STEVAL-ISA051V1 STMicroelectronics, STEVAL-ISA051V1 Datasheet - Page 34

• Manufacturer Part Number: STEVAL-ISA051V1
• Description: BOARD EVAL PM6670S DDR2/3
• Manufacturer: STMicroelectronics
• Type: DC/DC Switching Converters, Regulators & Controllersr

Specifications of STEVAL-ISA051V1

• Design Resources: STEVAL-ISA051V1 Gerber Files STEVAL-ISA051V1 Schematic STEVAL-ISA051V1 Bill of Material
• Main Purpose: Special Purpose DC/DC, DDR Memory Supply
• Outputs And Type: 4, Non-Isolated
• Voltage - Output: 1.5V, 1.8V
• Voltage - Input: 4.5 ~ 28V
• Regulator Topology: Buck
• Board Type: Fully Populated
• Utilized Ic / Part: PM6670
• Input Voltage: 4.5 V to 28 V
• Output Voltage: 1.8 V, 1.5 V
• Product: Power Management Modules
• Silicon Manufacturer: ST Micro
• Silicon Core Number: PM6670S
• Kit Application Type: Power Management
• Application Sub Type: DDR2/3 Memory Power Supply Controller
• Kit Contents: Board
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Current - Output: -
• Power - Output: -
• Frequency - Switching: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• For Use With/related Products: PM6670S
• Other names: 497-8411

Device description
7.1.8
34/54
VDDQ output discharge
Active discharge of VDDQ output occurs when PM6670S enters the suspend-to-disk system
state (S3 and S5 tied to GND) and DSCG pin has been properly set.
Figure 39. DSCG pin connection for discharge mode selection
The PM6670S allows the user to choose between fast discharge (tracking discharge), soft
discharge (non-tracking discharge) or no discharge modes. Voltage on DSCG multilevel pin
determines discharge mode as shown in
Table 9.
Tracking discharge allows the fastest discharge of all outputs but requires the LDOIN to be
self-supplied from VDDQ output voltage. When an external supply rail is connected to
LDOIN, it must be taken into account to avoid damage to the device. Discharge current (1 A)
flows through the LDOIN pin until the output has reached approximately 400 mV and then a
soft discharge completes the process by discharging the output with an internal 22 Ω switch.
Figure 40. Fast discharge and soft discharge options
1 V< VDSCG < 3.5 V
VDSCG > 4.2 V
VDSCG < 0.5 V
DSCG voltage
400mV
400mV
Discharge mode selection
VTT
VTT
VDDQ
VDDQ
V
V
REF
REF
Soft (non-tracking)
Soft-End type
Fast (tracking)
No discharge
Fast discharge
Fast discharge
+5V
+5V
Doc ID 14432 Rev 4
Soft discharge
Soft discharge
DSCG
DSCG
PM6670
PM6670
Table 9 on page 34
PM6670S
All outputs left floating.
VDDQ and VTT actively discharged by LDO trough
LDOIN and VTT pins;
All outputs discharged by dedicated internal MOS.
VTT
VTT
VDDQ
VDDQ
.
Description
Soft discharge
Soft discharge
PM6670S