Si57x-EVB

Rev. 0.2

3

1. Functional Description

VCO. This evaluation board assembly provides access to all signals for programming and operating the device.

The Si57x-EVB assembly motherboard and daughterboard schematics, bills of material, and PCB layouts are

appended as sections 5, 6 and 7, respectively. Reference designators below refer to the Si57x-EVB motherboard

unless otherwise noted. The Si57x-EVB is oriented with the daughterboard at the bottom in the directions below.

1.1. Motherboard-Daughterboard Connection

The Si57x-EVB motherboard connects to the Si57x daughterboard at connectors J13-J14. Each of these is a 2x20

pin, impedance controlled connector. The connectors are keyed so there is only one proper way to install the

board. Orient the boards on installation so that the silkscreen triangle on the daughterboard matches the silkscreen

on the motherboard.

1.2. Power Supply

The Si57x-EVB is pre-configured to accept 5 V from the USB connector at J15. To change the board's 5 V power

supply from the USB connection to the terminal block at J18, make these changes:



Remove R7.



Populate R8.

Note: If both R7 and R8 are installed, do not simultaneously connect to both the USB connector at J15 and to a separate 5 V

supply at J18. Otherwise, power supply contention may occur.

Typical supply current draw for the Si57x-EVB assembly (motherboard + daughterboard) is approximately 230 mA.

See the device data sheet for device power consumption specifications.

The evaluation daughter board are designed to operate at any of the following nominal voltages: 1.8, 2.5, or 3.3 V.

The Si57x-EVB has an on-board voltage regulator which supplies any of these voltages. The Si57x-EVB voltage

regulator is controlled via jumpers. By default, a jumper is installed, selecting 3.3 V for the Si57x/598/599.

Alternatively, VREG may be set to 1.8 or 2.5 V per Table 1.

Table 1. VREG Jumpers

Voltage

Selection

J6 Jumper Installation

(Assuming S/W Control Unavailable)

3.3

Connect pin 1 “3.3 V” to center pin 2

2.5

Connect pin 3 “2.5 V” to center pin 2

1.8

No jumper