ISZ-500 INVENSENSE, ISZ-500 Datasheet - Page 12

• Manufacturer Part Number: ISZ-500
• Description: GYRO, SINGLE (Z) AXIS, +/-500 DEG/S
• Manufacturer: INVENSENSE

Specifications of ISZ-500

• No. Of Axes: 1
• Sensor Case Style: QFN
• No. Of Pins: 28
• Supply Voltage Range: 2.7V To 3.3V
• Operating Temperature Range: -20°C To +85°C
• Sensitivity Per Axis: 2mV / ° / S
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

8.2
CONFIDENTIAL & PROPRIETARY
8.2.1
The gyro is most susceptible to power supply noise (ripple) at frequencies less than 100Hz. At less
than 100Hz, the PSRR is determined by the overall internal gain of the gyroscope. Above 100Hz, the
PSRR is determined by the characteristics of the on-chip low-pass filter. Above 1kHz, the PSRR is
relatively constant except for a narrow frequency range corresponding to the resonant frequency of the
Z-gyroscope.
8.2.2
The Power Supply Voltage (VDD) rise time (10% - 90%) must be less than 20ms at VDD (Pins 9 and
19) for proper device operation.
The ISZ-500 gyroscope should be isolated from system power supply noise by a combination of an RC
filter that attenuates high frequency noise and a Low Drop Out linear regulator (LDO) that attenuates
low frequency noise. Figure 4 shows a typical configuration.
The low-pass RC filter should be chosen such that it provides significant attenuation of system noise at
high frequencies. The LDO should be a low noise regulator (<100V/rtHz) that exhibits good noise
rejection at low frequencies.
8.2.3
The scale factor of the gyroscope depends on the amplitude of the mechanical motion and the trim
setting of the internal programmable gain stages.
amplitude to maintain constant sensitivity over the specified temperature range. The capacitor
connected to Pin 15 (ZAGC) is a compensation capacitor for the amplitude control loop.
8.2.4
A built-in Proportional-To-Absolute-Temperature (PTAT) sensor provides temperature information on
Pin 23 (PTATS). The temperature sensor output signal is analog, and has a bias of approximately
1.25V at room temperature, and increases at a rate of 4mV/ºC. The output impedance is nominally
12kΩ and is therefore not designed to drive low impedance loads. If necessary, the output can be
externally buffered with a low offset-drift buffer, and optionally a low-pass filter to minimize noise.
8.2.5
After the demodulation stage, there is a low-pass filter. This filter limits noise and high frequency
artifacts from the demodulator before final amplification. The following graph shows the typical gain
and phase response. The low-pass filter has been designed for a nominally flat gain up to the cutoff
frequency while still achieving a low phase delay at 10Hz and 30Hz.
Design Considerations
Power Supply Rejection Ratio
Power Supply Filtering
Amplitude Control
Temperature Sensor
Internal Low-Pass Filter
ISZ-500 Single-Axis Z-Gyroscope
Product Specification
12 of 24
Figure 4
The oscillation circuit precisely controls the
PS-ISZ-0500B-00-03
Release Date: 07/08/09