LT1635 Micropower Rail-to-Rail Op Amp and Reference U DESCRIPTION FEATURES ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ Guaranteed Operation at 1.2V Op Amp and Reference on Single Chip Micropower: 130µA Supply Current Industrial Temperature Range SO-8 Packages Rail-to-Rail Output High Output Current: 25mA Min Output Drives 1000pF Capable of Floating Mode Operation Specified for 5V and ±5V Supplies Low Reference Drift: 30ppm/°C Industry Standard LM10 Pinout U APPLICATIONS ■ ■ ■ ■ The input common mode range of the op amp includes ground and incorporates phase reversal protection to prevent false outputs from occurring when the input is below the negative supply. The rail-to-rail output stage can swing to within 15mV of each rail with no load and can swing to within 250mV of each rail while delivering 10mA of output current. The gain bandwidth of the op amp is 175kHz and it is unitygain stable with up to 1000pF load capacitance. The 0.2V reference is referred to V – and includes a buffer amplifier to enhance flexibility. The reference and buffer combine to achieve a drift of 30ppm/°C, a line regulation of 20ppm/V and a load regulation of 150ppm/mA. Battery- or Solar-Powered Systems Portable Instrumentation Sensor Conditioning Precision Current Regulators Precision Voltage Regulators Battery Level Indicator Thermocouple Transmitter The LT1635 is available in 8-pin PDIP and SO packages, and has the industry standard LM10 pinout. , LTC and LT are registered trademarks of Linear Technology Corporation. U ■ The LT ®1635 is a new analog building block that includes a rail-to-rail output op amp, a precision reference and reference buffer. The device operates from supplies as low as a single 1.2V or up to ±5V, yet it consumes only 130µA of supply current. TYPICAL APPLICATION 0V to 5V Regulator Typical Distribution of Input Offset Voltage C1 0.01µF 25 VS = 5V, 0V TA = 25°C 3 VOUT ADJ – + 7 6 LT1635 4 VOUT 0V TO 5V PERCENT OF UNITS 2 R2 3.9k 20 VIN > 5.2V R1 100k 15 10 5 8 1 0 – 1.0 R3 5k 1635 TA01 – 0.6 0.2 0.6 – 0.2 INPUT OFFSET VOLTAGE (mV) 1.0 1635 TA02 1 LT1635 W U U W W W Total Supply Voltage (V + to V –) .............................. 14V Input Differential Voltage ......................................... 14V Input Current ...................................................... ±25mA Output Short-Circuit Duration .......................Continuous Operating Temperature Range (Note 1) .............................................. – 40°C to 85°C Junction Temperature ........................................... 150°C Storage Temperature Range ................. – 65°C to 150°C Lead Temperature (Soldering, 10 sec).................. 