Airflow Airflow Sensors AWM3000 Series Microbridge Mass Airflow/Amplified Figure 1 Heater control circuit FEATURES 1 Laser trimmed for improved sensor interchangeability 1 Flow sensing up to 1.0 SLPM 1 Low differential pressure sensing Like the AWM2000 Series, the dual Wheatstone bridges control airflow mea- surement. The AWM3000 Series is ampli- fied therefore, it can be used to increase the gain and to introduce voltage offsets Figure 2 to the sensor output. The schematic in Sensing bridge supply circuit Figure 3 depicts the amplification circuitry on board the sensor. Also, the heater con- trol circuit (see Figure 1) and the sensing bridge supply circuit (see Figure 2) are on board the package. Figure 3 Differential instrumentation amplifier circuit Honeywell1 Sensing and Control 1 1-800-537-6945 USA1 F1-815-235-6847 International 1 1-800-737-3360 Canada 71Airflow Sensors AWM3000 Series Microbridge Mass Airflow/Amplified AWM3000 SERIES ORDER GUIDE (Performance Characteristics 10.01 0.01 VDC, 25C) Catalog Listings AWM3100V AWM3150V AWM3200V AWM3300V Flow Range (Full Scale) +200 sccm +30 sccm +1000 sccm Pressure Range (See Application Note 1) +2.0N H O (5 mBar) 2 Output Voltage Trim Point 5 VDC 200 sccm 3.4 VDC 25 sccm 5 VDC 2N H O 5 VDC 1000 sccm 2 Null Voltage 1.00 0.05 VDC 1.00 0.10 VDC 1.00 0.08 VDC 1.00 0.10 VDC Null Voltage Shift, Typ. +25 to -25C, 25 to +85C 25 mV 100 mV 25 mV 25 mV Output Voltage Shift, Max. +25 to -25C -4% Reading 5% Reading +24% Reading (Note 3) -5% Reading +25 to +85C +4% Reading 5% Reading -24% Reading +5% Reading Repeatability & Hysteresis, Max. 0.50% Reading 1% Reading 0.50% Reading 1% Reading Min. Typ. Max. Excitation VDC (Note 2) 8.0 100.01 15 Power Consumption (mW) 50 60 Response Time (msec) (Note 1) 1.0 3.0 Common Mode Pressure (psi) 25 Temperature Range Operating: -25 to +85C (-13 to +185F) Storage: -40 to +90C (-40 to +194F) Termination 2,54 mm (.100N) centers, 0,635 mm (0.025N) square Weight (grams) 10.8 Shock Rating 100 g peak (5 drops, 6 axes) Notes: 1. Initial warm-up time for signal conditioned circuitry is 1 minute max. 2. Output Voltage is ratiometric to supply voltage. 3. Temperature shifts when sensing differential pressure correlates to the density change of the gas over temperature. (See Application Note 1.) 4. Maximum allowable rate of flow change to prevent damage: 5 SLPM/1 sec. MOUNTING DIMENSIONS (for reference only) Note: Positive flow direction is defined as proceeding from Port 1 (P1) to Port 2 (P2) and results in positive output. Do not exert a force greater than 4.54kg (10 lbs.) in any direction. 72 Honeywell1 Sensing and Control 1 1-800-537-6945 USA1 F1-815-235-6847 International 1 1-800-737-3360 Canada
