+ + + + + + LTC2351-12 6 Channel, 12-Bit, 1.5Msps Simultaneous Sampling ADC With Shutdown FEATURES DESCRIPTION n 1.5Msps ADC with 6 Simultaneously Sampled The LTC 2351-12 is a 12-bit, 1.5Msps ADC with six simul- Differential Inputs taneously sampled differential inputs. The device draws n 250ksps Throughput per Channel only 5.5mA from a single 3V supply, and comes in a tiny n 72dB SINAD 32-pin (5mm 5mm) QFN package. A Sleep shutdown n Low Power Dissipation: 16.5mW mode further reduces power consumption to 12W. The n 3V Single Supply Operation combination of low power and tiny package makes the n 2.5V Internal Bandgap Reference, Can be Overdriven LTC2351-12 suitable for portable applications. With External Reference The LTC2351-12 contains six separate differential inputs n 3-Wire SPI-Compatible Serial Interface that are sampled simultaneously on the rising edge of the n Internal Conversion Triggered by CONV CONV signal. These six sampled inputs are then converted n SLEEP (12W) Shutdown Mode at a rate of 250ksps per channel. n NAP (4.5mW) Shutdown Mode n The 83dB common mode rejection allows users to eliminate 0V to 2.5V Unipolar, or 1.25V Bipolar Differential ground loops and common mode noise by measuring Input Range n signals differentially from the source. 83dB Common Mode Rejection n Tiny 32-Pin (5mm 5mm) QFN Package The device converts 0V to 2.5V unipolar inputs differentially, or 1.25V bipolar inputs also differentially, depending on the state of the BIP pin. Any analog input may swing rail-to-rail APPLICATIONS as long as the differential input range is maintained. n Multiphase Power Measurement The conversion sequence can be abbreviated to convert n Multiphase Motor Control fewer than six channels, depending on the logic state of n Data Acquisition Systems the SEL2, SEL1 and SEL0 inputs. n Uninterruptable Power Supplies L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. The serial interface sends out the six conversion results in 96 All other trademarks are the property of their respective owners. clocks for compatibility with standard serial interfaces. Protected by U.S. Patents including 6084440, 6522187. BLOCK DIAGRAM 10F 3V + + + + + + CH5 CH5 CH4 CH4 CH3 CH3 CH2 CH2 CH1 CH1 CH0 CH0 V V CC DD 21 20 19 18 17 16 15 14 12 11 10 9 8 7 6 5 4 24 25 13 OV DD 12-BIT LATCH 0 3V 3 THREE- 12-BIT LATCH 1 S AND H S AND H S AND H S AND H S AND H S AND H STATE 12-BIT LATCH 2 SD0 1.5Msps SERIAL 1 12-BIT ADC 12-BIT LATCH 3 OUTPUT 0.1F 12-BIT LATCH 4 OGND PORT 2 12-BIT LATCH 5 MUX CONV TIMING 30 2.5V LOGIC SCK REFERENCE 32 DGND 31 33 22 23 29 26 27 28 235112 TA01 10F GND V BIP SEL2 SEL1 SEL0 REF 235112fa 1LTC2351-12 ABSOLUTE MAXIMUM RATINGS PIN CONFIGURATION (Notes 1, 2) TOP VIEW Supply Voltage (V , V , OV ) ................................ 4V DD CC DD Analog and V Input Voltages REF 16 15 14 13 12 11 10 9 (Note 3) ................................... 0.3V to (V + 0.3V) DD + CH4 17 8 CH1 Digital Input Voltages ................... 0.3V to (V + 0.3V) DD + CH4 18 7 CH1 Digital Output Voltage .................. 0.3V to (V + 0.3V) DD GND 19 6 GND Power Dissipation ...............................................100mW + CH5 20 5 CH0 33 Operation Temperature Range + CH5 21 4 CH0 LTC2351C-12 ........................................... 0C to 70C GND OV 22 3 DD LTC2351I-12 ........................................40C to 85C V 23 2 OGND REF V 24 1 SDO CC LTC2351H-12 .....................................40C to 125C 25 26 27 28 29 30 31 32 Storage Temperature Range ...................65C to 150C QFN PACKAGE 32-PIN (5mm s 5mm) PLASTIC QFN T = 150C, = 34C/W JMAX JA EXPOSED PAD (PIN 33) IS GND, MUST BE SOLDERED TO PCB ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE LTC2351CUH-12 PBF LTC2351CUH-12 TRPBF 235112 32-Pin (5mm 5mm) Plastic QFN 0C to 70C LTC2351IUH-12 PBF LTC2351IUH-12 TRPBF 235112 32-Pin (5mm 5mm) Plastic QFN 40C to 85C LTC2351HUH-12 PBF LTC2351HUH-12 TRPBF 235112 32-Pin (5mm 5mm) Plastic QFN 40C to 125C Consult LTC Marketing for parts speci ed with wider operating temperature ranges. *The temperature grade is identi ed by a label on the shipping container. Consult LTC Marketing for information on non-standard lead based nish parts. For more information on lead free part marking, go to: