LTC1099 High Speed 8-Bit A/D Converter with Built-In Sample-and-Hold FEATURES DESCRIPTIO n Built-In Sample-and-Hold The LTC 1099 is a high speed microprocessor compatible n No Missing Codes 8-bit analog-to-digital converter (A/D). An internal sample- n No User Trims Required and-hold (S/H) allows the A/D to convert inputs up to the n All Timing Inputs Edge Sensitive for Easy Processor full Nyquist limit. With a conversion rate of 2.5m s, this Interface allows 156kHz 5V input signals or slew rates as high as P-P n Fast Conversion Time: 2.5m s 2.5V/m s, to be digitized without the need for an external n Latched Three-State Outputs S/H. n Single 5V Operation Two modes of operation, Read (RD) mode and Write-Read n No External Clock (WR-RD) mode, allow easy interface with processors. All n Overflow Output Allows Cascading timing is internal and edge sensitive which eliminates the n T Input Allows User Adjustable Conversion Time C need for external pulse shaping circuits. The Stand-Alone n 0.3 Wide 20-Pin PDIP (SA) mode is convenient for those applications not involv- U ing a processor. KEY SPECIFICATIO S Data outputs are latched with three-state control to allow n Resolution: 8-Bits easy interface to a processor data bus or I/O port. An n Conversion Time: 2.5m s (RD Mode) overflow output (OFL) is provided to allow cascading for 2.5m s (WR/RD Mode) higher resolution. n Slew Rate Limit (Internal S/H): 2.5V/m s n Low Power: 75mW Max n Total Unadjusted Error LTC1099: 1 LSB LTC1099A: 0.75 LSB , LTC and LT are registered trademarks of Linear Technology Corporation. TYPICAL APPLICATION Infinite Hold Time Sample-and-Hold (T = 240ns) Signal-to-Noise Ratio (SNR) vs Input Frequency ACQ 5V 15V 36 10k T = 25C A T = 2.5s 38 C 12 20 + 14 20 REF V CC 2.5k 40 + + LTC1099 REF V 7 17 1 MODE DB7 B1 42 16 2 DB6 B2 1 18 2 15 3 7 V IN V DB5 44 B3 + IN I O 14 4 DB4 6 B4 6 SAMPLE 5 5 V AM6012 LT1022 OUT 46 WR/RDY DB3 B5 4 6 3 DB2 I B6 O 8 3 7 4 HOLD 48 19 RD DB1 B7 2 8 DB0 B8 13 50 CS REF V GND REF 52 15 17 1 10 100 10k 10 11 INPUT FREQUENCY (kHz) 1099 G08 1099 TA01 15V 1 SIGNAL-TO-NOISE RATIO, SNR (dB) U ULTC1099 ABSOLUTE AXI U RATI GS (Notes 1, 2) Supply Voltage (V ) to GND Voltage ...................... 12V Operating Temperature Range CC Analog and Reference Inputs... 0.3V to (V + 0.3V) LTC1099C/LTC1099AC ............................ 0 C to 70 C CC Digital Inputs .........................................0.3V to 12V LTC1099I/LTC1099AI ..........................40 C to 85 C Digital Outputs ........................ 0.3V to (V + 0.3V) Storage Temperature Range ................. 65 C to 150 C CC Power Dissipation.............................................. 500mW Lead Temperature (Soldering, 10 sec).................. 300 C UUW PACKAGE/ORDER I FOR ATIO TOP VIEW TOP VIEW ORDER PART ORDER PART V 1 20 V 1 20 V IN CC V CC NUMBER NUMBER IN 2 DB0 19 TC 2 19 T DB0 C DB1 3 18 OFL 3 18 OFL DB1 LTC1099CN LTC1099CSW DB2 4 17 DB7 4 17 DB7 DB2 LTC1099ACN DB3 5 16 DB6 5 16 DB6 DB3 LTC1099AIN WR/RDY 6 15 DB5 6 15 DB5 WR/RDY MODE 7 14 DB4 7 14 DB4 MODE RD 8 13 CS 8 13 CS RD + + INT 9 12 REF 9 12 REF INT GND 10 11 REF 10 REF GND 11 SW PACKAGE N PACKAGE 20-LEAD PLASTIC SO 20-LEAD PDIP T = 150 C, q = 130 C/W JMAX JA T = 150 C, q = 100 C/W JMAX JA Consult factory for parts specified with wider operating temperature ranges. CONVERTER CHARACTERISTICS The l denotes the specifications which apply over the full operating + temperature range, otherwise specifications are at T = 25 C. V = 5V, REF = 5V, REF = 0V and T = T to T unless otherwise A CC A MIN MAX noted. LTC1099AI/LTC1099I LTC1099AC/LTC1099C PARAMETER CONDITIONS MIN TYP MAX MIN TYP MAX UNITS Accuracy Total Unadjusted Error (Note 3) LTC1099A l 0.75 0.75 LSB LTC1099 l 1 1 LSB Minimum Resolution (No Missing Codes) l 8 8 Bits Reference Input Input Resistance l 1 3.2 6 2 3.2 4.5 kW + REF Input Voltage Range (Note 4) l REF V REF V V CC CC + + REF Input Voltage Range (Note 4) l GND REF GND REF V Analog Input Input Voltage Range l GND V GND V V CC CC Input Leakage Current CS = V , V = V , GND l 3 3 m A CC IN CC Input Capacitance 60 60 pF Sample-and-Hold Acquisition Time 240 240 ns Aperture Time 110 110 ns Tracking Rate 2.5 2.5 V/m s 2 U U WWW