300°C U ABSOLUTE MAXIMUM RATINGS PACKAGE/ORDER INFORMATION ORDER PART NUMBER TOP VIEW REFOUT 1 – 8 REF FB OP AMP IN (–) 2 + 7 V+ OP AMP IN (+) 3 – 6 OP AMP OUT + + V– 4 N8 PACKAGE 8-LEAD PDIP LT1635CN8 LT1635CS8 LT1635IN8 LT1635IS8 5 BALANCE S8 PACKAGE 8-LEAD PLASTIC SO S8 PART MARKING TJMAX = 150°C, θJA = 130°C/ W (N8) TJMAX = 150°C, θJA = 190°C/ W (S8) 1635 1635I Consult factory for Military grade parts. ELECTRICAL CHARACTERISTICS 5V OP AMP: VS = 5V, 0V; VCM = VOUT = 2.5V, TA = 25°C, unless otherwise noted. (Note 1) SYMBOL PARAMETER VOS Input Offset Voltage CONDITIONS MIN 0°C ≤ TA ≤ 70°C – 40°C ≤ TA ≤ 85°C ● ● Input Offset Voltage Drift – 40°C ≤ TA ≤ 85°C (Note 3) ● VOS ADJ Offset Voltage Adjust Range Positive Adjust Negative Adjust ● ● IOS Input Offset Current IB Input Bias Current Input Noise Voltage 6 – 1.4 TYP MAX 0.3 0.5 1.3 1.6 1.8 mV mV mV 3.0 7.0 µV/°C 8 –2 UNITS mV mV ● 0.2 0.6 nA ● 2.0 2.5 4.0 5.0 nA nA 0.1Hz to 10Hz 1 µVP-P en Input Noise Voltage Density f = 1kHz 50 nV/√Hz in Input Noise Current Density f = 1kHz 0.05 pA/√Hz RIN Input Resistance Differential Common Mode, VCM = 0V to 4V Input Voltage Range CMRR AVOL Common Mode Rejection Ratio ● 7 ● 0 ● 92 85 110 97 dB dB ● ● ● 100 45 35 450 200 150 V/mV V/mV V/mV 15 8 25 20 V/mV V/mV V/mV VCM = 0V to 4V Large-Signal Voltage Gain VO = 200mV to 4.5V, No Load VO = 200mV to 4.5V, RL = 1.1k VO = 200mV to 4.5V, RL = 500Ω Shunt Gain IOUT = 0.1mA to 5mA VO = 1.5V to 6.45V (Note 4) ● VOL Output Voltage Swing Low VS = 5V, No Load VS = 5V, ISINK = 5mA VS = 5V, ISINK = 10mA ● ● ● VOH Output Voltage Swing High VS = 5V, No Load VS = 5V, ISOURCE = 5mA VS = 5V, ISOURCE = 10mA ● ● ● 2 25 6 4 2 125 200 4.975 4.65 4.55 MΩ GΩ 4.985 4.8 4.75 10 250 500 V mV mV mV V V V LT1635 ELECTRICAL CHARACTERISTICS 5V OP AMP: VS = 5V, 0V; VCM = VOUT = 2.5V, TA = 25°C, unless otherwise noted. (Note 1) SYMBOL PARAMETER CONDITIONS ISC Short-Circuit Current VS = 5V, Short to GND VS = 5V, Short to VCC PSRR Power Supply Rejection Ratio VS = 1.2V to 12V, VCM = VO = 0.2V Minimum Operating Supply Voltage IS (Note 2) MIN TYP ● ● 25 25 40 40 mA mA ● 93 90 100 97 dB dB Gain Bandwidth Product f = 1kHz SR Slew Rate AV = – 1, RL = ∞ UNITS ● 1.1 1.2 V ● 130 150 200 260 µA µA Supply Current GBW MAX 175 kHz 0.045 V/µs 5V REFERENCE: VS = 5V, 0V; TA = 25°C, unless otherwise noted. (Note 1) SYMBOL PARAMETER CONDITIONS VREF Feedback Sense Voltage Voltage at Pin 1 with Pin 1 Connected to Pin 8 (Note 5) ● TC VREF Reference Drift (Note 3) Feedback Current Current into Pin 8 Line Regulation Load Regulation Reference Amplifier Gain 0 ≤ IREF ≤ 1mA, VREF = 200mV VS = 1.2V to 5V VS = 1.3V to 5V (Note 2) MIN TYP MAX UNITS 189 200 211 mV ● 30 100 ppm/°C ● 3.5 5.0 10 15 nA nA ● 20 30 35 55 ppm/V ppm/V ● 150 200 300 500 ppm/mA ppm/mA IREF = 0 to 1mA VO = 0.2V to 3.5V ● 45 25 90 50 V/mV V/mV MIN TYP MAX 0.3 0.5 1.5 1.9 2.1 mV mV mV 4.5 10.0 µV/°C ±5V OP AMP: VS = ±5V; VCM = VOUT = 0V, TA = 25°C, unless otherwise noted. (Note 1) SYMBOL PARAMETER VOS Input Offset Voltage CONDITIONS 0°C ≤ TA ≤ 70°C – 40°C ≤ TA ≤ 85°C ● ● Input Offset Voltage Drift 0°C ≤ TA ≤ 85°C (Note 3) ● VOS ADJ Offset Voltage Adjust Range Positive Adjust Negative Adjust ● ● IOS Input Offset Current IB Input Bias Current 6 – 1.4 8 –2 UNITS mV mV ● 0.2 0.6 nA ● 2.0 2.5 4 5 nA nA Input Noise Voltage 0.1Hz to 10Hz 1 µVP-P en Input Noise Voltage Density f = 1kHz 50 nV/√Hz in Input Noise Current Density f = 1kHz 0.05 pA/√Hz RIN Input Resistance Differential