
Preliminary Rev. 0.8 3/06
This information applies to a product under development. Its characteristics and specifications are subject to change without notice.
Copyright 2006 by Silicon Laboratories
Si8250/1/2
Si8250/1/2
D
IGITAL
P
OWER
C
ONTROLLER
Features
Description
Si8250/1/2 provides all control and protection functions necessary to implement
highly intelligent, fast response power delivery and management control systems
for isolated and non-isolated power supplies. On-board processing capability
enables intelligent control optimization for improved system performance and new
capabilities such as serial connectivity via the PMBus or on-board UART. The
Si8250/1/2 family is in-system Flash programmable enabling control and
protection parameters such as system regulation and protection settings, start-up
and shutdown modes, loop response, and modulation timing to be readily
modified. The built-in high-speed control path provides loop updates every 100nS
and provides pulse-by-pulse current limiting and over-current protection even
while the internal CPU is disabled.
The Si825x family is supported by the Si8250DK development kit, which contains
everything required to develop and program power supply applications with the
Si825x family of digital controllers.
Single-Chip, Flash-based digital
power controller
z
Supports isolated and non-isolated
applications
z
Enables new system capabilities
such as:
- Adaptive dead-time control for
higher efficiency
- Nonlinear control for faster
transient response
- Self diagnostics for higher
reliability
- Full PMBus command set
implementation for system
connectivity
Highly integrated control solution:
z
High-speed digital hardware
control loop
z
In-system programmable
supervisory processor
z
Programmable system protection
functions
z
Hardware cycle-by-cycle current
limiting and OCP
z
External clock and frame
synchronization inputs
z
Performs system management
functions such as external power
supply sequencing and fan
control/monitoring
In-system Flash programmable
z
Flash can also be used as NV
memory for data storage
Low cost, comprehensive
development tool kit includes:
z
Graphical, easy-to-use system
design tools
z
Integrated development
environment
z
In-system, on-line debugger
z
Turnkey isolated 35 W digital
half-bridge target board
Typical Applications
z
Isolated and non-isolated DC/DC
converters
z
AC/DC converters
Fully Pb-free and ROHS compliant
packages
z
32-pin LQFP
z
28-pin 5 x 5 mm QFN
Temp Range: –40 to +125 oC
Patents pending
Pin Assignments:
See page 23
4
5
6
7
2
1
3
1
1
1
1
9
8
1
18
17
16
15
20
21
19
2
2
2
2
2
2
2
Si8250/1/2
Top View
RST / C2CK
IPK
VSENSE
GND
VDD
VREF
P1.0/VIN/AIN0
P
P
P
P
P
P
P
P0.7
P0.6
P0.5
P0.4
P0.3/XCLK
P0.2
P0.1
P
P
P
P
P
P
P
GND
GND
1
VSENSE
P0.0
P0.5
P0.2
P0.1
P0.3 / XCLK
P1.0/VIN/AIN0
IPK
P0.6
P0.7
2
3
4
5
6
7
8
24
23
22
21
20
19
18
17
9
1
1
1
1
1
1
1
3
3
3
2
2
2
2
2
P0.4
Si8250/1/2
Top View
P1.1/AIN1
GNDA
VDDA
RST/C2CK
G
V
P
P
P
P
P
P
V
G
P
P
P
VREF
P
P
P
28-pin QFN
32-pin LQFP