PACVGA203
VGA Port Companion Circuit
Features
•
•
•
•
•
•
•
•
•
Single-chip solution for the VGA port interface
Includes ESD protection, level shifting, and RGB
termination
Seven channels of ESD protection for all VGA port
connector pins, meeting IEC-61000-4-2 Level-4
ESD requirements (8kV contact discharge)
Very low loading capacitance from ESD protection
diodes on VIDEO lines; 4pF typical
75Ω termination resistors for VIDEO lines
(matched to 1% typ.)
TTL to CMOS level-translating buffers with power-
down mode for HSYNC and VSYNC lines
Bi-directional level shifting N-channel FETs pro-
vided for DDC_CLK & DDC_DATA channels
Compact 24-pin QSOP package
Lead-free version available
Product Description
The PACVGA203 incorporates seven channels of ESD
protection for all signal lines commonly found in a VGA
port. ESD protection is implemented with current
steering diodes designed to safely handle the high
surge currents encountered with IEC-61000-4-2 Level-
4 ESD Protection (8kV contact discharge). When a
channel is subjected to an electrostatic discharge, the
ESD current pulse is diverted via the protection diodes
into either the positive supply rail or ground where it
may be safely dissipated. Separate positive supply
rails are provided for the VIDEO, DDC and SYNC
channels to facilitate interfacing with low voltage Video
Controller ICs and provide design flexibility in multi-
supply-voltage environments.
Two non-inverting drivers provide buffering for the
HSYNC and VSYNC signals from the Video Controller
IC (SYNC_IN1, SYNC_IN2). These buffers accept TTL
input levels and convert them to CMOS output levels
that swing between Ground and V
CC
4 (cont’d next
page).
Applications
•
•
Notebook computers with VGA port
Desktop PCs with VGA port
Simplified Electrical Schematic
V
CC
2
12
GNDD
VIDEO_1
VIDEO_2
VIDEO_3
3
4
5
GNDD
6
V
CC
2
GNDD
TERM_1
TERM_2
TERM_3
GNDA
8
9
10
7
GNDA
75
75
75
DDC_IN2
GNDD
17
R
C
18
DDC_OUT2
SYNC_IN2
GNDD
GNDD
GNDD
GNDD
21
24
SD2
V
CC
3
GNDD
R
C
V
CC
4
1
GNDD
22
R
S
SYNC_OUT2
GNDD
DDC_IN1
16
R
C
15
DDC_OUT1
R
B
GNDD
GNDD
11
SYNC_IN1
19
23
SD1
V
CC
1
2
V
CC
3
14
V_BIAS
13
D1
V
CC
4
1
20
R
S
SYNC_OUT1
GNDD
PWR_UP
©
2004 California Micro Devices Corp. All rights reserved.
12/07/04
430 N. McCarthy Blvd., Milpitas, CA 95035-5112
●
Tel: 408.263.3214
●
Fax: 408.263.7846
●
www.calmicro.com
1
CALMIRCO [ CALIFORNIA MICRO DEVICES CORP ]
