ADVANCED LINEAR ALD2321A/ALD2321B/ALD2321 DEVICES, INC. ULTRA LOW VOS EPAD DUAL CMOS ANALOG VOLTAGE COMPARATOR GENERAL DESCRIPTION FEATURES Ultra low signal power of 4fW detectable The ALD2321A/ALD2321B/ALD2321 is a monolithic Precision Dual Volt- Ultra low offset voltage of max. 0.2mV age Comparator, each having integrated dual complementary output Ultra low input bias currents of typ. 0.01pA drivers. It is constructed using advanced silicon gate CMOS technology. Low supply current of 110A typical Key features of the ALD2321A/ALD2321B/ALD2321 include very high Virtually eliminates source impedance effects input impedance, very low offset voltage utilizing on-chip e-trim (EPAD Low operating supply voltage of 4V to 10V electronic-trimming) technology, flexible multiple output configurations and Single (+5V) and dual supply (5V) operation fast response time with small overdrive voltage. It is designed for ultra low High speed for both small and large level level signal detection from high impedance sources. For many applications signals 300ns typical for TTL inputs the ALD2321A/ALD2321B/ALD2321 can eliminate an input amplification CMOS, NMOS and TTL compatible stage, a precision input bias stage, a signal level shift stage and an output Each comparator has separate push and buffer stage, and do the entire job from low level input signal detection to high pull outputs output driver -- all on a single chip. High output sink current - typically 50mA Low supply current spikes Fanout of 30 TTL loads The input voltage includes ground, making this voltage comparator ideal for single supply (+5V) or dual supply ( 5V) powered systems. For dual supply applications, GND pin is connected to the most negative supply instead of APPLICATIONS Ground (0.0V). The negative supply voltage can be at any value between 0.0V and -5V. Each voltage comparator is individually trimmed at the factory Dual limit window comparator for minimum offset voltage at ground voltage potential, making the ALD2321A/ Power supply voltage monitor ALD2321B/ALD2321 at its best offset voltage and ready to compare very Photo-detector sensor circuit Relay or LED driver low signal level voltages at or near ground potential. Typically a signal less Oscillators than 1mV can be resolved and detected reliably without requiring amplifica- Battery operated instruments tion. Sensor or detector signals with signal power as low as 0.004pW (4 x -15 Remote signal detection 10 Watt) can be readily detected. Each voltage comparator has two complementary output pins, one for Source Output (OUT ) and the other for Sink Output (OUT). This dual H complementary output allows maximum circuit design flexibility. The out- PIN CONFIGURATION puts can be used as Single-Ended Driver, Multiple WIRED-OR Outputs, Push-Pull Outputs or Complementary Outputs. The Sink Output can be used as an open drain output, which has current sink capability of up to 50mA. It can also be connected to an external voltage higher or lower than + OUT 1 16 V 1 V+, which provide level shift of the output swing levels from other than V+ to GND. The Source Output can source up to 2mA and can be used to drive OUT 2 15 OUT 2 1H the base terminal of an external NPN bipolar device or the gate of a N- 3 14 OUT -IN 1 2H channel MOSFET device. Alternatively, the two outputs, Source Output and -IN +IN 4 13 2 1 ORDERING INFORMATION (L suffix for lead free version) GND 5 12 +IN 2 Operating Temperature Range * 6 11 VE VE 11 21 0C to +70C0C to +70C -55C to +125C VE 7 10 VE 12 22 16-Pin 16-Pin 16-Pin * * Small Outline Plastic Dip CERDIP 8 9 N/C N/C Package (SOIC) Package Package SCL, PCL, DC PACKAGES ALD2321ASCL ALD2321APCL ALD2321ADC ALD2321BSCL ALD2321BPCL ALD2321BDC *N/C pins are connected internally. ALD2321SCL ALD2321PCL ALD2321DC