LTC1274/LTC1277 12-Bit, 10mW, 100ksps ADCs with 1A Shutdown DESCRIPTIO FEATURES Low Power Dissipation: 10mW The LTC 1274/LTC1277 are 8s sampling 12-bit A/D Sample Rate: 100ksps converters which draw only 2mA (typ) from single 5V or Samples Inputs Beyond Nyquist, 72dB S/(N + D) 5V supplies. These easy-to-use devices come complete and 82dB THD at f = 100kHz with a 2s sample-and-hold, a precision reference and an IN Single Supply 5V or 5V Operation internally trimmed clock. Unipolar and bipolar conversion Power Shutdown to 1A in Sleep Mode modes add to the flexibility of the ADCs. 180A Nap Mode (LTC1277) with Instant Wake-Up Two power-down modes are available in the LTC1277. In Internal Reference Can Be Overdriven Nap mode, the LTC1277 draws only 180A and the instant Internal Synchronized Clock wake-up from Nap mode allows the LTC1277 to be pow- 0V to 4.096V or 2.048V Input Ranges (1mV/LSB) ered down even during brief inactive periods. In Sleep 24-Lead SO Package mode only 1A will be drawn. A REFRDY signal is used to show the ADC is ready to sample after waking up from PPLICATI S A Sleep mode. The LTC1274 also provides the Sleep mode and REFRDY signal. Battery-Powered Portable Systems High Speed Data Acquisition for PCs The A/D converters convert 0V to 4.096V unipolar inputs Digital Signal Processing from a single 5V supply or 2.048V bipolar inputs from Multiplexed Data Acquisition Systems 5V supplies. Audio and Telecom Processing The LTC1274 has a single-ended input and a 12-bit Spectrum Analysis parallel data format. The LTC1277 offers a differential input and a 2-byte read format. The bipolar mode is formatted as 2s complement for the LTC1274 and offset binary for the LTC1277. , LTC and LT are registered trademarks of Linear Technology Corporation. TYPICAL APPLICATI Single 5V Supply, 10mW, 100kHz, 12-Bit ADC Supply Current vs Sample Rate with Sleep and Nap Modes LTC1277 5V 10000 1 24 + ANALOG C = 4.7F A V IN DD REF DIFFERENTIAL INPUTS + 2 23 A V (0V TO 4.096V) IN SS WITHOUT SLEEP OR NAP 10F 0.1F 3 22 2.42V V BUSY REF P 1000 V OUTPUT REF + 4 21 AGND CS CONTROL 0.1F 10F NAP MODE 5 20 LINES REFRDY RD 6 19 SLEEP CONVST 100 7 18 NAP HBEN OPTIONAL 3V SUPPLY NAP = REFRDY 8 17 TO INTERFACE WITH 3V D7 V LOGIC (SLEEP MODE) 9 16 PROCESSOR D6 D0/8 10 10 15 NAP = 5V D5 D1/9 (SLEEP MODE) 8-BIT 11 14 D4 D2/10 PARALLEL 12 13 BUS DGND D3/11 1 0.1 1 10 100 1k 10k 100k LTC1274/77 TA01 SAMPLE RATE (Hz) LTC1274/77 TA02 1 SUPPLY CURRENT (A) UO UO ULTC1274/LTC1277 ABSOLUTEXAI U RATI GS (Notes 1, 2) Supply Voltage (V ) ................................................ 7V Digital Output Voltage DD Negative Supply Voltage (V ) Unipolar Operation ................... 0.3V to V + 0.3V SS DD Bipolar Operation Only .......................... 6V to GND Bipolar Operation...................... 0.3V to V + 0.3V DD Total Supply Voltage (V to V ) Power Dissipation............................................. 500mW DD SS Bipolar Operation Only ....................................... 12V Operating Temperature Range Analog Input Voltage (Note 3) Commercial ............................................ 0C to 70C Unipolar Operation ................... 0.3V to V + 0.3V Industrial ........................................... 40C to 85C DD Bipolar Operation............... V 0.3V to V + 0.3V Storage Temperature Range ................ 65C to 150C SS DD Digital Input Voltage (Note 4) Lead Temperature (Soldering, 10 sec)................. 300C Unipolar Operation .............................. 0.3V to 12V Bipolar Operation.......................... V 0.3V to 12V SS PACKAGE/ORDER I FOR ATIO TOP VIEW TOP VIEW ORDER ORDER + A 1 V A 1 V 24 24 IN DD PART NUMBER IN DD PART NUMBER V 2 23 V A 2 V 23 REF SS IN SS AGND 3 22 BUSY V 3 BUSY 22 REF LTC1274CSW LTC1277CSW D11 (MSB) 4 21 CS AGND 4 CS 21 LTC1274ISW LTC1277ISW D10 5 20 RD REFRDY 5 RD 20 D9 6 19 CONVST SLEEP 6 CONVST 19 D8 7 18 SLEEP NAP 7 HBEN 18 D7 8 17 REFRDY D7 8 V 17 LOGIC D6 9 16 D0 D6 9 D0/8 16 D5 10 15 D1 D5 10 D1/9 15 D4 11 14 D2 D4 11 D2/10 14 DGND 12 13 D3 DGND 12 D3/11 13 (D11 = MSB) SW PACKAGE SW PACKAGE 24-LEAD PLASTIC SO WIDE 24-LEAD PLASTIC SO WIDE T = 110C, = 130C/W T = 110C, = 130C/W JMAX JA JMAX JA Consult factory for Military grade parts. With Internal Reference (Notes 5, 6) CO VERTERCCHARA TERISTICS PARAMETER CONDITIONS MIN TYP MAX UNITS Resolution (No Missing Codes) 12 Bits Integral Linearity Error (Note 7) 1 LSB Differential Linearity Error 1 LSB Unipolar Offset Error 6 LSB 8 LSB Bipolar Offset Error (Note 8) 8 LSB 10 LSB Gain Error 20 LSB Gain Error Tempco I = 0 10 45 ppm/C OUT(REF) 2 U U WU U W W W