Common Mode, VCM = – 5V to 4V Input Voltage Range CMRR Common Mode Rejection Ratio ● 7 ● –5 ● 94 91 VCM = – 5V to 4V 35 9 MΩ GΩ 4 115 110 V dB dB 3 LT1635 ELECTRICAL CHARACTERISTICS ±5V OP AMP: VS = ±5V; VCM = VOUT = 0V, TA = 25°C, unless otherwise noted. (Note 1) SYMBOL PARAMETER CONDITIONS AVOL Large-Signal Voltage Gain VO = – 4.5V to 4.5V, No Load VO = – 4.5V to 4.5V, RL = 1.1k VO = – 4.5V to 4.5V, RL = 500Ω VO Output Voltage Swing VS = ±5V, No Load VS = ±5V, ISINK = 5mA VS = ±5V, ISINK = 10mA ISC Short-Circuit Current VS = ±5V PSRR Power Supply Rejection Ratio VS = ±1V to ±6V, VCM = VO = 0V MIN TYP ● ● ● 175 15 10 300 100 60 ● ● ● ±4.975 ±4.65 ±4.5 ±4.985 ±4.75 ±4.6 mV mV mV ±25 ±40 mA 90 88 100 98 dB dB ● IS Supply Current 135 160 ● MAX UNITS V/mV V/mV V/mV 215 280 µA µA GBW Gain Bandwidth Product f = 1kHz 175 kHz SR Slew Rate AV = –1, RL = ∞ 0.05 V/µs ±5V REFERENCE: VS = ±5V, TA = 25°C, unless otherwise noted. (Note 1) SYMBOL PARAMETER CONDITIONS VREF Feedback Sense Voltage Voltage at Pin 1 with Pin 1 Connected to Pin 8 (Note 5) ● TC VREF Reference Drift (Note 3) Feedback Current Current into Pin 8 Line Regulation Load Regulation Reference Amplifier Gain 0 ≤ IREF ≤ 1mA, VREF = 200mV VS = ±0.6V to ±5V VS = ±0.65V to ±5V (Note 2) TYP MAX UNITS 189 200 211 mV ● 40 120 ppm/°C ● 3.5 5.0 10 15 nA nA ● 20 30 25 55 ppm /V ppm/V ● 150 200 300 500 ppm/mA ppm/mA IREF = 0 to 1mA VO = 0.2V to 8.5V VS = 10V, 0V The ● denotes specifications that apply over the full operating temperature range. Note 1: The LT1635C is guaranteed to operate over the commercial temperature range of 0°C to 70°C. It is designed, characterized and expected to meet these extended temperature limits, but is not tested at – 40°C and 85°C. The LT1635I is guaranteed to meet the industrial temperature range. Note 2: The LT1635 op amp operates on a 1.2V supply over the full industrial temperature range with an input common mode of 0V to 0.2V. The minimum supply voltage for the reference to operate properly over this temperature range is 1.3V. 4 MIN ● 45 25 90 50 V/mV V/mV Note 3: This parameter is not 100% tested. Temperature coefficient is measured by dividing the change in output voltage by specified temperature range. Note 4: Shunt gain defines the operation in floating applications when the output is connected to the V + terminal and input common mode is referred to V –. Note 5: If part is stored outside of the specified temperature range, the output may shift due to hysteresis. LT1635 U W TYPICAL PERFORMANCE CHARACTERISTICS Input Bias and Offset Currents vs Temperature 160 140 –1 0 VS = 5V, 0V VS = 5V, 0V IOS 50 0 TA = 25°C 120 100 TA = 125°C 80 60 100 Input Bias Current vs Common Mode Voltage INPUT BIAS CURRENT (nA) SUPPLY CURRENT (µA) TA = – 55°C 180 OFFSET CURRENT (pA) 220 BIAS CURRENT (nA) Supply Current vs Supply Voltage 200 Op Amp 2 6 7 4 5 8 SUPPLY VOLTAGE (V) 3 9 10 IB –2 –3 –50 –25 50 25 0 75 TEMPERATURE (°C) 1635 G01 100 80 4 5 6 TIME (SEC) 7 8 9 70 60 50 40 25 CHANGE IN INPUT OFFSET VOLTAGE (V) PERCENT OF UNITS 15 10 5 10 100 FREQUENCY (Hz) –4 –2 0 2 TCVOS (µV/°C) 4 0.3 0.2 0.1 1 1000 6 1635 G07 10 100 FREQUENCY (Hz) 1635 G06 200 140 0 120 – 200 TA = 125°C – 400 TA = 25°C – 600 TA = – 55°C – 800 0 1 TOTAL SUPPLY VOLTAGE (V) 1000 Turn-On Drift of Three Typical Units –1000 –6 0.4 Minimum Supply Voltage 20 VS = ± 2.5V TA = 25°C 1635 G05 Typical Distribution of Offset Voltage Drift with Temperature 4 0 1 10 VS = 5V, 0V 0 2 3 1 COMMON MODE VOLTAGE (V) Input Noise Current vs Frequency VS = ± 2.5V TA = 25°C 1635 G04 0 –4 0.5 CHANGE IN OFFSET VOLTAGE (µV) 3 –3 1635 G03 INPUT NOISE CURRENT DENSITY (pA/√Hz) INPUT NOISE VOLTAGE DENSITY (nV/√Hz) NOISE VOLTAGE (1µV/DIV) 2 TA = – 55°C –5 –1 125 30 1 TA = 25°C –2 Noise Voltage Density vs Frequency VS = ± 5V TA = 25°C TA = 125°C 1635 G02 0.1Hz to 10Hz Noise Voltage 0 –1 2 1635 G08 100 80 60 40 20 VS = ± 5V TA = 25°C 0 0 1 7 8 9 4 5 6 2 3 TIME AFTER POWER ON (MINUTES) 10 1635 G09 5 LT1635 U W TYPICAL PERFORMANCE CHARACTERISTICS Gain Phase vs Frequency VS = ± 2.5V TA = 25°C 100 VS = ± 2.5V TA = 25°C 50 PHASE MARGIN 70° 40 VOLTAGE GAIN (dB) 80 60 40 20 30 120 50 VS = ± 5V RL = ∞ TA = 25°C 140 PHASE 160 20 180 10 200 220 0 GAIN – 10 240 –20 260 AV = 5 40 AV = 10 AV = 1 30 20 10 0 – 30 1 10 100 1k FREQUENCY (Hz) 350 GAIN-BANDWIDTH PRODUCT (kHz) FALLING SLEW RATE 0.07 0.06 RISING SLEW RATE 0.04 – 50 – 25 50 25 75 0 TEMPERATURE (°C) 100 125 75 1M VS = 5V, 0V 70 300 PHASE MARGIN 250 65 200 60 GAIN-BANDWIDTH PRODUCT 150 100 –50 –25 50 0 25 75 TEMPERATURE (°C) PHASE MARGIN (DEG) 0.08 TA = – 55°C TA = 25°C 55 100 50 125 TA = 125°C 100k 0.1 1 10 100 1000 LOAD RESISTANCE TO GROUND (kΩ) 1635 G15 1635 G14 1635 G13 Large-Signal Transient Response VS = ±5V Shunt Gain 10000 Voltage Gain vs Load Resistance VS = ± 2.5V VS = ± 5V 0.09 100 1000 CAPACITIVE LOAD (pF) 1635 G12 Gain-Bandwidth Product and Phase Margin vs Temperature Slew Rate vs Temperature 0.05 10 1635 G11 1635 G10 0.10 0 280 1000 100 FREQUENCY (kHz) 10 10k 100k 1M VOLTAGE GAIN (V/V) – 20 0.01 0.1 SLEW RATE (V/µs) 60 100 PHASE SHIFT (DEG) VOLTAGE GAIN (dB) Capacitive Load Handling 60 OVERSHOOT (%) Voltage Gain vs Frequency 120 Op Amp Large-Signal Transient Response VS = 5V, 0V 0.5 IOUT = 20mA 0.3 0V 1V/DIV 0.4 2V/DIV INPUT VOLTAGE CHANGE (mV) TA = 25°C + + 0.2 VIN 0V VOUT – IOUT – 0.1 200µs/DIV IOUT = 1mA AV = 1, NO LOAD INPUT 8VP-P 0 0 1 2 6 4 3 5 OUTPUT VOLTAGE (V) 7 8 1635 G16 6 1635 G17 100µs/DIV AV = 1, NO LOAD INPUT PULSE 0V TO 4V 1635 G18 LT1635 U W TYPICAL PERFORMANCE CHARACTERISTICS Output Saturation Voltage vs Input Overdrive Output Saturation Voltage vs Load Current (Output Low) 1000 OUTPUT HIGH 12 10 8 6 4 OUTPUT LOW 2 5 0 10 20 25 15 INPUT OVERDRIVE (mV) TA = 25°C 100 TA = 125°C TA = – 55°C 10 1 0.001 30 0.01 0.1 1 SINKING LOAD CURRENT (mA) Common Mode Range vs Temperature COMMON MODE REJECTION RATIO (dB) COMMON MODE RANGE (V) 120 V + – 0.5 V+ – 1 V– V – – 0.5 100 100 125 0.01 0.1 1 SOURCING LOAD CURRENT (mA) 60 40 20 1635 G21 120 100 1k FREQUENCY (Hz) POSITIVE SUPPLY 80 NEGATIVE SUPPLY 60 40 20 100k 10k VS = ± 2.5V TA = 25°C 100 0 10 10 Power Supply Rejection