Device description
PM6670S
7.1.8
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
+5V
PPMM66667700S
VREF
DSCG
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 on page 34.
Table 9. Discharge mode selection
DSCG voltage
Soft-End type
Description
VDSCG > 4.2 V
No discharge All outputs left floating.
1 V< VDSCG < 3.5 V
VDSCG < 0.5 V
Fast (tracking)
Soft (non-tracking)
VDDQ and VTT actively discharged by LDO trough
LDOIN and VTT pins;
All outputs discharged by dedicated internal MOS.
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
VDDQ
VTT
400mV
Fast discharge
Soft discharge
VDDQ
VTT
Soft discharge
34/54
Doc ID 14432 Rev 4