User Guide

NPM-5
CMT Module MA4 PAMS Technical Documentation
3DJH 1RNLD&RUSRUDWLRQ/WG ,VVXH
DUHSRZHUHGIURPDGHGLFDWHG9VXSSO\9&2%%$7KH&&217VXSSOLHVDOVR9IRU5)
&&217LQFOXGHVDOVRILYHDGGLWLRQDO9UHJXODWRUVSURYLGLQJSRZHUWRWKH5)VHFWLRQ
7KHVHUHJXODWRUVDUHFRQWUROOHGE\6:YLDWKHVHULDO%XV*(16,2IURPWKH
0$':'
&&217JHQHUDWHVDOVRD9UHIHUHQFHYROWDJH95()WR&2%%$7KH95()YROWDJHLVDOVR
XVHGDVDUHIHUHQFHWRVRPHRIWKH&&217$'FRQYHUWHUV
)LJXUH2XWSXWRYHUYROWDJHSURWHFWLRQZKHQWKHEDWWHU\LVUHPRYHG
Table 9: Regulator Activity - Different Operating Modes
2SHUDWLQJPRGH 9UHI 5)5(* 9&2%%$ 9&25( 9%% 96,0 6,0,)
3RZHURII 2II 2II 2II 2II 2II 2II 3XOOGRZQ
3RZHURQ 2Q 2Q2II 2Q 2Q 2Q 2Q 2Q2II
5HVHW 2Q 2II
952Q
952Q
2Q 2Q 2Q 2II 3XOOGRZQ
6OHHS 2Q 2Q2II 2II 2II 2Q 2Q 2Q2II
PWM
t
VOUT
t
4V
VLIM
"1"
"0"
SWITCH
t
ON
OFF
2
1.
1
Battery removed, (standard) charger connected, VOUT rises (follows charger
voltage)
2. VOUT exceeds limit VLIM(X), switch is turned immediately
OFF
3.
3
VOUT falls (because no battery) , also VCH<Vpor (standard chargers full-
rectified
output). When VCH > Vpor and VOUT < VLIM(X) -> switch turned on again (als
o
PWM
is still HIGH) and VOUT again exceeds
VLIM(X).
4
4. Software sets PWM = LOW -> CHAPS does not enter PWM
mode
Vstart
5
5. PWM low -> Startup mode, startup current flows until Vstart limit
reached
VCH
(Standard
Charger)
Vpor
Vstarthys
Droop depends on load
Istart off due to VCH<Vpor
& C in phone
6
6. VOUT exceeds limit Vstart, Istart is
turned off
7. VCH falls below
Vpor
7
Figure 11. Output overvoltage protection when battery removed ( in principle; not in
timescale