Ratio vs Frequency 80 1 0.1 1 10 100 1k FREQUENCY (Hz) 10k 100k 1635 G24 1635 G23 Small-Signal Transient Response VS = ±5V Output Impedance vs Frequency Small-Signal Transient Response VS = 5V, 0V VS = ± 2.5V TA = 25°C AV = 100 AV = 10 10mV/DIV OUTPUT IMPEDANCE (Ω) 0.01 0.001 10 VS = ±2.5V TA = 25°C 1635 G22 1000 TA = – 55°C 0 50 25 75 0 TEMPERATURE (°C) TA = 125°C 0.1 Common Mode Rejection Ratio vs Frequency V+ 10000 TA = 25°C 1635 G20 1635 G19 V– – 1 – 50 – 25 VS = ± 2.5V VOD = 30mV AV = 1 100 0V 10mV/DIV 0 1 VS = ± 2.5V VOD = 30mV POWER SUPPLY REJECTION RATIO (dB) 14 Output Saturation Voltage vs Load Current (Output High) OUTPUT SATURATION VOLTAGE (V) VS = ± 2.5V, NO LOAD TA = 25°C OUTPUT SATURATION VOLTAGE (mV) OUTPUT SATURATION VOLTAGE (mV) 16 Op Amp 10 50µs/DIV 1 0.1 1 10 100 FREQUENCY (kHz) 1000 AV = 1 CL = 15pF 1635 G26 50µs/DIV 1635 G27 AV = 1 CL = 15pF INPUT 50mV TO 100mV 1635 G25 7 LT1635 U W TYPICAL PERFORMANCE CHARACTERISTICS Typical Distribution of Initial Accuracy 18 200 VS = 5V, 0V VS = 5V, 0V TA = 25°C VS = 5V, 0V TA = 25°C 207 REFERENCE OUTPUT (mV) 16 PERCENT OF UNITS Load Regulation Line Regulation 208 14 12 10 8 6 REFERENCE CHANGE (ppm) 20 Reference 206 TA = – 55°C 205 TA = 25°C 204 TA = 125°C 203 202 0 – 200 – 400 4 201 2 200 0 206 204 196 200 202 198 REFERENCE VOLTAGE (mV) 2 4 8 10 6 SUPPLY VOLTAGE (V) 12 Reference Output vs Temperature of Two Typical Units OUTPUT SATURATION VOLTAGE (V) REFERENCE OUTPUT (mV) 204 203 202 25 50 75 VS = 5V, 0V 1.4 VS = 5V, 0V TA = 25°C 100 1.3 80 1.2 1.1 TA = – 55°C 1.0 TA = 25°C 0.9 60 40 20 0.8 0 TA = 125°C 0.7 – 20 0.6 – 40 0.5 125 100 Reference Amplifier Gain 120 1.5 VS = ±5V 0 1 3 2 1 SOURCING CURRENT (mA) TEMPERATURE (°C) 1635 G31 10 W OUTPUT REFERENCE FEEDBACK 6 V+ 8 7 BALANCE INPUTS – 5 – OP AMP 3 REF AMP + + 200mV REFERENCE REFERENCE OUTPUT 1635 BD V– 8 1 + 4 100 1k 10k 100k FREQUENCY (Hz) 1M 10M 1635 G33 1635 G32 BLOCK DIAGRA 2 4 1635 G30 Output Saturation vs Load Current (Sourcing) 205 0 2 1 3 SOURCING CURRENT (mA) 0 1635 G29 1635 G28 201 –50 –25 – 600 14 GAIN (dB) 0 194 LT1635 U U W U APPLICATIONS INFORMATION The LT1635 is fully specified with V + = 5V, V – = 0V and VCM = 2.5V. The op amp offset voltage is internally trimmed to a minimum value at these supply voltages. A unique feature of this device is that it operates from a single 1.2V supply up to ±5V. A full set of specifications is provided at ±5V supply voltages. The positive supply pin of the LT1635 should be bypassed with a small capacitor (about 0.1µF), as well as the negative supply pin when using split supplies. should be taken to keep the output from saturating. For example, a 1mV input signal will cause the amplifier to set up in its linear region in the gain 100 configuration as shown in Figure 2a. However, 1mV is not enough to make the amplifier function properly in the voltage follower mode (Figure 2b). 