Do not connect externally. * Contact factory for leaded (non-RoHS) or high temperature versions. Rev 2.0 2010 Advanced Linear Devices, Inc. 415 Tasman Drive, Sunnyvale, CA 94089-1706 Tel: (408) 747-1155 Fax: (408) 747-1286 www.aldinc.comGENERAL DESCRIPTION (cont d) Sink Output, can be connected together to form a push-pull output In a printed circuit board layout, it is suggested that which has the combined output capabilities of both channels. these pins, along with no connect (N/C) pins 8 and 9, be surrounded with ground traces to prevent any In the dual complementary output mode, each comparator can be possible crosstalk and noise coupling from other signal used to drive separate loads. Due to the complementary nature of sources. the two outputs, only one output is active at any a given time, except for a limited crossover time. When OUT (sink output) is active ON, Although not required for most applications, if neces- the OUT pin is sinking current and the OUT pin is OFF and in high sary, small valued capacitors of approximately 1000pF H impedance mode. Conversely, if OUT pin is ON and sourcing can be mounted at these pins to ground to further H current, OUT pin is OFF. To configure push-pull output, simply reduce noise. For information on customized trimming connect OUT (sink output) pin to OUT pin. under different biasing and power supply conditions, H please contact factory. Since each voltage comparator has its own complementary out- puts, each comparator can be configured to have a different output type. For example, one comparator output can be connected as BLOCK DIAGRAM Open Drain output while the other comparator can be wired as push-pull output. If used to drive capacitive loads, the output DC + current levels are at a very low level, at essentially leakage current (16) V levels, which can be a power saving feature. INVERTING INPUT - (2) OUT 1H -IN (3) The ALD2321A/ALD2321B/ALD2321 can detect and resolve very 1 (1) OUT 1 low voltage levels at high speed, with little or no overdrive voltage. NONINVERTING INPUT + Compared with other voltage comparator devices that require 100 +IN (4) 1 (7) VE 12 mV overdrive voltages, or multiple stage circuits that include input (6) VE 11 preamp, etc., the ALD2321A/ALD2321B/ALD2321 can perform all (5) GND input to output functions in one device with minimal delay time and with as low as a 1mV signal. The ALD2321A/ALD2321B/ALD2321 is supplied with 4 external e- INVERTING INPUT - (14) OUT 2H trim pins, VE11, VE12, VE21, and VE22. These pins are used for -IN (13) 2 (15) OUT 2 trimming of the voltage comparator offset voltages at the factory, NONINVERTING INPUT + and normally should be left open unconnected. However, in some +IN (12) 2 (10) VE 22 cases these pins can be used as positive/negative feedback pins, (11) VE 21 since these pins have a positive/negative factor on the offset voltage. For example, see TYPICAL APPLICATIONS section (8) (9) titledVoltage Comparator With Output Feedback to Provide N/C N/C Hysteresis ALD2321 PIN IDENTIFICATION PIN SYMBOL FUNCTION SIGNAL PROPAGATION 1 OUT COMPARATOR 1 SINK OUTPUT OUTPUT 1 2 OUT COMPARATOR 1 SOURCE OUTPUT OUTPUT 1H 3 -IN COMPARATOR 1 INVERTING INPUT INPUT 1 4 +IN COMPARATOR 1 NON-INVERTING INPUT INPUT 1 5 GND GROUND / V- SUPPLY - 6VE - VOS E-Trim COMPARATOR 1 INPUT 11 7VE + VOS E-Trim COMPARATOR 1 INPUT 12 8 N/C No Connect/Do Not connect externally - 9 N/C No Connect/Do Not connect externally - 10 VE +VOS E-Trim COMPARATOR 2 INPUT 22 11 VE - VOS E-Trim COMPARATOR 2 INPUT 21 12 +IN COMPARATOR 2 NON-INVERTING INPUT INPUT 2 13 -IN COMPARATOR 2 INVERTING INPUT INPUT 2 14 OUT COMPARATOR 2 SOURCE OUTPUT OUTPUT 2H 15 OUT COMPARATOR 2 SINK OUTPUT OUTPUT 2 16 V+ V+ SUPPLY - ALD2321A/ALD2321B/ALD2321 Advanced Linear Devices 2 of 11