Airflow Sensors Microbridge Mass Airflow/Unamplified and Amplified AWM40000 Series Figure 1 Heater Control Circuit FEATURES 1 Manifold mount/o-ring sealed 1 Ceramic flow-tube (non-outgassing), 0-1000 sccm 1 Plastic flow tube, 0-6 SLPM 1 High common mode pressure (150 psi ceramic flow-tube only) 1 Operating temperature up to 125C (unamplified only) 1 High stability at null and full-scale Figure 2 Sensing Bridge Supply Circuit The AWM40000 Series mass flow sensor family is based on proven microbridge technology and includes both amplified signal conditioned devices and unamplified sensor only devices. When using the unamplified devices (AWM42150VH and AWM42300V), the heater control circuit in Figure 1 and the sensing bridge supply circuit in Figure 2 are both required for operation per specification. These two circuits are NOT on board the sensor and must be supplied in the application. The differential amplifier circuitry in Figure 3 may be useful in providing output gain and/or introducing voltage offsets to the sensor output (Ref. Equation 1). Figure 3 Differential Instrumentation Amplifier Circuit The amplified devices (AWM43300V and AWM43600V) can be used to increase output gain and introduce voltage offsets. The differential instrumentation amplifier circuitry, heater control circuitry and sensing bridge supply circuitry are all provided onboard the amplified sensors. Equation 1: VoJ ( )( )( ) 2R2+R1 R1 where V offsetJVS 76 R4 R3 V2-V1 +V offset ( ) R6 R6+R5 Honeywell 1 Sensing and Control 1 1-800-537-6945 USA 1 F1-815-235-6847 International 1 1-800-737-3360 Canada Airflow Sensors Microbridge Mass Airflow/Unamplified and Amplified AWM40000 Series AWM40000 SERIES ORDER GUIDE (Performance Characteristics @ 10.01 0.01 VDC, 25C) Catalog Listings AWM42150VH AWM42300V AWM43300V AWM43600V Flow Range (Full Scale) 25 sccm 1000 sccm +1000 sccm +6 SLPM Output Voltage @ Trim Point 8.5 mV 1.5 mV @ 25 sccm 54.7 mV 3.7 mV DC @ 1000 sccm 5 V 0.15 VDC @ 1000 sccm 5 V 0.15 VDC @ 6 SLPM Null Voltage 0.0 1.0 mVDC 0.0 1.5 mVDC 1.0 0.05 VDC 1.0 0.05 VDC Null Voltage Shift +25 to -25C, +25 to +85C 0.20 mVDC 0.20 mVDC 0.025 VDC 0.025 VDC Output Voltage Shift +25 to -25C +25 to +85C +2.5% Reading typ. -2.5% Reading typ. +2.5% Reading max. -2.5% Reading max. -5.0% Reading max. +6.0% Reading max. -6.0% Reading max. +6.0% Reading max. Power Consumption (mW) 60 (Max.) 60 (Max.) 60 (Max.) 75 (Max.) Repeatability & Hysteresis 0.35% Reading (3) 0.50% Reading 0.50% Reading 1.00% Reading 8.00 (Typ.) Pressure Drop @ Full Scale (in H2O) 0.008N H2O (Typ.) 1.02 (Typ.) 1.02 (Typ.) Min. Typ. Max. Excitation VDC 8.0 100.01 15 Response Time (msec) -- 1.0 3.0 (Note 1) Common Mode Pressure (psi) (max.) -- -- 150 psi (10 Bar) Output Load Temperature Range 25 psi (1.7 Bar) NPN (Sinking): 10 mA PNP (Sourcing): 20 mA Operating: -40 to +125C (-40 to +251F) Storage: -40 to +125C (-40 to +251F) Calibration Gas Operating: -25 to +85C (-13 to +185F) Storage: -40 to +90C (-40 to +194F) Nitrogen Ratiometricity Error 0.30% Reading Weight (grams) 14 g Shock Rating 11 g 100 g peak (5 drops, 6 axes) Termination 2,54 mm (.100N) centers, 0,635 cm (0.025N) square Airflow Notes: 1. Response time is typically 1 msec from 10 to 90%. 2. Repeatability & Hysteresis tolerances reflect inherent inaccuracies of the measurement equipment. 3. Maximum allowable rate of flow change to prevent damage: 5.0 SLPM/1.0 sec. MOUNTING DIMENSIONS (for reference only) Amplified Sensors Unamplified Sensors Note: Positive flow direction is defined as proceeding from Port 1 (P1) to Port 2 (P2), and results in positive output. Honeywell 1 Sensing and Control 1 1-800-537-6945 USA 1 F1-815-235-6847 International 1 1-800-737-3360 Canada 77 Airflow Sensors Microbridge Mass Airflow/Unamplified and Amplified OUTPUT FLOW VS INTERCHANGEABILITY (Note 1) AWM40000 Series Performance Characteristics @ 10.0 0.01 VDC, 25C AWM42150VH AWM42300V AWM43300V AWM43600V Press Flow Nom. Tol. mBar sccm mV mV Press. Flow Nom. Tol. mBar sccm mV mV Press. Flow Nom. Tol. mBar sccm VDC VDC Press. Flow Nom. Tol. mBar SLPM VDC VDC 20 30 9.9 1.5 2.23 1000 54.7 2.00 2.23 1000 5.00 0.15 20.0 6 5.00 0.15 17 25 8.5 1.5 1.52 800 53.0 2.0 1.87 900 4.97 0.16 14.7 5 4.89 0.20 14 20 6.8 1.5 0.94 600 49.3 2.5 1.52 800 4.89 0.17 9.07 4 4.70 0.25 10 15 5.2 1.0 0.49 400 42.5 3.5 1.16 700 4.78 0.18 6.40 3 4.40 0.35 7 10 3.5 1.0 0.19 200 29.8 4.0 0.94 600 4.63 0.19 3.35 2 3.80 0.30 3 5 1.7 1.0 0.00 0 0.0 1.5 0.71 500 4.43 0.20 1.17 1 3.10 0.30 0 0 0.0 1.0 -0.19 -200 -29.8 4.0 0.50 400 4.15 0.21 0.00 0 1.00 0.05 -0.49 -400 -42.5 5.0 0.33 300 3.76 0.19 -0.94 -600 -49.3 6.0 0.19 200 3.23 0.17 -1.52 -800 -53.0 6.0 0.08 100 2.49 0.14 -2.23 -1000 -55.2 6.0 0.00 0 1.00 0.05 Notes: 1. Numbers in BOLD type indicate calibration type, mass flow or differential pressure. Tolerance values apply to calibration type only. 78 Honeywell 1 Sensing and Control 1 1-800-537-6945 USA 1 F1-815-235-6847 International 1 1-800-737-3360 Canada