99R Op Amp The LT1635 is fully specified for single supply operation, i.e., when the negative supply is 0V. Input common mode range of the op amp includes ground and the output swings within a few millivolts of ground while sinking current. The input stage of the op amp incorporates phase reversal protection to prevent false outputs from occurring when the input is below the negative supply. Protective resistors have been included in the input leads so that current does not become excessive when the inputs are forced below the negative supply. The op amp also includes an offset nulling feature, this is accomplished by connecting the BALANCE pin (Pin 5) to a variable voltage derived from the reference output. The offset adjust range is asymmetrical, typically – 2mV to 8mV. At room temperature the input offset voltage of the LT1635 is within the null range, thus the offset voltage can be adjusted to zero. Figure 1 shows the standard offset adjustment. V+ 2 – 6 + 1 – – LT1635 OP AMP 1mV + LT1635 OP AMP 100mV 1mV + OUTPUT SATURATED ≈ 2mV 1635 F02 (a) (b) Figure 2. Gain 100 Amplifier and Voltage Follower Distortion There are two main contributors of distortion in op amps: distortion caused by nonlinear common mode rejection and output crossover distortion as the output transitions from sourcing to sinking current. The common mode rejection ratio of the LT1635 is very good, typically 110dB. Therefore, as long as the input operates in normal common mode range, there will be very little common mode induced distortion. Crossover distortion will increase as the output load resistance decreases. For the lowest distortion, the LT1635 should be operated with the output always sourcing current. Reference 4 LT1635 3 5V 5V R 8 5 VREF R1 10k V– 1635 F01 Figure 1. Standard Offset Adjustment Output The output voltage swing of the LT1635 is a function of input overdrive as shown in the typical performance curves. When monitoring voltages within 15mV of either rail, gain The reference of the LT1635 consists of a 200mV precision bandgap and a reference amplifier. As shown in the block diagram, the 0.2V precision bandgap is referred to V – and is internally connected to the noninverting input of the reference amplifier. This configuration offers great flexibility in that the reference voltage can be amplified or the reference amplifier can be used as a comparator. Unlike the op amp, the output of the reference amplifier can only swing within 0.8V (typ) of the positive rail. To guarantee that the reference amplifier does not saturate over the industrial temperature range, the minimum operating supply should be 1.3V. The reference amplifier can source 2mA of load current and can sink 10µA over the industrial temperature range. 9 LT1635 U TYPICAL APPLICATIONS Low Voltage Regulator Best Regulation VIN > 6V C1 0.01µF VIN > 3.2V R1 28k – 3 + 7 6 LT1635 2 – 3 + VOUT 5V 4 8 7 1 6 LT1635 R2 2k 2 VOUT 3V 4 R2 48k + 8 1 R1 2k OPTIONAL* 1635 TA04 *USE ELECTROLYTIC OUTPUT CAPACITORS 1635 TA03 2-Terminal Current Regulator + 2 – 3 + IOUT = Shunt Regulator C1* 0.01µF (R2 + R3)VREF (R1)(R3) 7 R2 6 LT1635 VOUT = 1 + R2 VREF R1 4 1 2 – 3 + 8 R1 ( ) + 7 6 LT1635 R2 R3 R1 – 4 1 8 1635 TA05 – *REQUIRED FOR CAPACITIVE LOADING Negative Regulator 1635 