or External Clock break-before-make action. An internal clock is provided Operates up to 5MHz Clock Rate and its frequency can be adjusted with an external Two Independent Sections with One Clock capacitor. The LTC6943 can also be driven with an external Tiny SSOP-16 Package CMOS clock. U APPLICATIO S The LTC6943, when used with low clock frequencies, provides ultra precision DC functions without requiring Ultra Precision Voltage Inverters, Multipliers precise external components. Such functions are and Dividers differential voltage to single-ended conversion, voltage VF and FV Converters inversion, voltage multiplication and division by 2, 3, 4, 5, Sample-and-Hold etc. Current Sources The LTC6943 is manufactured using Linear Technologys Precision Instrumentation Amplifiers TM enhanced LTCMOS silicon gate process, and it is func- , LTC and LT are registered trademarks of Linear Technology Corporation. LTCMOS is a trademark of Linear Technology Corporation. tionally compatible with the LTC1043. TYPICAL APPLICATIO Precision Voltage Controlled Current Source with Ground Referred Input and Output 5V Precision Current Sensing in Supply Rails INPUT 3 5 + 0V TO 3.7V 1 E LTC2050 I 4 POSITIVE OR 2 NEGATIVE RAIL R SHUNT 0.68F 1/2 LTC6943 11 12 5V 1k 3 10 1/2 LTC6943 7 6 E 1F 1F E I = R SHUNT 9 9 1F 1F 1k 10 6 7 12 11 V IN I = OUT 14 15 1000 0.01F 15 14 0.001F 6943 TA01b OPERATES FROM A SINGLE 5V SUPPLY 6943 TA01a 6943f 1 U ULTC6943 UUW ABSOLUTE AXI U RATI GS PACKAGE/ORDER I FOR ATIO (Note 1) ORDER PART Supply Voltage ........................................................ 18V TOP VIEW + NUMBER + Input Voltage at Any Pin .......... 0.3V V V + 0.3V CB 1 IN 16 S3B Operating Temperature Range CB 2 15 V LTC6943CGN + (Note 2) ............................................ 40C to 125C V 3 14 C OSC LTC6943IGN S2B 4 13 Specified Temperature Range S4B LTC6943HGN S1B 5 12 S4A (Note 2) .............................................40C to 125C S1A 6 11 S3A GN PART Storage Temperature Range ................. 65C to 150C S2A 7 10 CA MARKING Lead Temperature (Soldering, 10 sec).................. 300C + SHA 8 9 CA 6943C GN PACKAGE 6943I 16-LEAD NARROW PLASTIC SSOP T = 125C, = 110C/W JMAX JA 6943H Consult LTC Marketing for parts specified with wider operating temperature ranges. ELECTRICAL CHARACTERISTICS The denotes specifications which apply over the full operating temperature + range, otherwise specifications are at T = 25C. V = 10V, V = 0V A LTC6943C LTC6943I LTC6943H SYMBOL PARAMETER CONDITIONS MIN TYP MAX MIN TYP MAX UNITS I Power Supply Current Pin 14 Connected High or Low 40 60 40 60 A S 90 90 A C (Pin 14 to V ) = 100pF 80 150 80 150 A OSC 170 170 A I OFF Leakage Current Any Switch, Test Circuit 1 (Note 3) 6 100 6 100 pA I 40 200 nA R ON Resistance Test Circuit 2, V = 7V, 1 = 0.5mA 240 400 240 400 ON IN + V = 10V, V = 0V 700 700 R ON Resistance Test Circuit 2, V = 3.1V, 1 = 0.5mA 400 700 400 700 ON IN + V = 5V, V = 0V 11k f Internal Oscillator Frequency C (Pin 14 to V ) = 0pF 185 185 kHz OSC OSC C (Pin 14 to V ) = 100pF 20 30 50 20 30 50 kHz OSC Test Circuit 3 12 75 10 75 kHz + I Pin Source or Sink Current Pin 14 at V or V 40 70 40 70 A OSC 100 100 A Break-Before-Make Time 25 25 ns Clock to Switching Delay C Pin Externally Driven 75 75 ns OSC f Maximum External CLK Frequency C Pin Externally Driven with CMOS Levels 5 5 MHz M OSC + CMRR Common Mode Rejection Ratio V = 5V, V = 5V, 5V < V < 5V 120 120 dB CM DC to 400Hz Note 1: Absolute Maximum Ratings are those values beyond which the life to 85C but it is not tested or QA sampled at these temperatures. of a device may be impaired. The LTC6943IGN is guaranteed to meet specified performance from 40C Note 2: All versions of the LTC6943 are guaranteed functional over the to 85C. The LTC6943HGN is guaranteed to meet specified performance operating temperature range of 40C to 125C. The LTC6943CGN is from 40C to 125C. guaranteed to meet 0C to 70C specifications and is designed, Note 3: OFF leakage current at 25C is guaranteed by design and it is not characterized and expected to meet the specified performance from 40C 100% tested in production. 6943f 2 U WWW