Texas Instruments LM2907MX/NOPB Product Information

Product Overview

The LM2907MX/NOPB is a frequency-to-voltage converter from Texas Instruments, designed for applications requiring accurate and stable frequency-to-voltage conversion. It features a high gain op amp and a tachometer input with built-in hysteresis, making it suitable for a wide range of applications, including speedometers, tachometers, and frequency-to-voltage conversion.

Detailed Specifications

Basic Information

• Series: LM2907
• Package Type: SOIC (14-pin)
• Body Size (Nom): 3.91 mm × 8.65 mm
• Operating Temperature Range: -40°C to +85°C
• Supply Voltage Range: 2V to 28V
• Output Current Capability: 50 mA (sink or source)

Features

• Ground Referenced Tachometer Input: Interfaces directly with variable reluctance magnetic pickups.
• Floating Transistor Output: Allows for ground or supply-referred loads.
• Frequency Doubling: For low-ripple operation.
• Built-in Hysteresis: For noise rejection and stable operation.
• Zener Regulator: Ensures accurate and stable frequency-to-voltage conversion.
• Output Swings to Ground: For zero frequency input.
• Easy to Use: Output voltage formula: VOUT​=fIN​×VCC​×R1×C1.

Applications

• Over and Under-Speed Sensing
• Frequency-to-Voltage Conversion (Tachometer)
• Speedometers
• Breaker Point Dwell Meters
• Hand-Held Tachometers
• Speed Governors
• Cruise Control
• Automotive Door Lock Control
• Clutch Control
• Horn Control
• Touch or Sound Switches

Pin Configuration and Functions

• COL (Pin 8): Collector of the bipolar junction transistor.
• CP1 (Pin 2): Capacitor charging pin.
• CP2 (Pin 3): Capacitor discharging pin.
• EMIT (Pin 5): Emitter of the bipolar junction transistor.
• GND (Pin 12): Ground.
• IN+ (Pin 4): Non-inverting input to the high gain op amp.
• IN- (Pin 10): Inverting input to the high gain op amp.
• TACH+ (Pin 1): Positive terminal for the input signal.
• TACH- (Pin 11): Negative terminal for the input signal.
• V+ (Pin 9): Supply voltage.

Electrical Characteristics

• Input Threshold Voltage: ±10 mV to ±40 mV (typical ±25 mV).
• Hysteresis: 30 mV.
• Offset Voltage: ±15 mV (typical).
• Input Bias Current: 0.1 μA to 1 μA.
• High Level Output Voltage: 8.3 V (typical).
• Low Level Output Voltage: 2.3 V (typical).
• Output Current: 140 μA to 240 μA (typical 180 μA).
• Leakage Current: 0.1 μA (typical).
• Gain Constant: 0.9 to 1.1 (typical 1).
• Linearity: ±0.3% (typical).

Mechanical and Packaging

• Package Type: SOIC (14-pin)
• Body Size (Nom): 3.91 mm × 8.65 mm
• Lead Finish: Green (RoHS & no Sb/Br)
• Moisture Sensitivity Level (MSL): Level-1-260C-UNLIM
• Peak Solder Temperature: 260°C

Ordering Information

• Part Number: LM2907MX/NOPB
• Package Option: SOIC (14-pin)
• Lead/Ball Finish: Green (RoHS & no Sb/Br)
• Moisture Sensitivity Level (MSL): Level-1-260C-UNLIM
• Peak Solder Temperature: 260°C
• Operating Temperature Range: -40°C to +85°C
• Device Marking: LM2907MX