TA06 6V Battery-Level Indicator + GROUND R2 49.9k 1% + 2 – 3 + 7 6 LT1635 4 C1 47µF ELECT R1 680k VOUT – 5V R4 1.5k R3 680k 2 – 3 + D1 7 8 R2 12k R1 2k 1% 4 8 1 – VIN ≤ – 5.5V 1635 TA07 10 6 LT1635 1 Q1 2N3904 LED DIMS BELOW 7V 1635 TA08 LT1635 W W SI PLIFIED SCHEMATICS Op Amp + 7 V Q21 Q28 C2 Q20 R1 6k Q1 2 R2 6k INPUTS Q13 Q19 Q2 3 6 OUTPUT Q15 Q26 Q7 Q4 300k Q3 Q5 5 Q17 Q14 Q6 Q27 Q18 Q16 Q24 Q25 BALANCE 4 V– + 1635 SSOA C1 Reference V+ 7 REF FB 8 1 REFOUT × 16 ×1 V– 4 1635 SSREF U PACKAGE DESCRIPTION Dimensions in inches (millimeters) unless otherwise noted. N8 Package 8-Lead PDIP (Narrow 0.300) (LTC DWG # 05-08-1510) 0.300 – 0.325 (7.620 – 8.255) 0.009 – 0.015 (0.229 – 0.381) ( +0.025 0.325 –0.015 +0.635 8.255 –0.381 ) 0.045 – 0.065 (1.143 – 1.651) 0.130 ± 0.005 (3.302 ± 0.127) 0.065 (1.651) TYP 0.005 (0.127) MIN 0.400* (10.160) MAX 8 7 6 5 1 2 3 4 0.255 ± 0.015* (6.477 ± 0.381) 0.125 (3.175) MIN 0.018 ± 0.003 0.100 ± 0.010 (0.457 ± 0.076) (2.540 ± 0.254) *THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.010 INCH (0.254mm) 0.015 (0.380) MIN Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights. N8 0695 11 LT1635 U TYPICAL APPLICATION 1A Shunt Battery Charger (IDARK = 230µA, VFLOAT = 14V) 100nF 1M 2A 3 1A SOLAR ARRAY + 200mV 8 LT1635 REF 1 7V – 2 + 7 LT1635 OP AMP – 220Ω 6 12V 5A GELCEL TIP121 4 68k 1M 7.5Ω* 10W 2k *DALE HLM-10 1635 TA09 U PACKAGE DESCRIPTION Dimensions in inches (millimeters) unless otherwise noted. S8 Package 8-Lead Plastic Small Outline (Narrow 0.150) (LTC DWG # 05-08-1610) 0.189 – 0.197* (4.801 – 5.004) 0.010 – 0.020 × 45° (0.254 – 0.508) 0.008 – 0.010 (0.203 – 0.254) 0.053 – 0.069 (1.346 – 1.752) 8 0.004 – 0.010 (0.101 – 0.254) 7 6 5 0°– 8° TYP 0.016 – 0.050 0.406 – 1.270 0.014 – 0.019 (0.355 – 0.483) *DIMENSION DOES NOT INCLUDE MOLD FLASH. MOLD FLASH SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE **DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE 0.050 (1.270) BSC 0.150 – 0.157** (3.810 – 3.988) 0.228 – 0.244 (5.791 – 6.197) SO8 0695 1 2 3 4 RELATED PARTS PART NUMBER DESCRIPTION COMMENTS LT1178/LT1179 Dual/Quad 17µA Max, Single Supply Precision Op Amps 70µV VOS Max and 2.5µV/°C Drift Max, 85kHz GBW, 0.04V/µs Slew Rate, Input/Output Common Mode Includes Ground LT1490/LT1491 Dual/Quad Micropower Rail-to-Rail Input and Output Op Amps Single Supply Input Range: – 0.4V to 44V, Micropower 50µA Amplifier, Rail-to-Rail Input and Output, 200kHz GBW LT2178/LT2179 Dual/Quad 17µA Max, Single Supply Precision Op Amps SO-8 and 14-Lead Standard Pinout, 70µV VOS Max, 85kHz GBW LT1078/LT1079 Dual/Quad Micropower, Single Supply Precision Op Amps 70µV VOS Max and 0.4µV/°C Drift, 200kHz GBW, 0.07V/µs Slew Rate, Input/Output Common Mode Includes Ground LT2078/LT2079 Dual/Quad Micropower, Single Supply Precision Op Amps SO-8 and 14-Lead Standard Pinout, 70µV VOS Max, 200kHz GBW 12 Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417 ● (408) 432-1900 FAX: (408) 434-0507 ● TELEX: 499-3977 ● www.linear-tech.com 1635f LT/TP 0997 4K • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 1997