Application hints

LPY550AL

8/12

Doc ID 15808 Rev 2

4

Application hints

Figure 3.

LPY550AL electrical connections and external components values

Power supply decoupling capacitors (100 nF ceramic or polyester + 10 µF Aluminum)

should be placed as near as possible to the device (common design practice).

The LPY550AL allows band limiting the output rate response through the use of an external

low pass filter (suggested) and/or high pass filter (optional) in addition to the embedded low

4xOUTX and 4xOUTZ are respectively OUTX and OUTZ amplified outputs lines, internally

buffered to ensure low output impedance.

If external high pass or low pass filtering is not applied it is mandatory to short-circuit

respectively pad 4 to pad 5 and pad 9 to pad 10 when amplified outputs are used.

When only not-amplified outputs are used (OUTX/Z), it is suggested to set pads 5 and 9 to

fixed reference voltage (Vref).

When high pass filter is applied to not amplified output (OUTx), it is recommended to buffer

the line before entering ADC for performance optimization.

The LPY550AL IC includes a PLL (phase locked loop) circuit to synchronize driving and

sensing interfaces. Capacitors and resistors must be added at FILTVDD and VCONT pins

(as shown in

Figure 3) to implement a low-pass filter.

100 nF

10kOhm

470nF

Vdd

GND

HP

Vref

C2

R1

C1

GND

10 µF

GND

Recomended

Low-pass filter

LPY550AL

(Top View)

1

16

14

13

9

8

6

5

10nF

PD

ST

GND

Optional

High-pass filter

Vref

GND

Typical values:

C1

R1

C2

R2

C1

R1

C2

R2

R1 = 1MOhm

C1 = 4.7 uF

R2 = 33kOhm

C2 = 2.2nF to 2.2uF

Not amplified

(TOP VIEW)

DIRECTION OF THE

DETECTABLE

ANGULAR RATES

+Ω

x

+Ω

z

filtered output X

Not amplified

filtered output Z