AD8370

Rev. A | Page 23 of 28

Figure 60. Evaluation Software

Table 7. AD8370 Evaluation Board Configuration Options

Component

Function

Default Condition

VS, GND, VOCM

Power Interface Vector Pins. Apply supply voltage between VS and GND. The VOCM

pin allows external monitoring of the common-mode input and output bias levels.

Not applicable

SW1, R8,

C10, PWUP

Device Enable. Set to Position B to power up the device. When in Position A, the PWUP

pin is connected to the PWUP vector pin. The PWUP pin allows external power cycling

of the device. R8 and C10 are provided to allow for proper cable termination.

SW1 = installed

R8 = 49.9 Ω (Size 0805)

C10 = open (Size 0805)

P1, R5, R6,

R7, C9

Serial Control Interfaces. The evaluation board can be controlled using most PCs.

Windows®-based control software is shipped with the evaluation kit. A 25-pin, D-sub

connector cable is required to connect the PC to the evaluation board. It may be

necessary to use a capacitor on the clock line, depending on the quality of the PC port

signals. A 1 nF capacitor for C9 is usually sufficient for reducing clock overshoot.

P1 = installed

R5, R6, R7 = 1 kΩ (Size 0603)

C9 = open (Size 0603)

J1, J2, J6, J7

Input and Output Signal Connectors. These SMA connectors provide a convenient way

to interface the evaluation board with 50 Ω test equipment. Typically, the device is

evaluated using a single-ended source and load. The source should connect to

J1 (IN+), and the load should connect to J6 (OUT+).

Not applicable

C1, C2, C3, C4

AC Coupling Capacitors. Provide ac coupling of the input and output signals.

C1, C2, C3, C4 = 1 nF (Size 0603)

T1, T2

Impedance Transformers. T1 provides a 50 Ω to 200 Ω impedance transformation.

T2 provides a 100 Ω to 50 Ω impedance transformation.

T1 = TC4 −1W (Mini-Circuits)

T2 = JTX−2−10T (Mini-Circuits)

R1, R2, R3, R4

Single-Ended or Differential. R2 and R4 are used to ground the center tap of the

secondary windings on transformers T1 and T2. R1 and R3 should be used to ground

J2 and J7 when used in single-ended applications.

R1, R2, R3, R4 = 0 Ω (Size 0603)

C5, C6, C7,

C8 L1, L2

Power Supply Decoupling. Nominal supply decoupling consists of a ferrite bead

series inductor followed by a 1 μF capacitor to ground followed by a 0.1 μF capacitor

to ground positioned as close to the device as possible. C7 provides additional

decoupling of the input common-mode voltage. L1 provides high frequency

isolation between the input and output power supply. L2 provides high

frequency isolation between the analog and digital ground.

C6 = 1 μF (Size 0805)

C5, C7, C8 = 0.1 μF (Size 0603)

L1, L2 = HZ1206E601R-00

(Steward, Size 1206)