8-Bit, Programmable, 2- to 3-Phase,
Synchronous Buck Controller
ADP3193A
FEATURES
FUNCTIONAL BLOCK DIAGRAM
VCC
RT RAMPADJ
Selectable 2- or 3-phase operation at up to 1 MHz per phase
7.7 mV worst-case differential sensing error over
temperature
23
9
10
SHUNT
REGULATOR
OSCILLATOR
15
22
21
20
OD
UVLO
Logic-level PWM outputs for interface to external high
power drivers
Fast enhanced PWM (FEPWM) flex mode for excellent load
transient performance
Active current balancing between all output phases
Built-in power-good/crowbar blanking supports on-the-fly
VID code changes
Digitally programmable 0.5 V to 1.6 V output supports both
VR10.x and VR11 specifications
SHUTDOWN
SET EN
RESET
+
14
1
GND
EN
CMP
PWM1
PWM2
PWM3
–
–
+
850mV
+
CMP
RESET
DAC
+150mV
–
–
+
2-/3-PHASE
DRIVER LOGIC
CSREF
+
–
+
RESET
CMP
–
DAC
–350mV
CURRENT
LIMIT
DELAY
2
CROWBAR
PWRGD
Programmable short-circuit protection with programmable
latch-off delay
19
18
SW1
SW2
17 SW3
13
11
CSCOMP
CSREF
APPLICATIONS
8
7
ILIMIT
CURRENT
+
–
MEASUREMENT
AND LIMIT
Desktop PC power supplies for
Next generation Intel® processors
VRM modules
DELAY
12
4
CSSUM
16
5
IREF
–
+
FB
COMP
GENERAL DESCRIPTION
–
PRECISION
REFERENCE
+
The ADP3193A1 is a highly efficient, multiphase, synchronous
buck switching regulator controller optimized for converting a
12 V main supply into the core supply voltage required by high
performance Intel processors. It uses an internal 8-bit DAC to read
a voltage identification (VID) code directly from the processor,
which is used to set the output voltage between 0.5 V and 1.6 V.
BOOT
3
FBRTN
VIDSEL
VOLTAGE
AND
6
SS
SOFT START
CONTROL
VC DAC
32
ADP3193A
24
25
26
27
28
29
30
31
VID7 VID6 VID5 VID4 VID3 VID2 VID1 VID0
Figure 1.
This device uses a multimode PWM architecture to drive the
logic-level outputs at a programmable switching frequency that
can be optimized for VR size and efficiency. The phase relation-
ship of the output signals can be programmed to provide 2- or
3-phase operation, allowing for the construction of up to three
complementary buck switching stages.
The ADP3193A has a built-in shunt regulator that allows the
part to be connected to the 12 V system supply through a series
resistor.
The ADP3193A is specified over the extended commercial
temperature range of 0°C to 85°C and is available in a
32-lead LFCSP.
The ADP3193A also includes programmable no load offset and
slope functions to adjust the output voltage as a function of the
load current, optimally positioning it for a system transient. The
ADP3193A also provides accurate and reliable short-circuit
protection, adjustable current limiting, and delayed power-good
output that accommodates on-the-fly output voltage changes
requested by the CPU.
1 Protected by U.S. Patent Number 6,683,441; other patents pending.
©2008 SCILLC. All rights reserved.
February 2008 – Rev. 1
Publication Order Number:
ADP3193A/D