CS2001 Datasheet, PDF (1/8 Pages) ON Semiconductor – 1.2 A Switching Regulator, and 5.0 V, 100 mA Linear Regulator with RESET

CS2001
1.2 A Switching Regulator,
and 5.0 V, 100 mA Linear
Regulator with RESET
The CS2001 is a smart power supply ASIC utilized in automotive
airbag systems. It contains a current–mode switching regulator with a
1.2 A on–chip switch and a 5.0 V, 100 mA linear regulator. The linear
output capacitor must be 3.3 µF or greater with an ESR in the range of
100 mΩ to 1.0 Ω. If the ESR of the cap is less than 100 mΩ, a series
resistor must be used. The switcher can be configured in either a boost
or flyback topology. The boost topology produces energy reserve
voltage VER which is externally adjustable (25 V maximum) through
the resistor divider connected to the V_FB pin. In the event of fault
conditions that produce V_FB either open or shorted, the switcher is
shut down.
Under normal operating conditions (V_BAT > 8.0 V), the current
loading on the linear regulator is directed through V_BAT. A low battery
or loss of battery condition switches the supply for the linear regulator
from V_BAT to VER and shuts down the switcher using the ASIC’s
internal “smartswitch.” This switchover feature minimizes the power
dissipation in both the linear and switcher output devices and saves the
cost of using a larger inductor.
The NERD (No Energy Reserve Detected) pin is a dual function
output. If V_OUT is not in regulation, it provides a Power On Reset
function whose time interval is externally adjustable with the
capacitor. This interval can be seen on the RESETB pin, which allows
for clean power–up and power–down of the microprocessor. Once
V_OUT is in regulation, the logic level of the NERD output (usually
low) indicates to the microprocessor whether or not the VER pin is
connected.
A switched–capacitor voltage tripler accepts input voltage VER and
produces output voltage V_CHG (typically VER + 8.0 V). This voltage
is used in the system to drive high–side FETs.
This part is capable of withstanding a 50 V peak transient voltage.
The linear regulator will not shut down during this event.
Features
• Linear Regulator 5.0 V ±2% @ 100 mA
• Switching Regulator 1.2 A Peak Internal Switch
• Voltage Tripler
• Smart Functions
– Smartswitch
– RESET
– Energy Reserve Status
• Protection
– Overtemperature
– Current Limit
– 50 V Peak Transient Capability
• Internally Fused Leads in SO–20L Package
http://onsemi.com
20
1
SO–20L
DWF SUFFIX
CASE 751D
MARKING DIAGRAM
20
CS2001
AWLYYWW
1
A
= Assembly Location
WL, L = Wafer Lot
YY, Y = Year
WW, W = Work Week
PIN CONNECTIONS
1
VER
V_BAT
V_FB
GND1
GND2
GND3
GND4
V_SW
SWSD
COMP
20
V_OUT
RESETB
NERD
GND8
GND7
GND6
GND5
V_CHG
I_BIAS
C_PUMP
ORDERING INFORMATION
Device
Package
Shipping
CS2001YDWF20 SO–20L 37 Units/Rail
CS2001YDWFR20 SO–20L 1000 Tape & Reel
© Semiconductor Components Industries, LLC, 2001
1
December, 2000 – Rev. 5
Publication Order Number:
CS2001/D